The Impact of Privatized Education on the Level of Labour Productivity

Jaewon Kim - Statistics for International Relations Research II

1. Introduction

The aim of this research is to explore the potential causal relationship between the privatization of education and labor productivity.In recent years, many countries have embarked on the application of market-based privatization approaches to different levels of education. Mounting budget deficits of the government, deteriorating quality of services, and out-of-date curriculum are among the core reasons why a huge portion of responsibilities to education service delivery that have long been recognized as public goods were shifted onto the private sector. The theoretical rationale behind the privatization of education is that market-oriented forces can better serve as a tool to increase the quality of the education while lowering the cost through extensive competition among providers, ensure more flexibility in contracting of competent teacher, and above all, to reduce the burden of education cost and expectations (Fennell, 2012; Steiner-Khamsi & Draxler, 2018).

However such trend has also stimulated considerable controversy as the private sector is inherently ‘profit-seeking’ and ‘efficiency-seeking.’ Many scholars and practitioners point out that such different nature of the private sector would rather hamper the universal access to education or damage the quality of education in a long run. Compared to sectors such as transportation, roads, or energy that have widely enjoyed the engagement of the private sector, the education sector, therefore, is relatively a late adopter of privatization schemes, due in large part to the widely-held perception that the provision and management of education services ought to be the responsibility of the public sector as it is a public good (Draxler, 2013).

Against this backdrop, this research attempts to examine whether the privatization of education contributes to the improvement of labour productivity. Among different levels of education from pre-primary to tertiary, this research will specifically focus on secondary education due to the fact that it is generally considered to play a fundamental role in preparing pupils directly for the labour market as it is when the pupils start receiving ‘vocational education’. This study will examine whether there is any meaningful causal relationship between the level of the private sector engagement in education and labour productivity by testing the hypothesis ‘The increased level of private sector engagement in the delivery of secondary education services increases overall labour productivity.’

2. Data

To test the hypothesis, the first model will use a ‘School enrollment, secondary, private (% of total secondary)’ data set prepared by the World Bank as the independent variable. It shows the ratio of pupils enrolled in institutions that are operated by a private sector body, not a public authority, from 1998 to 2019.A high ratio would consequently mean that the private sector (e.g. NGOs, firms, religious bodies, or local communities)is strongly engaged in the delivery of education services. An ‘output per worker (GDP constant 2011 international $ in PPP)’ data set prepared by ILO will be the dependent variable. Labour productivity in this data set refers to the total volume of output (GDP) produced per one-unit of labour during a time frame of 2010-2019. The usage of this data set is expected to allow me to assess the level of GDP-to-labour input as well as growth rates over the given time frame, which would help me identify the degree of efficiency as well as quality of labour in the production process in each sample country.

lpdata <- read.csv("ILO_labour_productivity.csv",  header = TRUE)

pedata <- read.csv("WB_private education.csv",  header = TRUE)

Both are time series data sets that contain a total of 3 variables - country, year, and value. However we can see that there is difference in the number of observations as the number of countries covered are different: labour productivity data has 1890 observations of a total of 189 countries while private education data has 1780 observations of a total of 178 countries. Some countries covered in the private education data are missing in the labour productivity data, and vice versa. For example, the private education data developed by the World Bank contains a number of territories that are not recognized as a country under the UN system, such as Gibraltar, a British overseas territory and headland or West Bank and Gaza area. However it only includes countries who have data for at least one year during the given time span. Therefore I will tailor the extra variables of the World Bank data and ILO data to combine two data frames vertically in the later stage.

Three control variables that are assumed to be related (either closely or loosely) to labour productivity will be also added: mean weekly working hour (mwwhour), consumer price for health service (healthconpri), and average cost for educational services (educost). All three data sets are those imported from ILO. A data set of ‘weekly working hour’ presents the mean values of weekly working hours of all employees, while the remaining two data sets of consumer price for health service and average cost for educational services present the values of consumer price index (CPI).

working_hr <- read.csv("mean_weekly_working_hour.csv",  header = TRUE)

conpri_health <- read.csv("consumer_price_health.csv",  header = TRUE)

edu_price <- read.csv("education_service_aveprice.csv",  header = TRUE)

All three of them have 3 variables: country, year, value, and they all cover maximum 10 years of data between 2010 and 2019. However, the volume of observations vary (2079 for mwwhour; 1717 for healthconpri; and 1676 for educost) according to the availability of country data.

3. Visualization of the distribution of the variable

(1-1) The distribution of the dependent variable by year

library(arsenal)
require(knitr)

## Loading required package: knitr

require(survival)

## Loading required package: survival

str(lpdata)

## 'data.frame':    1890 obs. of  3 variables:
##  $ Country: chr  "Afghanistan" "Afghanistan" "Afghanistan" "Afghanistan" ...
##  $ Year   : int  2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 ...
##  $ Value  : int  9573 9219 9910 9943 9697 9365 9178 9048 8871 8794 ...

lpdata_table <- tableby(Year ~ Value, data = lpdata) 
summary(lpdata_table, title = "Labour Productivity Data - Summary Statistics, by year")

## 
## 
## Table: Labour Productivity Data - Summary Statistics, by year
## 
## |                            |     2010 (N=189)      |     2011 (N=189)      |     2012 (N=189)      |     2013 (N=189)      |     2014 (N=189)      |     2015 (N=189)      |     2016 (N=189)      |     2017 (N=189)      |     2018 (N=189)      |     2019 (N=189)      |    Total (N=1890)     | p value|
## |:---------------------------|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|-------:|
## |**Value**                   |                       |                       |                       |                       |                       |                       |                       |                       |                       |                       |                       |   1.000|
## |&nbsp;&nbsp;&nbsp;Mean (SD) | 44040.635 (41188.903) | 44590.513 (42246.687) | 44929.180 (42127.220) | 45270.444 (42554.979) | 45461.772 (42289.946) | 45506.132 (41560.604) | 45841.190 (41852.116) | 46372.979 (42421.424) | 46816.640 (42865.544) | 47013.016 (42849.813) | 45584.250 (42107.871) |        |
## |&nbsp;&nbsp;&nbsp;Range     | 1534.000 - 240632.000 | 1535.000 - 242518.000 | 1510.000 - 245190.000 | 1492.000 - 265200.000 | 1478.000 - 253445.000 | 1480.000 - 240693.000 | 1472.000 - 249868.000 | 1441.000 - 244315.000 | 1430.000 - 244196.000 | 1419.000 - 241729.000 | 1419.000 - 265200.000 |        |

(1-2) The distribution of the dependent variable by country

lpdata_table_2 <- tableby(Country ~ Value, data = lpdata) 
summary(lpdata_table_2, title = "Labour Productivity Data - Summary Statistics, by country")

## 
## 
## Table: Labour Productivity Data - Summary Statistics, by country
## 
## |                            | Afghanistan (N=10)  |    Albania (N=10)     |    Algeria (N=10)     |     Angola (N=10)     |   Argentina (N=10)    |    Armenia (N=10)     |   Australia (N=10)    |     Austria (N=10)      |   Azerbaijan (N=10)   |    Bahamas (N=10)     |    Bahrain (N=10)     |  Bangladesh (N=10)   |    Barbados (N=10)    |    Belarus (N=10)     |     Belgium (N=10)      |     Belize (N=10)     |    Benin (N=10)     |     Bhutan (N=10)     |    Bolivia (N=10)     | Bosnia and Herzegovina (N=10) |    Botswana (N=10)    |     Brazil (N=10)     | Brunei Darussalam (N=10) |    Bulgaria (N=10)    | Burkina Faso (N=10) |   Burundi (N=10)    | C?te d'Ivoire (N=10)  |   Cambodia (N=10)   |   Cameroon (N=10)   |     Canada (N=10)     |   Cape Verde (N=10)   | Central African Republic (N=10) |     Chad (N=10)     | Channel Islands (N=10) |     Chile (N=10)      |     China (N=10)      |    Colombia (N=10)    |    Comoros (N=10)     |     Congo (N=10)     | Congo, Democratic Republic of the (N=10) |   Costa Rica (N=10)   |    Croatia (N=10)     |      Cuba (N=10)      |     Cyprus (N=10)     |    Czechia (N=10)     |     Denmark (N=10)      |   Djibouti (N=10)    | Dominican Republic (N=10) |    Ecuador (N=10)     |     Egypt (N=10)      |  El Salvador (N=10)   | Equatorial Guinea (N=10) |   Eritrea (N=10)    |    Estonia (N=10)     |    Eswatini (N=10)    |   Ethiopia (N=10)   |      Fiji (N=10)      |     Finland (N=10)     |      France (N=10)      | French Polynesia (N=10) |     Gabon (N=10)      |    Gambia (N=10)    |    Georgia (N=10)     |     Germany (N=10)     |     Ghana (N=10)     |     Greece (N=10)     |      Guam (N=10)       |   Guatemala (N=10)    |    Guinea (N=10)    | Guinea-Bissau (N=10) |     Guyana (N=10)     |    Haiti (N=10)     |    Honduras (N=10)    | Hong Kong, China (N=10) |    Hungary (N=10)     |     Iceland (N=10)     |     India (N=10)      |   Indonesia (N=10)    | Iran, Islamic Republic of (N=10) |      Iraq (N=10)      |     Ireland (N=10)      |     Israel (N=10)     |      Italy (N=10)       |    Jamaica (N=10)     |     Japan (N=10)      |     Jordan (N=10)     |   Kazakhstan (N=10)   |    Kenya (N=10)     | Korea, Democratic People's Republic of (N=10) | Korea, Republic of (N=10) |     Kuwait (N=10)      |   Kyrgyzstan (N=10)   | Lao People's Democratic Republic (N=10) |     Latvia (N=10)     |    Lebanon (N=10)     |   Lesotho (N=10)    |   Liberia (N=10)    |     Libya (N=10)      |   Lithuania (N=10)    |    Luxembourg (N=10)    |   Macau, China (N=10)   |  Madagascar (N=10)  |    Malawi (N=10)    |    Malaysia (N=10)    |    Maldives (N=10)    |     Mali (N=10)     |      Malta (N=10)      |   Mauritania (N=10)   |   Mauritius (N=10)    |     Mexico (N=10)     | Moldova, Republic of (N=10) |    Mongolia (N=10)    |   Montenegro (N=10)   |    Morocco (N=10)     |  Mozambique (N=10)  |    Myanmar (N=10)    |    Namibia (N=10)     |    Nepal (N=10)     |   Netherlands (N=10)    |  New Caledonia (N=10)   |  New Zealand (N=10)   |   Nicaragua (N=10)    |    Niger (N=10)     |    Nigeria (N=10)     | North Macedonia (N=10) |      Norway (N=10)      | Occupied Palestinian Territory (N=10) |      Oman (N=10)      |    Pakistan (N=10)    |     Panama (N=10)     | Papua New Guinea (N=10) |    Paraguay (N=10)    |      Peru (N=10)      |  Philippines (N=10)   |     Poland (N=10)     |    Portugal (N=10)    |   Puerto Rico (N=10)    |      Qatar (N=10)       |    Romania (N=10)     | Russian Federation (N=10) |    Rwanda (N=10)    |  Saint Lucia (N=10)   | Saint Vincent and the Grenadines (N=10) |     Samoa (N=10)      | Sao Tome and Principe (N=10) |   Saudi Arabia (N=10)   |    Senegal (N=10)     |     Serbia (N=10)     | Sierra Leone (N=10) |    Singapore (N=10)     |    Slovakia (N=10)    |    Slovenia (N=10)    | Solomon Islands (N=10) |   Somalia (N=10)    |  South Africa (N=10)  | South Sudan (N=10)  |     Spain (N=10)      |   Sri Lanka (N=10)    |     Sudan (N=10)      |    Suriname (N=10)    |      Sweden (N=10)      |   Switzerland (N=10)    | Syrian Arab Republic (N=10) | Taiwan, China (N=10)  |  Tajikistan (N=10)   | Tanzania, United Republic of (N=10) |    Thailand (N=10)    | Timor-Leste (N=10)  |     Togo (N=10)     |     Tonga (N=10)      | Trinidad and Tobago (N=10) |    Tunisia (N=10)     |     Turkey (N=10)     |  Turkmenistan (N=10)  |    Uganda (N=10)    |    Ukraine (N=10)     | United Arab Emirates (N=10) | United Kingdom (N=10) |  United States (N=10)   | United States Virgin Islands (N=10) |    Uruguay (N=10)     |   Uzbekistan (N=10)   |   Vanuatu (N=10)    | Venezuela, Bolivarian Republic of (N=10) |   Viet Nam (N=10)    | Western Sahara (N=10) |     Yemen (N=10)     |    Zambia (N=10)    |   Zimbabwe (N=10)   |    Total (N=1890)     | p value|
## |:---------------------------|:-------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:-----------------------:|:---------------------:|:---------------------:|:---------------------:|:--------------------:|:---------------------:|:---------------------:|:-----------------------:|:---------------------:|:-------------------:|:---------------------:|:---------------------:|:-----------------------------:|:---------------------:|:---------------------:|:------------------------:|:---------------------:|:-------------------:|:-------------------:|:---------------------:|:-------------------:|:-------------------:|:---------------------:|:---------------------:|:-------------------------------:|:-------------------:|:----------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:--------------------:|:----------------------------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:-----------------------:|:--------------------:|:-------------------------:|:---------------------:|:---------------------:|:---------------------:|:------------------------:|:-------------------:|:---------------------:|:---------------------:|:-------------------:|:---------------------:|:----------------------:|:-----------------------:|:-----------------------:|:---------------------:|:-------------------:|:---------------------:|:----------------------:|:--------------------:|:---------------------:|:----------------------:|:---------------------:|:-------------------:|:--------------------:|:---------------------:|:-------------------:|:---------------------:|:-----------------------:|:---------------------:|:----------------------:|:---------------------:|:---------------------:|:--------------------------------:|:---------------------:|:-----------------------:|:---------------------:|:-----------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:-------------------:|:---------------------------------------------:|:-------------------------:|:----------------------:|:---------------------:|:---------------------------------------:|:---------------------:|:---------------------:|:-------------------:|:-------------------:|:---------------------:|:---------------------:|:-----------------------:|:-----------------------:|:-------------------:|:-------------------:|:---------------------:|:---------------------:|:-------------------:|:----------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------------:|:---------------------:|:---------------------:|:---------------------:|:-------------------:|:--------------------:|:---------------------:|:-------------------:|:-----------------------:|:-----------------------:|:---------------------:|:---------------------:|:-------------------:|:---------------------:|:----------------------:|:-----------------------:|:-------------------------------------:|:---------------------:|:---------------------:|:---------------------:|:-----------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:-----------------------:|:-----------------------:|:---------------------:|:-------------------------:|:-------------------:|:---------------------:|:---------------------------------------:|:---------------------:|:----------------------------:|:-----------------------:|:---------------------:|:---------------------:|:-------------------:|:-----------------------:|:---------------------:|:---------------------:|:----------------------:|:-------------------:|:---------------------:|:-------------------:|:---------------------:|:---------------------:|:---------------------:|:---------------------:|:-----------------------:|:-----------------------:|:---------------------------:|:---------------------:|:--------------------:|:-----------------------------------:|:---------------------:|:-------------------:|:-------------------:|:---------------------:|:--------------------------:|:---------------------:|:---------------------:|:---------------------:|:-------------------:|:---------------------:|:---------------------------:|:---------------------:|:-----------------------:|:-----------------------------------:|:---------------------:|:---------------------:|:-------------------:|:----------------------------------------:|:--------------------:|:---------------------:|:--------------------:|:-------------------:|:-------------------:|:---------------------:|-------:|
## |**Value**                   |                     |                       |                       |                       |                       |                       |                       |                         |                       |                       |                       |                      |                       |                       |                         |                       |                     |                       |                       |                               |                       |                       |                          |                       |                     |                     |                       |                     |                     |                       |                       |                                 |                     |                        |                       |                       |                       |                       |                      |                                          |                       |                       |                       |                       |                       |                         |                      |                           |                       |                       |                       |                          |                     |                       |                       |                     |                       |                        |                         |                         |                       |                     |                       |                        |                      |                       |                        |                       |                     |                      |                       |                     |                       |                         |                       |                        |                       |                       |                                  |                       |                         |                       |                         |                       |                       |                       |                       |                     |                                               |                           |                        |                       |                                         |                       |                       |                     |                     |                       |                       |                         |                         |                     |                     |                       |                       |                     |                        |                       |                       |                       |                             |                       |                       |                       |                     |                      |                       |                     |                         |                         |                       |                       |                     |                       |                        |                         |                                       |                       |                       |                       |                         |                       |                       |                       |                       |                       |                         |                         |                       |                           |                     |                       |                                         |                       |                              |                         |                       |                       |                     |                         |                       |                       |                        |                     |                       |                     |                       |                       |                       |                       |                         |                         |                             |                       |                      |                                     |                       |                     |                     |                       |                            |                       |                       |                       |                     |                       |                             |                       |                         |                                     |                       |                       |                     |                                          |                      |                       |                      |                     |                     |                       | < 0.001|
## |&nbsp;&nbsp;&nbsp;Mean (SD) | 9359.800 (409.767)  | 31149.300 (1807.674)  | 41751.200 (2049.561)  | 20087.400 (1496.409)  | 56680.200 (1899.561)  | 30620.400 (4954.162)  | 95269.800 (3529.443)  |  109305.300 (1911.516)  |  30068.000 (797.536)  | 72694.600 (4674.283)  | 81722.900 (3536.810)  | 9491.000 (1240.419)  |  32197.400 (301.566)  | 36578.100 (1018.088)  |  120154.300 (2234.551)  | 17926.100 (1031.117)  | 7477.800 (427.736)  | 21529.800 (1839.159)  | 16923.600 (1553.025)  |     42641.600 (1953.918)      | 44468.300 (1253.839)  |  33498.800 (670.081)  |  139504.600 (7527.023)   | 46287.500 (2425.957)  | 5603.000 (463.809)  | 1945.500 (123.978)  | 13983.900 (2165.098)  | 6244.900 (989.442)  | 8102.100 (408.304)  | 91709.600 (2340.117)  |  17638.100 (562.342)  |       2574.300 (465.785)        | 4716.100 (329.496)  |  99632.700 (4065.382)  | 50566.800 (1502.980)  | 22150.900 (4551.050)  | 29086.700 (1264.697)  |  12060.400 (105.097)  |  9859.500 (473.323)  |            3047.300 (286.037)            | 41019.200 (2648.200)  | 65195.900 (2231.562)  | 32205.600 (1875.759)  | 58245.300 (1333.154)  | 74505.500 (3296.985)  |  111191.800 (3707.176)  | 11930.900 (1553.228) |   36418.200 (2751.243)    | 25427.500 (1271.958)  | 38081.500 (3300.784)  |  19893.500 (821.929)  |  81477.500 (19929.435)   | 3363.700 (289.594)  | 65120.200 (3631.592)  |  34511.200 (554.051)  | 3820.100 (656.239)  | 30480.600 (4098.078)  | 102079.600 (2196.284)  |  107105.400 (3048.820)  |  78378.700 (2733.572)   | 58494.200 (1898.454)  | 7170.000 (356.961)  | 25338.500 (3242.980)  | 102478.200 (2217.853)  | 11653.200 (1169.703) | 86100.800 (1938.579)  | 100326.600 (3141.186)  |  19941.600 (533.342)  | 6631.900 (686.898)  |  4597.800 (192.511)  | 25081.500 (2284.967)  | 4587.100 (100.669)  |  12930.500 (247.228)  |  111177.600 (5670.623)  | 64789.800 (2278.646)  |  90664.900 (6745.689)  | 15609.200 (2759.765)  | 21523.700 (2135.827)  |       46277.800 (2625.652)       | 45007.300 (2688.477)  | 151458.000 (25626.265)  | 90668.100 (3288.615)  |  110329.100 (1756.229)  | 22488.400 (1019.681)  | 77339.600 (1011.766)  | 46531.700 (1247.565)  | 48885.900 (4637.063)  | 9076.700 (415.110)  |               3099.700 (87.979)               |   75100.600 (3727.882)    | 101992.500 (10692.671) | 12081.100 (1447.326)  |          12397.300 (1751.755)           | 56993.000 (4241.074)  | 52465.600 (4852.991)  | 7782.100 (391.886)  | 3573.900 (206.147)  | 50145.100 (14979.567) | 66282.900 (4963.387)  |  240620.100 (5323.347)  | 222396.300 (25455.741)  |  3145.800 (71.738)  |  2543.900 (43.337)  | 53041.300 (3880.721)  | 36540.300 (2541.821)  | 6269.700 (408.060)  | 88027.600 (10017.010)  |  20565.300 (548.391)  | 45163.600 (3542.535)  |  45337.200 (862.676)  |    21728.100 (2713.828)     | 25779.700 (3896.292)  | 52702.100 (1493.241)  | 22750.900 (2045.054)  | 2847.600 (263.887)  | 8974.400 (1721.896)  | 32745.600 (1471.076)  | 5296.300 (500.248)  |  106911.500 (3052.767)  |  115686.300 (2424.126)  | 77362.800 (2724.652)  |  12539.100 (580.275)  | 3046.000 (282.385)  | 17760.100 (1420.669)  |  43285.800 (487.479)   |  120820.400 (3018.868)  |          26748.200 (710.554)          | 61284.600 (8464.270)  |  13182.700 (869.023)  | 60564.800 (6075.044)  |  13374.500 (1426.162)   | 25050.800 (1535.376)  | 21821.400 (1510.875)  | 17944.000 (2513.695)  | 62406.300 (4738.862)  | 70615.700 (1156.234)  |  119226.900 (2531.834)  |  130025.300 (4546.875)  | 55501.900 (6970.748)  |   52747.800 (2313.555)    | 3731.000 (433.268)  |  32063.000 (968.601)  |           28846.900 (396.818)           | 24598.700 (1265.057)  |     12769.300 (767.219)      |  125558.000 (4739.288)  | 12288.800 (1039.129)  | 34875.900 (1383.014)  | 5139.100 (626.473)  |  148445.400 (8328.323)  | 64797.400 (2474.990)  | 75999.800 (3682.700)  |   4630.200 (162.787)   |  1479.100 (40.534)  |  44426.100 (724.253)  | 5362.800 (835.670)  | 95101.200 (1872.262)  | 29645.400 (3673.821)  |  17524.100 (556.187)  | 49739.700 (2727.299)  |  104597.600 (3875.188)  |  120116.500 (2008.969)  |    14843.200 (4873.076)     | 91608.000 (4754.108)  | 11399.800 (1755.713) |         4955.100 (475.438)          | 28804.100 (3106.600)  | 8185.800 (352.699)  | 4250.600 (366.544)  | 19423.500 (1611.412)  |    59071.700 (2007.947)    | 34456.800 (1149.159)  | 74061.000 (5835.638)  | 31790.500 (6150.547)  | 5654.800 (153.149)  | 27801.400 (1234.782)  |    89519.600 (8185.854)     | 90900.600 (1395.549)  |  122450.300 (2739.975)  |        99258.100 (10218.263)        | 42719.200 (3232.592)  | 14111.000 (2080.878)  | 7457.800 (119.772)  |          63608.600 (17495.907)           | 10912.800 (1663.980) |  17264.800 (452.308)  | 13311.500 (4061.056) | 9354.500 (308.728)  | 6294.500 (569.730)  | 45584.250 (42107.871) |        |
## |&nbsp;&nbsp;&nbsp;Range     | 8794.000 - 9943.000 | 27399.000 - 33439.000 | 38950.000 - 43699.000 | 17297.000 - 21705.000 | 52790.000 - 58957.000 | 25297.000 - 40102.000 | 89581.000 - 99210.000 | 106515.000 - 112371.000 | 29124.000 - 31231.000 | 67086.000 - 78538.000 | 76456.000 - 86323.000 | 7709.000 - 11534.000 | 31445.000 - 32495.000 | 34587.000 - 37874.000 | 116249.000 - 122800.000 | 16332.000 - 19317.000 | 6851.000 - 8229.000 | 18025.000 - 23723.000 | 14384.000 - 18491.000 |     39350.000 - 45032.000     | 42048.000 - 45924.000 | 32677.000 - 34525.000 | 129057.000 - 150120.000  | 41866.000 - 49625.000 | 4783.000 - 6243.000 | 1763.000 - 2110.000 | 11101.000 - 17286.000 | 4818.000 - 7774.000 | 7522.000 - 8612.000 | 87797.000 - 94634.000 | 16941.000 - 18867.000 |       2141.000 - 3376.000       | 4290.000 - 5154.000 | 93378.000 - 104611.000 | 47690.000 - 52153.000 | 15687.000 - 29363.000 | 26947.000 - 31182.000 | 11887.000 - 12259.000 | 8993.000 - 10454.000 |           2525.000 - 3335.000            | 37234.000 - 44074.000 | 60813.000 - 68355.000 | 28996.000 - 34638.000 | 55560.000 - 59721.000 | 70703.000 - 80539.000 | 105854.000 - 116692.000 | 9882.000 - 14559.000 |   33283.000 - 40628.000   | 24012.000 - 27674.000 | 34212.000 - 43931.000 | 18808.000 - 21131.000 |  51613.000 - 105037.000  | 3003.000 - 4051.000 | 61153.000 - 72479.000 | 33789.000 - 35497.000 | 2882.000 - 4790.000 | 25197.000 - 35502.000 | 99852.000 - 105600.000 | 102274.000 - 111772.000 |  75466.000 - 83209.000  | 55421.000 - 60495.000 | 6825.000 - 8056.000 | 20717.000 - 31066.000 | 99349.000 - 105427.000 | 9258.000 - 13290.000 | 83401.000 - 88737.000 | 96508.000 - 104874.000 | 18467.000 - 20380.000 | 5779.000 - 7704.000 | 4360.000 - 4909.000  | 21370.000 - 28543.000 | 4368.000 - 4706.000 | 12638.000 - 13445.000 | 103893.000 - 119741.000 | 62705.000 - 70088.000 | 84788.000 - 103296.000 | 11945.000 - 19693.000 | 18360.000 - 24425.000 |      41360.000 - 49423.000       | 40381.000 - 48324.000 | 124610.000 - 187658.000 | 86383.000 - 96573.000 | 108643.000 - 113700.000 | 20752.000 - 23592.000 | 75611.000 - 78759.000 | 45339.000 - 48684.000 | 41390.000 - 56446.000 | 8580.000 - 9848.000 |              2899.000 - 3192.000              |   70117.000 - 81060.000   | 88471.000 - 115511.000 | 10138.000 - 14264.000 |          9843.000 - 14887.000           | 50838.000 - 64221.000 | 44309.000 - 60334.000 | 6995.000 - 8304.000 | 3260.000 - 3910.000 | 30085.000 - 80453.000 | 59615.000 - 75717.000 | 231570.000 - 249868.000 | 194060.000 - 265200.000 | 3058.000 - 3267.000 | 2475.000 - 2600.000 | 48813.000 - 59364.000 | 34120.000 - 41621.000 | 5743.000 - 6869.000 | 77607.000 - 103313.000 | 19534.000 - 21204.000 | 40034.000 - 51105.000 | 43960.000 - 46390.000 |    18570.000 - 26506.000    | 18584.000 - 29905.000 | 50494.000 - 54911.000 | 19698.000 - 25322.000 | 2374.000 - 3078.000 | 6689.000 - 11548.000 | 31092.000 - 35211.000 | 4529.000 - 6055.000 | 103118.000 - 110932.000 | 110049.000 - 118487.000 | 73912.000 - 82100.000 | 11648.000 - 13422.000 | 2574.000 - 3385.000 | 15288.000 - 19134.000 | 42419.000 - 44047.000  | 117219.000 - 124972.000 |         25920.000 - 28082.000         | 52740.000 - 78622.000 | 12245.000 - 14556.000 | 49249.000 - 67184.000 |  11587.000 - 14858.000  | 22207.000 - 26774.000 | 18832.000 - 23344.000 | 14955.000 - 21832.000 | 55547.000 - 71046.000 | 68574.000 - 72660.000 | 115354.000 - 122964.000 | 123661.000 - 138639.000 | 46495.000 - 66848.000 |   48634.000 - 56659.000   | 3084.000 - 4468.000 | 30883.000 - 33876.000 |          28229.000 - 29420.000          | 23147.000 - 26257.000 |    11737.000 - 13640.000     | 119151.000 - 133454.000 | 11154.000 - 13910.000 | 33139.000 - 36958.000 | 4267.000 - 6278.000 | 136243.000 - 160348.000 | 61033.000 - 68993.000 | 71054.000 - 82608.000 |  4184.000 - 4750.000   | 1419.000 - 1535.000 | 43508.000 - 45455.000 | 4286.000 - 6365.000 | 91652.000 - 97280.000 | 23511.000 - 34990.000 | 16375.000 - 18329.000 | 46471.000 - 52974.000 | 100470.000 - 110270.000 | 117860.000 - 123736.000 |    11576.000 - 24648.000    | 85368.000 - 99189.000 | 9158.000 - 14501.000 |         4206.000 - 5623.000         | 24542.000 - 33502.000 | 7704.000 - 8632.000 | 3701.000 - 4771.000 | 17118.000 - 21350.000 |   56463.000 - 60916.000    | 32486.000 - 36031.000 | 64341.000 - 81694.000 | 21669.000 - 40307.000 | 5340.000 - 5923.000 | 25419.000 - 29280.000 |    77311.000 - 98205.000    | 88575.000 - 92646.000 | 118879.000 - 127046.000 |       92961.000 - 122431.000        | 37451.000 - 46795.000 | 11089.000 - 17181.000 | 7268.000 - 7674.000 |          28945.000 - 79334.000           | 8833.000 - 13817.000 | 16473.000 - 17826.000 | 8678.000 - 18921.000 | 8880.000 - 9734.000 | 4984.000 - 6891.000 | 1419.000 - 265200.000 |        |

(1-3) Changes in the distribution of the dependent variable between 2010 and 2019, by country

library(CGPfunctions)
library(magrittr)

## 
## Attaching package: 'magrittr'

## The following object is masked from 'package:arsenal':
## 
##     set_attr

library(dplyr)

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

library(ggplot2)
lp_slope <- lpdata %>%
  filter(Year %in% c(2010, 2015, 2019) &
           Country %in% c("Afghanistan", "Argentina", "Australia", "Austria", "Bahamas", "Bangladesh", "Belgium", "Bhutan", "Bolivia", "Brazil", "Brunei Darussalam", "Cambodia", "Canada", "Chad", "Chile", "China", "Chroatia",  "Djibouti", "Egypt", "Ethiopia", "France", "Gabon", "Germany", "Guatemala", "Honduras", "Hungary", "India", "Iraq", "Japan", "Korea, Republic of", "Luxembourg", "Macau, China", "Malaysia", "Mexico", "Myanmar", "Nepal", "Netherlands", "Pakistan", "Philippines", "Russian Federation", "Singapore", "South Africa", "Sri Lanka", "Switzerand", "Turkey", "Uganda", "United States", "Yemen", "Zimbabwe" )) %>%
  mutate(Year = factor(Year),
         Value = round(Value)) 

newggslopegraph(lp_slope, Year, Value, Country) +labs(title="Change in labour productivity, by country, from 2010 to 2019", check_overlap = T)

## 
## Converting 'Year' to an ordered factor

## Warning: ggrepel: 2 unlabeled data points (too many overlaps). Consider
## increasing max.overlaps

## Warning: ggrepel: 2 unlabeled data points (too many overlaps). Consider
## increasing max.overlaps

Table 1-1 above suggests that there was an overall 6.75% increase in the level of labour productivity between 2010 and 2019 across the globe. Figure 1-3 shows that labour productivity has generally increased in most of the countries at a gradual pace.

(2-1) The distribution of the independent variable by year

str(pedata)

## 'data.frame':    1780 obs. of  3 variables:
##  $ Country: chr  "Aruba" "Aruba" "Aruba" "Aruba" ...
##  $ Year   : int  2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 ...
##  $ Value  : num  91.8 91.6 92.4 NA NA ...

pedata_table <- tableby(Year ~ Value, data = pedata) 
summary(pedata_table, title = "Private Education Data")

## 
## 
## Table: Private Education Data
## 
## |                            |  2010 (N=178)   |  2011 (N=178)   |  2012 (N=178)   |  2013 (N=178)   |  2014 (N=178)   |  2015 (N=178)   |  2016 (N=178)   |  2017 (N=178)   |  2018 (N=178)   |  2019 (N=178)   | Total (N=1780)  | p value|
## |:---------------------------|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|-------:|
## |**Value**                   |                 |                 |                 |                 |                 |                 |                 |                 |                 |                 |                 |   0.994|
## |&nbsp;&nbsp;&nbsp;N-Miss    |       55        |       47        |       54        |       54        |       47        |       45        |       48        |       54        |       56        |       119       |       579       |        |
## |&nbsp;&nbsp;&nbsp;Mean (SD) | 19.039 (19.558) | 18.531 (18.821) | 18.929 (19.579) | 19.410 (19.361) | 19.426 (18.624) | 19.667 (19.183) | 18.752 (18.339) | 19.386 (19.633) | 18.499 (18.132) | 22.024 (21.684) | 19.219 (19.109) |        |
## |&nbsp;&nbsp;&nbsp;Range     | 0.077 - 95.356  | 0.271 - 95.347  | 0.000 - 95.516  | 0.014 - 95.543  | 0.041 - 95.742  | 0.037 - 95.952  | 0.054 - 95.919  | 0.000 - 96.062  | 0.089 - 95.986  | 0.146 - 96.253  | 0.000 - 96.253  |        |

(2-2) The distribution of the independent variable by country

pedata_table_2 <- tableby(Country ~ Value, data = pedata) 
summary(pedata_table_2, title = "Private Education Data")

## 
## 
## Table: Private Education Data
## 
## |                            | Afghanistan (N=10) | Albania (N=10) | Algeria (N=10) | American Samoa (N=10) | Andorra (N=10) |  Angola (N=10)  | Antigua and Barbuda (N=10) | Argentina (N=10) |  Aruba (N=10)   | Australia (N=10) | Austria (N=10) | Azerbaijan (N=10) | Bahamas, The (N=10) | Bahrain (N=10)  | Bangladesh (N=10) | Barbados (N=10) | Belarus (N=10) | Belgium (N=10)  |  Belize (N=10)  |  Benin (N=10)   | Bermuda (N=10)  |  Bhutan (N=10)  | Bolivia (N=10)  | Bosnia and Herzegovina (N=10) | Botswana (N=10) |  Brazil (N=10)  | British Virgin Islands (N=10) | Brunei Darussalam (N=10) | Bulgaria (N=10) | Burkina Faso (N=10) | Burundi (N=10) | Cabo Verde (N=10) | Cambodia (N=10) | Cameroon (N=10) | Canada (N=10) | Cayman Islands (N=10) | Central African Republic (N=10) |   Chad (N=10)   |  Chile (N=10)   |  China (N=10)  | Colombia (N=10) | Comoros (N=10)  | Congo, Dem. Rep. (N=10) | Congo, Rep. (N=10) | Costa Rica (N=10) | Cote d'Ivoire (N=10) | Croatia (N=10) |  Cyprus (N=10)  | Czech Republic (N=10) | Denmark (N=10)  | Djibouti (N=10) | Dominica (N=10) | Dominican Republic (N=10) | Ecuador (N=10)  | Egypt, Arab Rep. (N=10) | El Salvador (N=10) | Eritrea (N=10) | Estonia (N=10) | Ethiopia (N=10) | Fiji (N=10) | Finland (N=10) |  France (N=10)  | Georgia (N=10) | Germany (N=10) |  Ghana (N=10)   | Gibraltar (N=10) | Greece (N=10) | Grenada (N=10)  | Guatemala (N=10) |  Guinea (N=10)  | Guyana (N=10) | Honduras (N=10) | Hong Kong SAR, China (N=10) | Hungary (N=10)  | Iceland (N=10)  |  India (N=10)   | Indonesia (N=10) | Iran, Islamic Rep. (N=10) | Ireland (N=10) |  Israel (N=10)  | Italy (N=10)  | Jamaica (N=10) |  Japan (N=10)   |  Jordan (N=10)  | Kazakhstan (N=10) | Kenya (N=10) | Korea, Rep. (N=10) |  Kuwait (N=10)  | Kyrgyz Republic (N=10) | Lao PDR (N=10) | Latvia (N=10) | Lebanon (N=10)  | Lesotho (N=10) | Liberia (N=10)  | Libya (N=10) | Liechtenstein (N=10) | Lithuania (N=10) | Luxembourg (N=10) | Macao SAR, China (N=10) | Madagascar (N=10) | Malawi (N=10)  | Malaysia (N=10) | Maldives (N=10) |   Mali (N=10)   |  Malta (N=10)   | Marshall Islands (N=10) | Mauritania (N=10) | Mauritius (N=10) |  Mexico (N=10)  | Moldova (N=10) |  Monaco (N=10)  | Mongolia (N=10) | Morocco (N=10) | Mozambique (N=10) | Myanmar (N=10) | Namibia (N=10) | Nepal (N=10) | Netherlands (N=10) | New Zealand (N=10) | Nicaragua (N=10) |  Niger (N=10)   | Nigeria (N=10)  | North Macedonia (N=10) | Norway (N=10) |  Oman (N=10)   | Pakistan (N=10) | Palau (N=10) |  Panama (N=10)  | Paraguay (N=10) |   Peru (N=10)   | Philippines (N=10) | Poland (N=10)  | Portugal (N=10) | Puerto Rico (N=10) |  Qatar (N=10)   | Romania (N=10) | Russian Federation (N=10) |  Rwanda (N=10)  |  Samoa (N=10)   | Saudi Arabia (N=10) | Senegal (N=10)  | Serbia (N=10) | Seychelles (N=10) | Sierra Leone (N=10) | Singapore (N=10) | Slovak Republic (N=10) | Slovenia (N=10) | Solomon Islands (N=10) | South Africa (N=10) |  Spain (N=10)   | Sri Lanka (N=10) | St. Lucia (N=10) |  Sudan (N=10)   | Suriname (N=10) |  Sweden (N=10)  | Switzerland (N=10) | Syrian Arab Republic (N=10) | Tajikistan (N=10) | Tanzania (N=10) | Thailand (N=10) | Timor-Leste (N=10) |   Togo (N=10)   |  Tonga (N=10)   | Tunisia (N=10) | Turkey (N=10) | Turks and Caicos Islands (N=10) |  Tuvalu (N=10)  | Uganda (N=10) | Ukraine (N=10) | United Arab Emirates (N=10) | United Kingdom (N=10) | United States (N=10) | Uruguay (N=10)  | Uzbekistan (N=10) | Venezuela, RB (N=10) | West Bank and Gaza (N=10) | Yemen, Rep. (N=10) | Zimbabwe (N=10) | Total (N=1780)  | p value|
## |:---------------------------|:------------------:|:--------------:|:--------------:|:---------------------:|:--------------:|:---------------:|:--------------------------:|:----------------:|:---------------:|:----------------:|:--------------:|:-----------------:|:-------------------:|:---------------:|:-----------------:|:---------------:|:--------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:-----------------------------:|:---------------:|:---------------:|:-----------------------------:|:------------------------:|:---------------:|:-------------------:|:--------------:|:-----------------:|:---------------:|:---------------:|:-------------:|:---------------------:|:-------------------------------:|:---------------:|:---------------:|:--------------:|:---------------:|:---------------:|:-----------------------:|:------------------:|:-----------------:|:--------------------:|:--------------:|:---------------:|:---------------------:|:---------------:|:---------------:|:---------------:|:-------------------------:|:---------------:|:-----------------------:|:------------------:|:--------------:|:--------------:|:---------------:|:-----------:|:--------------:|:---------------:|:--------------:|:--------------:|:---------------:|:----------------:|:-------------:|:---------------:|:----------------:|:---------------:|:-------------:|:---------------:|:---------------------------:|:---------------:|:---------------:|:---------------:|:----------------:|:-------------------------:|:--------------:|:---------------:|:-------------:|:--------------:|:---------------:|:---------------:|:-----------------:|:------------:|:------------------:|:---------------:|:----------------------:|:--------------:|:-------------:|:---------------:|:--------------:|:---------------:|:------------:|:--------------------:|:----------------:|:-----------------:|:-----------------------:|:-----------------:|:--------------:|:---------------:|:---------------:|:---------------:|:---------------:|:-----------------------:|:-----------------:|:----------------:|:---------------:|:--------------:|:---------------:|:---------------:|:--------------:|:-----------------:|:--------------:|:--------------:|:------------:|:------------------:|:------------------:|:----------------:|:---------------:|:---------------:|:----------------------:|:-------------:|:--------------:|:---------------:|:------------:|:---------------:|:---------------:|:---------------:|:------------------:|:--------------:|:---------------:|:------------------:|:---------------:|:--------------:|:-------------------------:|:---------------:|:---------------:|:-------------------:|:---------------:|:-------------:|:-----------------:|:-------------------:|:----------------:|:----------------------:|:---------------:|:----------------------:|:-------------------:|:---------------:|:----------------:|:----------------:|:---------------:|:---------------:|:---------------:|:------------------:|:---------------------------:|:-----------------:|:---------------:|:---------------:|:------------------:|:---------------:|:---------------:|:--------------:|:-------------:|:-------------------------------:|:---------------:|:-------------:|:--------------:|:---------------------------:|:---------------------:|:--------------------:|:---------------:|:-----------------:|:--------------------:|:-------------------------:|:------------------:|:---------------:|:---------------:|-------:|
## |**Value**                   |                    |                |                |                       |                |                 |                            |                  |                 |                  |                |                   |                     |                 |                   |                 |                |                 |                 |                 |                 |                 |                 |                               |                 |                 |                               |                          |                 |                     |                |                   |                 |                 |               |                       |                                 |                 |                 |                |                 |                 |                         |                    |                   |                      |                |                 |                       |                 |                 |                 |                           |                 |                         |                    |                |                |                 |             |                |                 |                |                |                 |                  |               |                 |                  |                 |               |                 |                             |                 |                 |                 |                  |                           |                |                 |               |                |                 |                 |                   |              |                    |                 |                        |                |               |                 |                |                 |              |                      |                  |                   |                         |                   |                |                 |                 |                 |                 |                         |                   |                  |                 |                |                 |                 |                |                   |                |                |              |                    |                    |                  |                 |                 |                        |               |                |                 |              |                 |                 |                 |                    |                |                 |                    |                 |                |                           |                 |                 |                     |                 |               |                   |                     |                  |                        |                 |                        |                     |                 |                  |                  |                 |                 |                 |                    |                             |                   |                 |                 |                    |                 |                 |                |               |                                 |                 |               |                |                             |                       |                      |                 |                   |                      |                           |                    |                 |                 |        |
## |&nbsp;&nbsp;&nbsp;N-Miss    |         3          |       3        |       8        |           4           |       1        |        7        |             3              |        2         |        7        |        6         |       1        |         8         |          1          |        0        |         2         |        2        |       1        |        1        |        2        |        5        |        4        |        1        |        1        |               0               |       10        |        1        |               1               |            1             |        1        |          0          |       0        |         1         |       10        |        4        |       1       |           6           |                8                |        2        |        1        |       0        |        1        |        6        |            6            |         10         |         0         |          4           |       1        |        1        |           2           |        1        |        1        |        6        |             0             |        1        |            5            |         1          |       3        |       1        |        7        |     10      |       1        |        1        |       3        |       1        |        1        |        7         |       1       |        4        |        0         |        8        |       7       |        1        |              0              |        2        |        1        |        4        |        1         |             3             |       2        |        1        |       1       |       1        |        1        |        2        |         0         |      10      |         1          |        5        |           4            |       1        |       1       |        0        |       4        |        8        |      10      |          2           |        1         |         1         |            0            |         2         |       4        |        0        |        8        |        4        |        1        |            8            |         1         |        0         |        1        |       0        |        0        |        9        |       7        |         3         |       6        |       10       |      10      |         4          |         1          |        9         |        4        |        3        |           3            |       1       |       2        |        0        |      10      |        4        |        6        |        1        |         6          |       1        |        1        |         2          |        0        |       1        |             2             |        0        |        5        |          5          |        8        |       0       |         0         |          4          |        7         |           1            |        1        |           7            |          3          |        1        |        6         |        0         |        4        |        3        |        1        |         2          |              6              |         8         |        6        |        0        |         0          |        8        |        5        |       4        |       3       |                8                |        7        |      10       |       0        |              8              |           2           |          1           |        2        |         2         |          2           |             0             |         6          |        9        |       579       |        |
## |&nbsp;&nbsp;&nbsp;Mean (SD) |   2.788 (1.134)    | 7.758 (1.183)  | 0.174 (0.137)  |     2.263 (0.322)     | 2.631 (0.367)  | 14.344 (6.173)  |       18.131 (0.825)       |  26.151 (0.516)  | 91.909 (0.424)  |  43.726 (6.028)  | 10.028 (0.364) |  12.588 (0.428)   |   26.708 (4.131)    | 24.260 (1.682)  |  93.616 (2.461)   |  6.326 (0.633)  | 0.477 (0.039)  | 58.376 (0.422)  | 64.342 (3.059)  | 16.167 (2.276)  | 43.726 (0.868)  | 11.124 (0.807)  | 12.180 (0.477)  |         2.067 (0.451)         |       NA        | 13.822 (0.581)  |        17.477 (0.932)         |      15.549 (0.963)      |  3.082 (1.826)  |   40.556 (0.983)    | 8.315 (0.840)  |  10.281 (2.662)   |       NA        | 27.138 (1.069)  | 7.586 (0.452) |    30.090 (2.950)     |         22.813 (1.020)          | 18.890 (4.880)  | 60.612 (1.383)  | 11.192 (1.261) | 20.655 (0.345)  | 51.868 (2.385)  |     16.603 (1.440)      |         NA         |   9.096 (0.523)   |    51.299 (0.628)    | 2.026 (0.372)  | 17.855 (0.423)  |     9.148 (0.598)     | 14.083 (0.903)  |  9.869 (0.882)  | 30.629 (2.235)  |      19.226 (1.306)       | 29.092 (3.036)  |      7.564 (0.538)      |   16.775 (0.589)   | 6.074 (1.234)  | 3.636 (0.263)  | 10.760 (3.909)  |     NA      | 12.726 (2.777) | 25.731 (0.446)  | 10.376 (0.405) | 9.121 (0.391)  | 16.210 (0.590)  |  7.393 (2.979)   | 4.439 (0.219) | 62.999 (1.021)  |  62.425 (1.013)  | 32.776 (9.227)  | 7.625 (1.264) | 26.624 (1.761)  |       18.452 (1.686)        | 18.926 (4.413)  | 13.738 (0.946)  | 50.311 (1.312)  |  41.804 (0.712)  |      12.432 (1.045)       | 0.585 (0.211)  | 11.599 (0.493)  | 7.281 (0.673) | 2.946 (1.355)  | 19.792 (0.557)  | 19.945 (1.387)  |   5.176 (0.396)   |      NA      |   31.279 (0.281)   | 34.357 (1.821)  |     2.893 (0.110)      | 2.969 (0.234)  | 2.360 (0.950) | 60.237 (1.180)  | 1.380 (0.619)  | 59.174 (1.140)  |      NA      |    3.702 (0.911)     |  2.294 (0.905)   |  18.195 (0.356)   |     95.768 (0.314)      |  40.326 (2.779)   | 8.120 (1.680)  |  8.522 (2.340)  |  4.980 (0.296)  | 37.523 (4.863)  | 34.909 (2.688)  |     19.410 (1.943)      |  26.544 (1.673)   |  57.712 (0.988)  | 13.339 (0.244)  | 1.518 (0.263)  | 27.273 (4.752)  |   7.205 (NA)    | 10.331 (0.391) |  11.443 (1.566)   | 4.052 (1.916)  |       NA       |      NA      |   5.294 (1.602)    |   10.862 (3.288)   |   21.834 (NA)    | 17.672 (1.896)  | 21.011 (2.203)  |     0.980 (0.476)      | 7.387 (0.435) | 10.760 (2.027) | 32.765 (1.887)  |      NA      | 16.292 (0.158)  | 21.507 (0.345)  | 28.005 (2.204)  |   20.165 (3.090)   | 8.926 (3.432)  | 16.831 (0.535)  |   24.641 (1.680)   | 44.365 (3.705)  | 1.375 (0.304)  |       1.122 (0.205)       | 16.404 (4.094)  | 32.542 (1.069)  |   12.290 (0.637)    | 22.118 (1.615)  | 0.592 (0.180) |  10.194 (2.259)   |    8.874 (1.448)    |  4.791 (0.496)   |     10.725 (0.756)     |  2.644 (1.164)  |     31.609 (2.154)     |    4.256 (0.458)    | 28.230 (1.222)  |  7.043 (0.412)   |  3.352 (0.302)   | 16.341 (2.905)  |  0.869 (0.134)  | 17.778 (1.527)  |   10.984 (1.709)   |        3.905 (0.245)        |   1.160 (0.126)   | 18.660 (0.424)  | 12.992 (2.841)  |   24.673 (0.930)   | 25.141 (2.645)  | 67.265 (2.356)  | 6.337 (1.248)  | 5.078 (2.055) |         18.675 (5.404)          | 18.168 (10.304) |      NA       | 0.436 (0.096)  |       64.991 (2.031)        |    56.658 (20.254)    |    8.426 (0.397)     | 12.424 (0.626)  |   0.056 (0.046)   |    30.763 (2.079)    |       6.605 (0.643)       |   3.960 (0.411)    |   77.410 (NA)   | 19.219 (19.109) |        |
## |&nbsp;&nbsp;&nbsp;Range     |   1.274 - 4.458    | 6.144 - 9.463  | 0.077 - 0.271  |     1.706 - 2.645     | 2.045 - 3.058  | 10.584 - 21.468 |      16.712 - 19.505       | 25.366 - 26.830  | 91.570 - 92.384 | 40.457 - 52.759  | 9.488 - 10.542 |  12.285 - 12.891  |   17.744 - 31.064   | 21.249 - 26.118 |  87.602 - 95.115  |  5.316 - 7.301  | 0.421 - 0.559  | 57.616 - 58.765 | 60.622 - 70.352 | 12.972 - 18.682 | 42.829 - 45.247 | 10.052 - 12.503 | 11.499 - 12.754 |         1.457 - 2.748         |       NA        | 12.878 - 14.981 |        15.913 - 18.830        |     13.523 - 16.813      |  1.030 - 5.374  |   38.777 - 41.857   | 6.859 - 9.252  |  7.444 - 13.711   |       NA        | 25.442 - 28.260 | 6.985 - 8.352 |    27.726 - 34.379    |         22.091 - 23.534         | 14.821 - 26.280 | 57.909 - 61.913 | 9.830 - 13.650 | 20.214 - 21.185 | 49.653 - 55.012 |     14.957 - 18.470     |         NA         |   7.938 - 9.656   |   50.566 - 52.069    | 1.469 - 2.354  | 17.244 - 18.646 |    8.170 - 10.064     | 12.914 - 15.639 | 8.867 - 11.617  | 28.702 - 33.580 |      17.805 - 21.580      | 25.978 - 33.388 |      6.978 - 8.370      |  16.135 - 18.007   | 4.554 - 7.471  | 3.314 - 4.165  | 6.620 - 14.387  |     NA      | 8.310 - 14.859 | 25.205 - 26.169 | 9.945 - 11.070 | 8.480 - 9.632  | 15.403 - 17.184 |  4.381 - 10.338  | 4.205 - 4.811 | 61.594 - 64.453 | 60.309 - 63.445  | 26.251 - 39.300 | 6.235 - 8.706 | 24.483 - 30.192 |       16.470 - 21.012       | 12.864 - 22.444 | 12.290 - 14.970 | 47.995 - 51.888 | 40.913 - 43.356  |      10.527 - 13.556      | 0.213 - 0.747  | 10.517 - 12.096 | 6.761 - 8.520 | 1.784 - 5.150  | 19.132 - 20.706 | 18.583 - 21.727 |   4.671 - 5.718   |      NA      |  30.752 - 31.669   | 31.516 - 36.371 |     2.720 - 3.006      | 2.690 - 3.312  | 1.151 - 3.750 | 58.117 - 62.203 | 0.850 - 2.559  | 58.368 - 59.981 |      NA      |    2.508 - 5.064     |  1.096 - 3.461   |  17.717 - 18.804  |     95.347 - 96.253     |  35.995 - 43.098  | 5.919 - 10.232 | 4.487 - 11.253  |  4.770 - 5.189  | 31.260 - 43.767 | 28.945 - 37.980 |     18.036 - 20.784     |  24.565 - 29.360  | 56.587 - 59.596  | 13.068 - 13.790 | 1.250 - 2.027  | 21.741 - 32.582 |  7.205 - 7.205  | 9.940 - 10.722 |  9.477 - 13.329   | 1.268 - 5.580  |       NA       |      NA      |   3.320 - 7.177    |   9.082 - 19.485   | 21.834 - 21.834  | 14.816 - 19.393 | 18.699 - 24.182 |     0.000 - 1.510      | 6.904 - 8.165 | 6.975 - 13.068 | 30.878 - 35.830 |      NA      | 16.111 - 16.472 | 21.007 - 21.802 | 24.099 - 30.050 |  18.079 - 24.730   | 4.148 - 11.467 | 16.075 - 17.575 |  21.278 - 27.205   | 38.603 - 49.181 | 1.067 - 1.838  |       0.763 - 1.306       | 11.335 - 24.246 | 30.904 - 33.827 |   11.464 - 13.036   | 20.976 - 23.260 | 0.413 - 0.948 |  6.738 - 12.897   |   6.971 - 10.790    |  4.228 - 5.166   |     9.621 - 11.885     |  1.485 - 4.192  |    29.846 - 34.010     |    3.679 - 5.038    | 26.944 - 30.233 |  6.441 - 7.329   |  2.828 - 3.746   | 13.254 - 20.347 |  0.778 - 1.157  | 16.291 - 20.967 |   7.370 - 12.080   |        3.596 - 4.191        |   1.071 - 1.249   | 18.047 - 19.016 | 10.481 - 16.784 |  23.338 - 26.490   | 23.271 - 27.011 | 64.221 - 69.297 | 4.766 - 7.467  | 3.039 - 7.816 |         14.854 - 22.496         | 6.661 - 26.540  |      NA       | 0.368 - 0.647  |       63.555 - 66.427       |    29.316 - 74.760    |    7.911 - 8.953     | 11.423 - 13.002 |   0.000 - 0.146   |   28.299 - 33.311    |       5.450 - 7.286       |   3.468 - 4.453    | 77.410 - 77.410 | 0.000 - 96.253  |        |

(2-3) Changes in the distribution of the independent variable between 2010 and 2018, by country (The figure presents the year 2018 instead of 2019 as many countries miss the latest data for the year)

pe_slope <- pedata %>%
  filter(Year %in% c(2010, 2015, 2018) &
           Country %in% c("Andorra", "Austria", "Bangladesh", "Brundi", "Belgium", "Bulgaria", "Bolivia", "Brazil", "Brunei Darussalam", "Swizerland", "Cyprus", "Czech Republic", "Denmark", "Ecuador", "Eritrea",  "Djibouti", "Spain", "Estonia", "France", "Finland", "Germany", "United Kingdom", "Iceland", "Hungary", "Indonesia", "Italy", "Japan", "Korea, Republic of", "Luxembourg", "Lao PDR", "Lebanon", "Lithuania", "Macao SAR, China", "Mexico", "Malaysia", "New Zealand", "Poland", "West Bank and Gaza", "Qatar", "Romania", "Slobak Republic", "Venezuela, RB", "Uganda", "United States", "Yemen", "Zimbabwe" )) %>%
  mutate(Year = factor(Year),
         Value = round(Value)) 

newggslopegraph(pe_slope, Year, Value, Country) +labs(title="Change in the share of private secondary education, by country, from 2010 to 2019", check_overlap = T)

## 
## Converting 'Year' to an ordered factor

Table 2-1 illustrates that the overall share of private secondary education has continuously remained at slightly below 20%, except the year 2019 when it marked above 22%. It is interesting to observe from Figure 2-3 that around 96% of the secondary education service has been provided by the private sector in Macao, China while it take s up only 1% in Bulgaria and Romania, implying that each country’s approaches to application of the privatization schemes in education enormously vary. Another interesting phenomenon is a stark increase in the share of private sector provision of secondary education from 29% to 75% over the last ten years in the UK.

4. Relationships between the independent variable and dependent variable

Before plotting the relationship between the independent Variable (lp_gdp) and dependent variable (pe_share), and further creating and analzing regression models, all 5 separate data sets introduced in the previous section has to be merged into one. Also the dependent variable will be lagged in an attempt to provide more robust estimates of the effects of the independent variable by overcoming omitted variable bias and accounting for autocorrelation. *After trying several different lag combinations, 3-year lag structure was selected based on Akaike (AIC) and Bayesian (BIC) information criteria.

##merging two main data sets: the main independent variable and dependent variable
dataset_merged1 <- merge(lpdata, pedata, by=c("Country","Year"))
dataset_merged1 <- dataset_merged1 %>% 
  rename(
    lp_gdp = Value.x,
    pe_share = Value.y
    )
##lagging the dependent variable
library(Hmisc)

## Loading required package: lattice

## Loading required package: Formula

## 
## Attaching package: 'Hmisc'

## The following objects are masked from 'package:dplyr':
## 
##     src, summarize

## The following object is masked from 'package:arsenal':
## 
##     %nin%

## The following objects are masked from 'package:base':
## 
##     format.pval, units

dataset_merged1$lp_gdp_lagged <- Lag(dataset_merged1$lp_gdp, -3)
lagged_lpgdp_data <- dplyr::select(dataset_merged1, Country, Year, pe_share, lp_gdp, lp_gdp_lagged)
head(lagged_lpgdp_data, addrownums = FALSE)

##       Country Year pe_share lp_gdp lp_gdp_lagged
## 1 Afghanistan 2010       NA   9573          9943
## 2 Afghanistan 2011  1.27354   9219          9697
## 3 Afghanistan 2012  1.94761   9910          9365
## 4 Afghanistan 2013       NA   9943          9178
## 5 Afghanistan 2014  1.97750   9697          9048
## 6 Afghanistan 2015  2.72148   9365          8871

##further merging the data sets for control variables
dataset_merged2 <- merge(lagged_lpgdp_data, working_hr, by=c("Country","Year"))
dataset_merged2 <- dataset_merged2 %>% 
  rename(
    mwwhour = Value
    )

dataset_merged3 <- merge(dataset_merged2, conpri_health, by=c("Country","Year"))
dataset_merged3 <- dataset_merged3 %>% 
  rename(
    healthconpri = Value
    )

dataset_merged4 <- merge(dataset_merged3, edu_price, by=c("Country","Year"))
dataset_merged4 <- dataset_merged4 %>% 
  rename(
   educost = Value
    )


##filtering years that are lagged
library(dplyr)
data_filtered <- filter(dataset_merged4, Year >=2010 & Year < 2017)

After merging and filtering, countries that are covered in all 5 separate data sets between 2010 and 2016 are left. Through this we obtain a total of 764 observations with 8 variables.

Using this tailored data set, relationship between the independent variables and the dependent variable were plotted below.

plot(lm(data_filtered$lp_gdp_lagged ~ data_filtered$pe_share))

The plot shows that the scatter pattern of the residuals over the range of measured values is clearly unequal, meaning that we can detect heteroskedasticity. The plot also supports the occurrence of heteroskedasticity. I choose not to correct for this heteroskedasticity as it is possible that the variance of the least squares estimator would be not too huge and therefore would not hamper from getting precise estimates, having the large sample size.

5.Regression results for models

First, three regression models (pooled OLS, fixed-effects and random-effects) that do not include control variables were prepared below. While using pooled OLS is often considered problematic in a panel context as it ignores all individually specific effects, it is worth trying to test it here.

ols1 <- lm(lp_gdp_lagged ~ pe_share, data_filtered)
library(sjPlot)

## #refugeeswelcome

tab_model(ols1, digits = 3)
 lp\_gdp\_lagged
PredictorsEstimatesCIp
(Intercept)62060.58956877.492 – 67243.686<0.001
pe\_share-268.902-466.435 – -71.3690.008
Observations591
R2 / R2 adjusted0.012 / 0.010
library(lme4)

## Loading required package: Matrix

fe1 <- lm(lp_gdp_lagged ~ pe_share + factor(Country), data = data_filtered)
tab_model(fe1, digits = 3)
 lp\_gdp\_lagged
PredictorsEstimatesCIp
(Intercept)8610.5364528.714 – 12692.358<0.001
pe\_share108.538-12.435 – 229.5100.079
Country \[Albania\]23028.37117853.127 – 28203.615<0.001
Country \[Angola\]9992.2854068.616 – 15915.9550.001
Country \[Argentina\]41297.86432664.483 – 49931.245<0.001
Country \[Australia\]86073.46178161.640 – 93985.282<0.001
Country \[Austria\]100307.99395367.721 – 105248.265<0.001
Country \[Bahrain\]71696.65966216.419 – 77176.899<0.001
Country \[Bangladesh\]-8819.769-20998.941 – 3359.4030.155
Country \[Barbados\]22832.77417670.906 – 27994.641<0.001
Country \[Belarus\]28194.44523324.007 – 33064.883<0.001
Country \[Belgium\]106331.59998034.816 – 114628.381<0.001
Country \[Belize\]2183.220-6651.399 – 11017.8390.627
Country \[Benin\]-2569.466-7967.415 – 2828.4840.350
Country \[Bhutan\]13112.2437866.012 – 18358.474<0.001
Country \[Bolivia\]7800.3862799.494 – 12801.2770.002
Country \[Bosnia and
Herzegovina\]
34883.29530019.176 – 39747.414<0.001
Country \[Brunei
Darussalam\]
124750.196119535.750 – 129964.642<0.001
Country \[Bulgaria\]38460.51533597.511 – 43323.520<0.001
Country \[Burkina Faso\]-6742.397-14577.661 – 1092.8670.092
Country \[Burundi\]-7650.669-12569.249 – -2732.0900.002
Country \[Cameroon\]-3138.646-9093.953 – 2816.6600.301
Country \[Canada\]85154.47878691.926 – 91617.029<0.001
Country \[Chad\]-5992.857-12607.696 – 621.9830.076
Country \[Chile\]36251.20627760.446 – 44741.966<0.001
Country \[Colombia\]18901.25913573.724 – 24228.794<0.001
Country \[Comoros\]-2055.745-10668.812 – 6557.3230.639
Country \[Costa Rica\]32467.60327538.577 – 37396.629<0.001
Country \[Croatia\]57392.31052528.455 – 62256.166<0.001
Country \[Cyprus\]47546.14142355.844 – 52736.439<0.001
Country \[Denmark\]102857.25997815.685 – 107898.833<0.001
Country \[Djibouti\]3888.911-1550.888 – 9328.7090.161
Country \[Dominican
Republic\]
26968.50221686.794 – 32250.210<0.001
Country \[Ecuador\]13665.9427790.274 – 19541.610<0.001
Country \[El Salvador\]9820.9904666.951 – 14975.028<0.001
Country \[Estonia\]57464.20352599.932 – 62328.474<0.001
Country \[Ethiopia\]-5879.042-11714.890 – -43.1950.048
Country \[Finland\]92806.11687811.072 – 97801.160<0.001
Country \[France\]97143.20791530.068 – 102756.345<0.001
Country \[Georgia\]18753.60513290.767 – 24216.442<0.001
Country \[Germany\]93811.16988889.145 – 98733.192<0.001
Country \[Ghana\]2046.318-3361.476 – 7454.1110.458
Country \[Greece\]76643.06771775.471 – 81510.664<0.001
Country \[Guatemala\]4816.604-3919.750 – 13552.9580.279
Country \[Guinea\]-5336.918-12727.212 – 2053.3750.157
Country \[Honduras\]1316.588-4365.626 – 6998.8030.649
Country \[Hungary\]53496.84348190.244 – 58803.443<0.001
Country \[Iceland\]82933.02577897.094 – 87968.957<0.001
Country \[Ireland\]152939.726147950.715 – 157928.736<0.001
Country \[Israel\]82285.65977308.394 – 87262.924<0.001
Country \[Italy\]100003.82195107.839 – 104899.804<0.001
Country \[Jamaica\]12233.9775800.028 – 18667.925<0.001
Country \[Japan\]67140.71461867.139 – 72414.288<0.001
Country \[Jordan\]35411.07029901.884 – 40920.255<0.001
Country \[Kazakhstan\]41988.05637114.380 – 46861.733<0.001
Country \[Kuwait\]84601.65378187.135 – 91016.171<0.001
Country \[Latvia\]50039.95845176.237 – 54903.679<0.001
Country \[Lebanon\]34898.18326362.051 – 43434.314<0.001
Country \[Lesotho\]-781.296-5766.959 – 4204.3670.758
Country \[Liberia\]-11573.187-20956.579 – -2189.7940.016
Country \[Lithuania\]59693.50354829.760 – 64557.246<0.001
Country \[Luxembourg\]231069.001225863.239 – 236274.762<0.001
Country \[Madagascar\]-9658.019-16412.514 – -2903.5240.005
Country \[Malawi\]-6899.473-12319.588 – -1479.3580.013
Country \[Malaysia\]45184.49740276.454 – 50092.540<0.001
Country \[Mali\]-6179.716-12735.367 – 375.9360.065
Country \[Malta\]79678.12973462.055 – 85894.204<0.001
Country \[Mauritania\]9328.4163652.024 – 15004.8080.001
Country \[Mauritius\]31839.68623576.618 – 40102.755<0.001
Country \[Mexico\]35671.25630639.913 – 40702.599<0.001
Country \[Mongolia\]15744.4747588.970 – 23899.978<0.001
Country \[Mozambique\]-6831.258-11917.421 – -1745.0950.009
Country \[Myanmar\]2147.052-4286.095 – 8580.1980.512
Country \[Netherlands\]99690.18794303.417 – 105076.957<0.001
Country \[New Zealand\]68666.82863692.402 – 73641.255<0.001
Country \[Nicaragua\]1456.702-7003.196 – 9916.6000.735
Country \[Niger\]-7332.067-12811.038 – -1853.0960.009
Country \[Nigeria\]7683.3712339.970 – 13026.7720.005
Country \[North Macedonia\]34763.35929613.049 – 39913.669<0.001
Country \[Norway\]112792.837107896.431 – 117689.243<0.001
Country \[Oman\]46128.92340912.861 – 51344.984<0.001
Country \[Pakistan\]1380.769-4701.592 – 7463.1300.656
Country \[Panama\]53529.36248282.284 – 58776.440<0.001
Country \[Paraguay\]14384.9188541.811 – 20228.026<0.001
Country \[Peru\]10974.4295113.384 – 16835.474<0.001
Country \[Philippines\]10503.6384435.298 – 16571.9780.001
Country \[Poland\]54946.47450037.366 – 59855.582<0.001
Country \[Portugal\]60753.15355605.629 – 65900.677<0.001
Country \[Qatar\]114440.267107569.264 – 121311.269<0.001
Country \[Russian
Federation\]
45308.21840321.175 – 50295.261<0.001
Country \[Rwanda\]-6638.629-11845.494 – -1431.7640.013
Country \[Samoa\]12883.8756597.962 – 19169.788<0.001
Country \[Saudi Arabia\]110441.418103891.828 – 116991.009<0.001
Country \[Senegal\]555.820-7876.283 – 8987.9230.897
Country \[Serbia\]25674.04220803.803 – 30544.280<0.001
Country \[Sierra Leone\]-4268.633-9464.901 – 927.6350.107
Country \[Slovenia\]68659.70163796.377 – 73523.025<0.001
Country \[South Africa\]35186.45630037.174 – 40335.737<0.001
Country \[Spain\]84504.71578776.871 – 90232.560<0.001
Country \[Sudan\]6420.349-236.480 – 13077.1780.059
Country \[Sweden\]95645.24490452.980 – 100837.508<0.001
Country \[Switzerland\]110991.737105917.251 – 116066.222<0.001
Country \[Timor-Leste\]-3106.091-8872.075 – 2659.8920.290
Country \[Togo\]-6941.307-15450.405 – 1567.7920.110
Country \[Tunisia\]25794.20720791.820 – 30796.593<0.001
Country \[Turkey\]69720.93964571.527 – 74870.350<0.001
Country \[United Arab
Emirates\]
82384.58871175.828 – 93593.348<0.001
Country \[United Kingdom\]77307.13069651.981 – 84962.279<0.001
Country \[United States\]114231.963109322.538 – 119141.389<0.001
Country \[Uruguay\]34875.03929746.454 – 40003.624<0.001
Country \[Zimbabwe\]-10463.463-22624.252 – 1697.3250.092
Observations591
R2 / R2 adjusted0.995 / 0.993
library(stargazer)

## 
## Please cite as:

##  Hlavac, Marek (2018). stargazer: Well-Formatted Regression and Summary Statistics Tables.

##  R package version 5.2.2. https://CRAN.R-project.org/package=stargazer

stargazer(ols1, fe1, type="text", title = "Regression Results for Models without Control Variables", column.labels = c("Pooled OLS", "Fixed-Effects"), dep.var.labels=c("Labour Productivity"), align=TRUE)

## 
## Regression Results for Models without Control Variables
## =======================================================================================
##                                                      Dependent variable:               
##                                       -------------------------------------------------
##                                                      Labour Productivity               
##                                             Pooled OLS             Fixed-Effects       
##                                                (1)                      (2)            
## ---------------------------------------------------------------------------------------
## pe_share                                   -268.902***                108.538*         
##                                             (100.577)                 (61.566)         
##                                                                                        
## factor(Country)Albania                                             23,028.370***       
##                                                                     (2,633.821)        
##                                                                                        
## factor(Country)Angola                                               9,992.285***       
##                                                                     (3,014.715)        
##                                                                                        
## factor(Country)Argentina                                           41,297.860***       
##                                                                     (4,393.760)        
##                                                                                        
## factor(Country)Australia                                           86,073.460***       
##                                                                     (4,026.539)        
##                                                                                        
## factor(Country)Austria                                             100,308.000***      
##                                                                     (2,514.238)        
##                                                                                        
## factor(Country)Bahrain                                             71,696.660***       
##                                                                     (2,789.042)        
##                                                                                        
## factor(Country)Bangladesh                                            -8,819.769        
##                                                                     (6,198.309)        
##                                                                                        
## factor(Country)Barbados                                            22,832.770***       
##                                                                     (2,627.014)        
##                                                                                        
## factor(Country)Belarus                                             28,194.440***       
##                                                                     (2,478.697)        
##                                                                                        
## factor(Country)Belgium                                             106,331.600***      
##                                                                     (4,222.456)        
##                                                                                        
## factor(Country)Belize                                                2,183.220         
##                                                                     (4,496.176)        
##                                                                                        
## factor(Country)Benin                                                 -2,569.466        
##                                                                     (2,747.162)        
##                                                                                        
## factor(Country)Bhutan                                              13,112.240***       
##                                                                     (2,669.949)        
##                                                                                        
## factor(Country)Bolivia                                              7,800.386***       
##                                                                     (2,545.089)        
##                                                                                        
## factor(Country)Bosnia and Herzegovina                              34,883.290***       
##                                                                     (2,475.481)        
##                                                                                        
## factor(Country)Brunei Darussalam                                   124,750.200***      
##                                                                     (2,653.772)        
##                                                                                        
## factor(Country)Bulgaria                                            38,460.510***       
##                                                                     (2,474.914)        
##                                                                                        
## factor(Country)Burkina Faso                                         -6,742.397*        
##                                                                     (3,987.577)        
##                                                                                        
## factor(Country)Burundi                                             -7,650.669***       
##                                                                     (2,503.198)        
##                                                                                        
## factor(Country)Cameroon                                              -3,138.646        
##                                                                     (3,030.816)        
##                                                                                        
## factor(Country)Canada                                              85,154.480***       
##                                                                     (3,288.967)        
##                                                                                        
## factor(Country)Chad                                                 -5,992.857*        
##                                                                     (3,366.470)        
##                                                                                        
## factor(Country)Chile                                               36,251.210***       
##                                                                     (4,321.177)        
##                                                                                        
## factor(Country)Colombia                                            18,901.260***       
##                                                                     (2,711.326)        
##                                                                                        
## factor(Country)Comoros                                               -2,055.745        
##                                                                     (4,383.422)        
##                                                                                        
## factor(Country)Costa Rica                                          32,467.600***       
##                                                                     (2,508.514)        
##                                                                                        
## factor(Country)Croatia                                             57,392.310***       
##                                                                     (2,475.347)        
##                                                                                        
## factor(Country)Cyprus                                              47,546.140***       
##                                                                     (2,641.482)        
##                                                                                        
## factor(Country)Denmark                                             102,857.300***      
##                                                                     (2,565.793)        
##                                                                                        
## factor(Country)Djibouti                                              3,888.911         
##                                                                     (2,768.460)        
##                                                                                        
## factor(Country)Dominican Republic                                  26,968.500***       
##                                                                     (2,688.004)        
##                                                                                        
## factor(Country)Ecuador                                             13,665.940***       
##                                                                     (2,990.286)        
##                                                                                        
## factor(Country)El Salvador                                          9,820.990***       
##                                                                     (2,623.029)        
##                                                                                        
## factor(Country)Estonia                                             57,464.200***       
##                                                                     (2,475.559)        
##                                                                                        
## factor(Country)Ethiopia                                             -5,879.042**       
##                                                                     (2,970.020)        
##                                                                                        
## factor(Country)Finland                                             92,806.120***       
##                                                                     (2,542.112)        
##                                                                                        
## factor(Country)France                                              97,143.210***       
##                                                                     (2,856.677)        
##                                                                                        
## factor(Country)Georgia                                             18,753.600***       
##                                                                     (2,780.186)        
##                                                                                        
## factor(Country)Germany                                             93,811.170***       
##                                                                     (2,504.950)        
##                                                                                        
## factor(Country)Ghana                                                 2,046.318         
##                                                                     (2,752.172)        
##                                                                                        
## factor(Country)Greece                                              76,643.070***       
##                                                                     (2,477.251)        
##                                                                                        
## factor(Country)Guatemala                                             4,816.604         
##                                                                     (4,446.166)        
##                                                                                        
## factor(Country)Guinea                                                -5,336.918        
##                                                                     (3,761.120)        
##                                                                                        
## factor(Country)Honduras                                              1,316.588         
##                                                                     (2,891.832)        
##                                                                                        
## factor(Country)Hungary                                             53,496.840***       
##                                                                     (2,700.672)        
##                                                                                        
## factor(Country)Iceland                                             82,933.020***       
##                                                                     (2,562.921)        
##                                                                                        
## factor(Country)Ireland                                             152,939.700***      
##                                                                     (2,539.042)        
##                                                                                        
## factor(Country)Israel                                              82,285.660***       
##                                                                     (2,533.064)        
##                                                                                        
## factor(Country)Italy                                               100,003.800***      
##                                                                     (2,491.698)        
##                                                                                        
## factor(Country)Jamaica                                             12,233.980***       
##                                                                     (3,274.410)        
##                                                                                        
## factor(Country)Japan                                               67,140.710***       
##                                                                     (2,683.864)        
##                                                                                        
## factor(Country)Jordan                                              35,411.070***       
##                                                                     (2,803.773)        
##                                                                                        
## factor(Country)Kazakhstan                                          41,988.060***       
##                                                                     (2,480.345)        
##                                                                                        
## factor(Country)Kuwait                                              84,601.650***       
##                                                                     (3,264.521)        
##                                                                                        
## factor(Country)Latvia                                              50,039.960***       
##                                                                     (2,475.279)        
##                                                                                        
## factor(Country)Lebanon                                             34,898.180***       
##                                                                     (4,344.267)        
##                                                                                        
## factor(Country)Lesotho                                                -781.296         
##                                                                     (2,537.338)        
##                                                                                        
## factor(Country)Liberia                                             -11,573.190**       
##                                                                     (4,775.462)        
##                                                                                        
## factor(Country)Lithuania                                           59,693.500***       
##                                                                     (2,475.290)        
##                                                                                        
## factor(Country)Luxembourg                                          231,069.000***      
##                                                                     (2,649.352)        
##                                                                                        
## factor(Country)Madagascar                                          -9,658.019***       
##                                                                     (3,437.545)        
##                                                                                        
## factor(Country)Malawi                                               -6,899.473**       
##                                                                     (2,758.443)        
##                                                                                        
## factor(Country)Malaysia                                            45,184.500***       
##                                                                     (2,497.836)        
##                                                                                        
## factor(Country)Mali                                                 -6,179.716*        
##                                                                     (3,336.348)        
##                                                                                        
## factor(Country)Malta                                               79,678.130***       
##                                                                     (3,163.528)        
##                                                                                        
## factor(Country)Mauritania                                           9,328.416***       
##                                                                     (2,888.869)        
##                                                                                        
## factor(Country)Mauritius                                           31,839.690***       
##                                                                     (4,205.298)        
##                                                                                        
## factor(Country)Mexico                                              35,671.260***       
##                                                                     (2,560.586)        
##                                                                                        
## factor(Country)Mongolia                                            15,744.470***       
##                                                                     (4,150.556)        
##                                                                                        
## factor(Country)Mozambique                                          -6,831.258***       
##                                                                     (2,588.485)        
##                                                                                        
## factor(Country)Myanmar                                               2,147.052         
##                                                                     (3,274.002)        
##                                                                                        
## factor(Country)Netherlands                                         99,690.190***       
##                                                                     (2,741.472)        
##                                                                                        
## factor(Country)New Zealand                                         68,666.830***       
##                                                                     (2,531.620)        
##                                                                                        
## factor(Country)Nicaragua                                             1,456.702         
##                                                                     (4,305.470)        
##                                                                                        
## factor(Country)Niger                                               -7,332.067***       
##                                                                     (2,788.396)        
##                                                                                        
## factor(Country)Nigeria                                              7,683.371***       
##                                                                     (2,719.401)        
##                                                                                        
## factor(Country)North Macedonia                                     34,763.360***       
##                                                                     (2,621.132)        
##                                                                                        
## factor(Country)Norway                                              112,792.800***      
##                                                                     (2,491.913)        
##                                                                                        
## factor(Country)Oman                                                46,128.920***       
##                                                                     (2,654.594)        
##                                                                                        
## factor(Country)Pakistan                                              1,380.769         
##                                                                     (3,095.477)        
##                                                                                        
## factor(Country)Panama                                              53,529.360***       
##                                                                     (2,670.379)        
##                                                                                        
## factor(Country)Paraguay                                            14,384.920***       
##                                                                     (2,973.715)        
##                                                                                        
## factor(Country)Peru                                                10,974.430***       
##                                                                     (2,982.844)        
##                                                                                        
## factor(Country)Philippines                                         10,503.640***       
##                                                                     (3,088.342)        
##                                                                                        
## factor(Country)Poland                                              54,946.470***       
##                                                                     (2,498.377)        
##                                                                                        
## factor(Country)Portugal                                            60,753.150***       
##                                                                     (2,619.714)        
##                                                                                        
## factor(Country)Qatar                                               114,440.300***      
##                                                                     (3,496.838)        
##                                                                                        
## factor(Country)Russian Federation                                  45,308.220***       
##                                                                     (2,538.041)        
##                                                                                        
## factor(Country)Rwanda                                               -6,638.629**       
##                                                                     (2,649.914)        
##                                                                                        
## factor(Country)Samoa                                               12,883.880***       
##                                                                     (3,199.071)        
##                                                                                        
## factor(Country)Saudi Arabia                                        110,441.400***      
##                                                                     (3,333.263)        
##                                                                                        
## factor(Country)Senegal                                                555.820          
##                                                                     (4,291.324)        
##                                                                                        
## factor(Country)Serbia                                              25,674.040***       
##                                                                     (2,478.596)        
##                                                                                        
## factor(Country)Sierra Leone                                          -4,268.633        
##                                                                     (2,644.521)        
##                                                                                        
## factor(Country)Slovenia                                            68,659.700***       
##                                                                     (2,475.077)        
##                                                                                        
## factor(Country)South Africa                                        35,186.460***       
##                                                                     (2,620.608)        
##                                                                                        
## factor(Country)Spain                                               84,504.710***       
##                                                                     (2,915.054)        
##                                                                                        
## factor(Country)Sudan                                                 6,420.349*        
##                                                                     (3,387.840)        
##                                                                                        
## factor(Country)Sweden                                              95,645.240***       
##                                                                     (2,642.483)        
##                                                                                        
## factor(Country)Switzerland                                         110,991.700***      
##                                                                     (2,582.543)        
##                                                                                        
## factor(Country)Timor-Leste                                           -3,106.091        
##                                                                     (2,934.465)        
##                                                                                        
## factor(Country)Togo                                                  -6,941.307        
##                                                                     (4,330.510)        
##                                                                                        
## factor(Country)Tunisia                                             25,794.210***       
##                                                                     (2,545.849)        
##                                                                                        
## factor(Country)Turkey                                              69,720.940***       
##                                                                     (2,620.674)        
##                                                                                        
## factor(Country)United Arab Emirates                                82,384.590***       
##                                                                     (5,704.440)        
##                                                                                        
## factor(Country)United Kingdom                                      77,307.130***       
##                                                                     (3,895.912)        
##                                                                                        
## factor(Country)United States                                       114,232.000***      
##                                                                     (2,498.539)        
##                                                                                        
## factor(Country)Uruguay                                             34,875.040***       
##                                                                     (2,610.075)        
##                                                                                        
## factor(Country)Zimbabwe                                             -10,463.460*       
##                                                                     (6,188.953)        
##                                                                                        
## Constant                                  62,060.590***             8,610.536***       
##                                            (2,639.052)              (2,077.349)        
##                                                                                        
## ---------------------------------------------------------------------------------------
## Observations                                   591                      591            
## R2                                            0.012                    0.995           
## Adjusted R2                                   0.010                    0.993           
## Residual Std. Error                   43,964.570 (df = 589)     3,586.478 (df = 480)   
## F Statistic                           7.148*** (df = 1; 589) 810.024*** (df = 110; 480)
## =======================================================================================
## Note:                                                       *p<0.1; **p<0.05; ***p<0.01

<Pooled OLS, Fixed-Effects, and Random-Effects>

library(plm)

## 
## Attaching package: 'plm'

## The following objects are masked from 'package:dplyr':
## 
##     between, lag, lead

pooledols1 <- plm(lp_gdp_lagged ~ pe_share, data=data_filtered, model = "pooling", index = c("Country", "Year"))
fixeff1 <- plm(lp_gdp_lagged ~ pe_share, data=data_filtered, model = "within", index = c("Country", "Year"))
randeff1 <- plm(lp_gdp_lagged ~ pe_share, data=data_filtered, model = "random", index = c("Country", "Year"))

library(stargazer)
stargazer(pooledols1, fixeff1, randeff1, type="text", title = "Regression Results for Models without Control Variables", column.labels = c("Pooled OLS", "Fixed-Effects", "Random-Effects") ,dep.var.labels=c("Labour Productivity"), align=TRUE)

## 
## Regression Results for Models without Control Variables
## =======================================================================
##                                 Dependent variable:                    
##              ----------------------------------------------------------
##                                 Labour Productivity                    
##                    Pooled OLS          Fixed-Effects     Random-Effects
##                       (1)                   (2)               (3)      
## -----------------------------------------------------------------------
## pe_share          -268.902***             108.538*           82.469    
##                    (100.577)              (61.566)          (59.395)   
##                                                                        
## Constant         62,060.590***                           49,722.330*** 
##                   (2,639.052)                             (4,380.876)  
##                                                                        
## -----------------------------------------------------------------------
## Observations          591                   591               591      
## R2                   0.012                 0.006             0.0001    
## Adjusted R2          0.010                 -0.221            -0.002    
## F Statistic  7.148*** (df = 1; 589) 3.108* (df = 1; 480)     1.928     
## =======================================================================
## Note:                                       *p<0.1; **p<0.05; ***p<0.01

The first regression results for models without control variables do not allow us to observe any statistically significant correlation between the share of private education and the level of productivity. Pooled OLS model shows that the share of private education (pe-share) is statistically significant at 95% confidence level, while it is statistically significant at 90% confidence level for the Fixed=Effects Model. However, the fact that: i) R-square value and adjusted R-square value are extremely low and even negative for the Fixed-Effects model and the Random-effects model; and ii) the overall significance of the model presented by F-statistic is low, suggests that the models hardly explains the variation in the dependent variable. These results let us conclude that none of the above models without control variable are a good fit.

It is followed by three additional regression models with three control variables included.

ols2 <- lm(lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost, data_filtered)
tab_model(ols2, digits = 3)
 lp\_gdp\_lagged
PredictorsEstimatesCIp
(Intercept)58105.62848943.016 – 67268.240<0.001
pe\_share42.417-190.712 – 275.5460.721
mwwhour0.0050.000 – 0.0090.033
healthconpri2497.4641041.250 – 3953.6770.001
educost-5307.204-7392.403 – -3222.004<0.001
Observations577
R2 / R2 adjusted0.072 / 0.065
library(lme4)
fe2 <- lm(lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost + factor(Country), data = data_filtered)
tab_model(fe2, digits = 3)
 lp\_gdp\_lagged
PredictorsEstimatesCIp
(Intercept)5363.991-866.914 – 11594.8970.091
pe\_share34.048-86.172 – 154.2690.578
mwwhour0.008-0.001 – 0.0170.072
healthconpri120.235-685.591 – 926.0610.769
educost798.586-101.767 – 1698.9380.082
Country \[Albania\]24923.50819050.324 – 30796.691<0.001
Country \[Angola\]9050.1572774.905 – 15325.4080.005
Country \[Argentina\]37757.62428598.115 – 46917.132<0.001
Country \[Australia\]85252.00077123.113 – 93380.887<0.001
Country \[Austria\]101494.69296407.363 – 106582.021<0.001
Country \[Bahrain\]71637.80063522.695 – 79752.906<0.001
Country \[Barbados\]25639.56119614.191 – 31664.930<0.001
Country \[Belarus\]28670.63023368.055 – 33973.205<0.001
Country \[Belgium\]111591.049103026.494 – 120155.604<0.001
Country \[Belize\]6984.313-2887.241 – 16855.8680.165
Country \[Benin\]-3694.976-10928.874 – 3538.9220.316
Country \[Bhutan\]15204.0849300.053 – 21108.114<0.001
Country \[Bolivia\]6269.437-769.412 – 13308.2850.081
Country \[Bosnia and
Herzegovina\]
36752.17731477.410 – 42026.944<0.001
Country \[Brunei
Darussalam\]
125003.698116687.784 – 133319.611<0.001
Country \[Bulgaria\]39712.30734634.523 – 44790.091<0.001
Country \[Burkina Faso\]-4467.078-12765.905 – 3831.7480.291
Country \[Burundi\]-6090.063-11927.671 – -252.4560.041
Country \[Cameroon\]-3855.513-10119.434 – 2408.4070.227
Country \[Canada\]81723.43074259.879 – 89186.982<0.001
Country \[Chad\]-4227.747-11424.448 – 2968.9540.249
Country \[Chile\]35280.18125332.544 – 45227.818<0.001
Country \[Colombia\]12061.5732985.644 – 21137.5010.009
Country \[Comoros\]1307.206-9298.245 – 11912.6580.809
Country \[Costa Rica\]30291.52622987.974 – 37595.078<0.001
Country \[Croatia\]59160.41253686.265 – 64634.558<0.001
Country \[Cyprus\]48329.06942001.171 – 54656.968<0.001
Country \[Denmark\]105366.53799666.942 – 111066.132<0.001
Country \[Djibouti\]6240.934-547.193 – 13029.0610.071
Country \[Dominican
Republic\]
27260.50421336.198 – 33184.810<0.001
Country \[Ecuador\]11963.3695081.364 – 18845.3750.001
Country \[El Salvador\]10155.8284207.354 – 16104.3020.001
Country \[Estonia\]59056.64653542.502 – 64570.790<0.001
Country \[Ethiopia\]-12113.382-22425.862 – -1800.9020.021
Country \[Finland\]95249.03789989.372 – 100508.702<0.001
Country \[France\]92982.51284343.982 – 101621.041<0.001
Country \[Georgia\]17010.5289698.172 – 24322.885<0.001
Country \[Germany\]84992.16774080.181 – 95904.154<0.001
Country \[Ghana\]-432.662-7309.873 – 6444.5480.902
Country \[Greece\]75651.03670179.955 – 81122.116<0.001
Country \[Guatemala\]7127.486-2123.631 – 16378.6030.131
Country \[Guinea\]-2438.663-11164.637 – 6287.3120.583
Country \[Honduras\]2636.800-3964.005 – 9237.6050.433
Country \[Hungary\]55056.92749548.340 – 60565.514<0.001
Country \[Iceland\]85811.42779982.899 – 91639.954<0.001
Country \[Ireland\]153339.779147441.949 – 159237.610<0.001
Country \[Israel\]80474.24573187.541 – 87760.949<0.001
Country \[Italy\]95276.34888468.938 – 102083.759<0.001
Country \[Jamaica\]13084.7846031.233 – 20138.336<0.001
Country \[Japan\]47915.09627785.833 – 68044.360<0.001
Country \[Jordan\]34800.03626643.485 – 42956.587<0.001
Country \[Kazakhstan\]40488.28334933.592 – 46042.974<0.001
Country \[Kuwait\]87118.57179064.644 – 95172.497<0.001
Country \[Latvia\]51235.51345885.768 – 56585.258<0.001
Country \[Lebanon\]35502.17425205.511 – 45798.837<0.001
Country \[Lesotho\]-256.599-7022.146 – 6508.9480.941
Country \[Liberia\]-7614.036-17711.874 – 2483.8010.139
Country \[Lithuania\]60504.72555136.404 – 65873.046<0.001
Country \[Luxembourg\]234259.643227886.463 – 240632.823<0.001
Country \[Madagascar\]-9960.912-17914.893 – -2006.9310.014
Country \[Malawi\]-8762.485-16369.562 – -1155.4070.024
Country \[Malaysia\]43008.41536732.810 – 49284.020<0.001
Country \[Mali\]-3903.092-11032.904 – 3226.7200.283
Country \[Mauritania\]12900.8926159.624 – 19642.159<0.001
Country \[Mauritius\]35827.24826235.714 – 45418.781<0.001
Country \[Mexico\]18501.3821401.827 – 35600.9370.034
Country \[Mongolia\]14926.5915584.830 – 24268.3510.002
Country \[Mozambique\]-6726.619-12842.055 – -611.1840.031
Country \[Myanmar\]-6140.434-16789.028 – 4508.1610.258
Country \[Netherlands\]100247.24994331.716 – 106162.782<0.001
Country \[New Zealand\]70035.75264581.806 – 75489.698<0.001
Country \[Nicaragua\]965.703-8468.747 – 10400.1530.841
Country \[Niger\]-6449.584-12477.480 – -421.6880.036
Country \[Nigeria\]-8889.916-26578.390 – 8798.5570.324
Country \[North Macedonia\]36532.19730760.801 – 42303.593<0.001
Country \[Norway\]115220.973109764.704 – 120677.242<0.001
Country \[Oman\]48148.96541589.316 – 54708.615<0.001
Country \[Pakistan\]-19606.527-42924.280 – 3711.2270.099
Country \[Panama\]55126.40548928.981 – 61323.829<0.001
Country \[Paraguay\]14513.4147535.571 – 21491.257<0.001
Country \[Peru\]3715.834-6535.198 – 13966.8660.477
Country \[Philippines\]-1593.513-15165.932 – 11978.9060.818
Country \[Poland\]51855.84146131.650 – 57580.031<0.001
Country \[Portugal\]61371.60255950.428 – 66792.775<0.001
Country \[Qatar\]115370.890105803.077 – 124938.702<0.001
Country \[Russian
Federation\]
24999.5193047.750 – 46951.2870.026
Country \[Rwanda\]-5440.572-12487.044 – 1605.9010.130
Country \[Samoa\]16910.6878574.265 – 25247.110<0.001
Country \[Saudi Arabia\]106514.37298404.783 – 114623.961<0.001
Country \[Senegal\]1848.066-6976.455 – 10672.5860.681
Country \[Serbia\]26346.67921329.200 – 31364.159<0.001
Country \[Sierra Leone\]-4800.947-11969.068 – 2367.1730.189
Country \[Slovenia\]70163.11264833.683 – 75492.541<0.001
Country \[South Africa\]31475.99324459.787 – 38492.198<0.001
Country \[Spain\]82748.56976120.941 – 89376.198<0.001
Country \[Sudan\]6166.548-1543.996 – 13877.0910.117
Country \[Sweden\]98078.35492636.571 – 103520.138<0.001
Country \[Switzerland\]111389.004102297.785 – 120480.224<0.001
Country \[Timor-Leste\]-126.318-7936.917 – 7684.2800.975
Country \[Togo\]-4674.483-13514.625 – 4165.6590.299
Country \[Tunisia\]25174.20619537.983 – 30810.429<0.001
Country \[Turkey\]61291.53251303.173 – 71279.892<0.001
Country \[United Arab
Emirates\]
81522.28667938.454 – 95106.117<0.001
Country \[United Kingdom\]73884.43063628.256 – 84140.604<0.001
Country \[United States\]71578.30026716.567 – 116440.0330.002
Country \[Uruguay\]35179.16529111.689 – 41246.640<0.001
Country \[Zimbabwe\]-5116.328-18169.033 – 7936.3770.442
Observations577
R2 / R2 adjusted0.995 / 0.994
stargazer(ols2, fe2, type="text", title = "Regression Results for Models without Control Variables", column.labels = c("Pooled OLS", "Fixed-Effects"), dep.var.labels=c("Labour Productivity"), align=TRUE)

## 
## Regression Results for Models without Control Variables
## ========================================================================================
##                                                      Dependent variable:                
##                                       --------------------------------------------------
##                                                      Labour Productivity                
##                                             Pooled OLS              Fixed-Effects       
##                                                 (1)                      (2)            
## ----------------------------------------------------------------------------------------
## pe_share                                      42.417                    34.048          
##                                              (118.694)                 (61.178)         
##                                                                                         
## mwwhour                                       0.005**                   0.008*          
##                                               (0.002)                  (0.004)          
##                                                                                         
## healthconpri                               2,497.464***                120.235          
##                                              (741.408)                (410.073)         
##                                                                                         
## educost                                    -5,307.204***               798.586*         
##                                             (1,061.646)               (458.176)         
##                                                                                         
## factor(Country)Albania                                              24,923.510***       
##                                                                      (2,988.778)        
##                                                                                         
## factor(Country)Angola                                                9,050.157***       
##                                                                      (3,193.384)        
##                                                                                         
## factor(Country)Argentina                                            37,757.620***       
##                                                                      (4,661.141)        
##                                                                                         
## factor(Country)Australia                                            85,252.000***       
##                                                                      (4,136.672)        
##                                                                                         
## factor(Country)Austria                                              101,494.700***      
##                                                                      (2,588.868)        
##                                                                                         
## factor(Country)Bahrain                                              71,637.800***       
##                                                                      (4,129.659)        
##                                                                                         
## factor(Country)Barbados                                             25,639.560***       
##                                                                      (3,066.223)        
##                                                                                         
## factor(Country)Belarus                                              28,670.630***       
##                                                                      (2,698.403)        
##                                                                                         
## factor(Country)Belgium                                              111,591.000***      
##                                                                      (4,358.378)        
##                                                                                         
## factor(Country)Belize                                                 6,984.313         
##                                                                      (5,023.491)        
##                                                                                         
## factor(Country)Benin                                                  -3,694.976        
##                                                                      (3,681.226)        
##                                                                                         
## factor(Country)Bhutan                                               15,204.080***       
##                                                                      (3,004.475)        
##                                                                                         
## factor(Country)Bolivia                                                6,269.437*        
##                                                                      (3,581.968)        
##                                                                                         
## factor(Country)Bosnia and Herzegovina                               36,752.180***       
##                                                                      (2,684.252)        
##                                                                                         
## factor(Country)Brunei Darussalam                                    125,003.700***      
##                                                                      (4,231.848)        
##                                                                                         
## factor(Country)Bulgaria                                             39,712.310***       
##                                                                      (2,584.011)        
##                                                                                         
## factor(Country)Burkina Faso                                           -4,467.078        
##                                                                      (4,223.152)        
##                                                                                         
## factor(Country)Burundi                                               -6,090.063**       
##                                                                      (2,970.673)        
##                                                                                         
## factor(Country)Cameroon                                               -3,855.513        
##                                                                      (3,187.618)        
##                                                                                         
## factor(Country)Canada                                               81,723.430***       
##                                                                      (3,798.093)        
##                                                                                         
## factor(Country)Chad                                                   -4,227.747        
##                                                                      (3,662.297)        
##                                                                                         
## factor(Country)Chile                                                35,280.180***       
##                                                                      (5,062.208)        
##                                                                                         
## factor(Country)Colombia                                             12,061.570***       
##                                                                      (4,618.608)        
##                                                                                         
## factor(Country)Comoros                                                1,307.206         
##                                                                      (5,396.960)        
##                                                                                         
## factor(Country)Costa Rica                                           30,291.530***       
##                                                                      (3,716.671)        
##                                                                                         
## factor(Country)Croatia                                              59,160.410***       
##                                                                      (2,785.713)        
##                                                                                         
## factor(Country)Cyprus                                               48,329.070***       
##                                                                      (3,220.176)        
##                                                                                         
## factor(Country)Denmark                                              105,366.500***      
##                                                                      (2,900.441)        
##                                                                                         
## factor(Country)Djibouti                                               6,240.934*        
##                                                                      (3,454.379)        
##                                                                                         
## factor(Country)Dominican Republic                                   27,260.500***       
##                                                                      (3,014.793)        
##                                                                                         
## factor(Country)Ecuador                                              11,963.370***       
##                                                                      (3,502.153)        
##                                                                                         
## factor(Country)El Salvador                                          10,155.830***       
##                                                                      (3,027.092)        
##                                                                                         
## factor(Country)Estonia                                              59,056.650***       
##                                                                      (2,806.068)        
##                                                                                         
## factor(Country)Ethiopia                                             -12,113.380**       
##                                                                      (5,247.871)        
##                                                                                         
## factor(Country)Finland                                              95,249.040***       
##                                                                      (2,676.567)        
##                                                                                         
## factor(Country)France                                               92,982.510***       
##                                                                      (4,396.022)        
##                                                                                         
## factor(Country)Georgia                                              17,010.530***       
##                                                                      (3,721.152)        
##                                                                                         
## factor(Country)Germany                                              84,992.170***       
##                                                                      (5,552.951)        
##                                                                                         
## factor(Country)Ghana                                                   -432.662         
##                                                                      (3,499.712)        
##                                                                                         
## factor(Country)Greece                                               75,651.040***       
##                                                                      (2,784.153)        
##                                                                                         
## factor(Country)Guatemala                                              7,127.486         
##                                                                      (4,707.759)        
##                                                                                         
## factor(Country)Guinea                                                 -2,438.663        
##                                                                      (4,440.522)        
##                                                                                         
## factor(Country)Honduras                                               2,636.800         
##                                                                      (3,359.054)        
##                                                                                         
## factor(Country)Hungary                                              55,056.930***       
##                                                                      (2,803.240)        
##                                                                                         
## factor(Country)Iceland                                              85,811.430***       
##                                                                      (2,966.053)        
##                                                                                         
## factor(Country)Ireland                                              153,339.800***      
##                                                                      (3,001.320)        
##                                                                                         
## factor(Country)Israel                                               80,474.240***       
##                                                                      (3,708.098)        
##                                                                                         
## factor(Country)Italy                                                95,276.350***       
##                                                                      (3,464.192)        
##                                                                                         
## factor(Country)Jamaica                                              13,084.780***       
##                                                                      (3,589.450)        
##                                                                                         
## factor(Country)Japan                                                47,915.100***       
##                                                                      (10,243.490)       
##                                                                                         
## factor(Country)Jordan                                               34,800.040***       
##                                                                      (4,150.750)        
##                                                                                         
## factor(Country)Kazakhstan                                           40,488.280***       
##                                                                      (2,826.702)        
##                                                                                         
## factor(Country)Kuwait                                               87,118.570***       
##                                                                      (4,098.526)        
##                                                                                         
## factor(Country)Latvia                                               51,235.510***       
##                                                                      (2,722.408)        
##                                                                                         
## factor(Country)Lebanon                                              35,502.170***       
##                                                                      (5,239.822)        
##                                                                                         
## factor(Country)Lesotho                                                 -256.599         
##                                                                      (3,442.889)        
##                                                                                         
## factor(Country)Liberia                                                -7,614.036        
##                                                                      (5,138.643)        
##                                                                                         
## factor(Country)Lithuania                                            60,504.720***       
##                                                                      (2,731.861)        
##                                                                                         
## factor(Country)Luxembourg                                           234,259.600***      
##                                                                      (3,243.218)        
##                                                                                         
## factor(Country)Madagascar                                            -9,960.912**       
##                                                                      (4,047.665)        
##                                                                                         
## factor(Country)Malawi                                                -8,762.485**       
##                                                                      (3,871.131)        
##                                                                                         
## factor(Country)Malaysia                                             43,008.420***       
##                                                                      (3,193.564)        
##                                                                                         
## factor(Country)Mali                                                   -3,903.092        
##                                                                      (3,628.258)        
##                                                                                         
## factor(Country)Mauritania                                           12,900.890***       
##                                                                      (3,430.533)        
##                                                                                         
## factor(Country)Mauritius                                            35,827.250***       
##                                                                      (4,880.992)        
##                                                                                         
## factor(Country)Mexico                                                18,501.380**       
##                                                                      (8,701.715)        
##                                                                                         
## factor(Country)Mongolia                                             14,926.590***       
##                                                                      (4,753.886)        
##                                                                                         
## factor(Country)Mozambique                                            -6,726.619**       
##                                                                      (3,112.056)        
##                                                                                         
## factor(Country)Myanmar                                                -6,140.434        
##                                                                      (5,418.915)        
##                                                                                         
## factor(Country)Netherlands                                          100,247.200***      
##                                                                      (3,010.329)        
##                                                                                         
## factor(Country)New Zealand                                          70,035.750***       
##                                                                      (2,775.434)        
##                                                                                         
## factor(Country)Nicaragua                                               965.703          
##                                                                      (4,801.055)        
##                                                                                         
## factor(Country)Niger                                                 -6,449.584**       
##                                                                      (3,067.508)        
##                                                                                         
## factor(Country)Nigeria                                                -8,889.916        
##                                                                      (9,001.407)        
##                                                                                         
## factor(Country)North Macedonia                                      36,532.200***       
##                                                                      (2,936.979)        
##                                                                                         
## factor(Country)Norway                                               115,221.000***      
##                                                                      (2,776.616)        
##                                                                                         
## factor(Country)Oman                                                 48,148.960***       
##                                                                      (3,338.110)        
##                                                                                         
## factor(Country)Pakistan                                              -19,606.530*       
##                                                                      (11,866.070)       
##                                                                                         
## factor(Country)Panama                                               55,126.400***       
##                                                                      (3,153.779)        
##                                                                                         
## factor(Country)Paraguay                                             14,513.410***       
##                                                                      (3,550.923)        
##                                                                                         
## factor(Country)Peru                                                   3,715.834         
##                                                                      (5,216.601)        
##                                                                                         
## factor(Country)Philippines                                            -1,593.513        
##                                                                      (6,906.807)        
##                                                                                         
## factor(Country)Poland                                               51,855.840***       
##                                                                      (2,912.957)        
##                                                                                         
## factor(Country)Portugal                                             61,371.600***       
##                                                                      (2,758.756)        
##                                                                                         
## factor(Country)Qatar                                                115,370.900***      
##                                                                      (4,868.921)        
##                                                                                         
## factor(Country)Russian Federation                                    24,999.520**       
##                                                                      (11,170.940)       
##                                                                                         
## factor(Country)Rwanda                                                 -5,440.572        
##                                                                      (3,585.847)        
##                                                                                         
## factor(Country)Samoa                                                16,910.690***       
##                                                                      (4,242.284)        
##                                                                                         
## factor(Country)Saudi Arabia                                         106,514.400***      
##                                                                      (4,126.852)        
##                                                                                         
## factor(Country)Senegal                                                1,848.066         
##                                                                      (4,490.670)        
##                                                                                         
## factor(Country)Serbia                                               26,346.680***       
##                                                                      (2,553.322)        
##                                                                                         
## factor(Country)Sierra Leone                                           -4,800.947        
##                                                                      (3,647.752)        
##                                                                                         
## factor(Country)Slovenia                                             70,163.110***       
##                                                                      (2,712.069)        
##                                                                                         
## factor(Country)South Africa                                         31,475.990***       
##                                                                      (3,570.445)        
##                                                                                         
## factor(Country)Spain                                                82,748.570***       
##                                                                      (3,372.704)        
##                                                                                         
## factor(Country)Sudan                                                  6,166.548         
##                                                                      (3,923.783)        
##                                                                                         
## factor(Country)Sweden                                               98,078.350***       
##                                                                      (2,769.245)        
##                                                                                         
## factor(Country)Switzerland                                          111,389.000***      
##                                                                      (4,626.390)        
##                                                                                         
## factor(Country)Timor-Leste                                             -126.318         
##                                                                      (3,974.700)        
##                                                                                         
## factor(Country)Togo                                                   -4,674.483        
##                                                                      (4,498.620)        
##                                                                                         
## factor(Country)Tunisia                                              25,174.210***       
##                                                                      (2,868.192)        
##                                                                                         
## factor(Country)Turkey                                               61,291.530***       
##                                                                      (5,082.931)        
##                                                                                         
## factor(Country)United Arab Emirates                                 81,522.290***       
##                                                                      (6,912.615)        
##                                                                                         
## factor(Country)United Kingdom                                       73,884.430***       
##                                                                      (5,219.218)        
##                                                                                         
## factor(Country)United States                                        71,578.300***       
##                                                                      (22,829.480)       
##                                                                                         
## factor(Country)Uruguay                                              35,179.170***       
##                                                                      (3,087.650)        
##                                                                                         
## factor(Country)Zimbabwe                                               -5,116.328        
##                                                                      (6,642.332)        
##                                                                                         
## Constant                                   58,105.630***              5,363.991*        
##                                             (4,664.996)              (3,170.817)        
##                                                                                         
## ----------------------------------------------------------------------------------------
## Observations                                    577                      577            
## R2                                             0.072                    0.995           
## Adjusted R2                                    0.065                    0.994           
## Residual Std. Error                    42,763.310 (df = 572)     3,466.238 (df = 465)   
## F Statistic                           11.076*** (df = 4; 572) 840.889*** (df = 111; 465)
## ========================================================================================
## Note:                                                        *p<0.1; **p<0.05; ***p<0.01

<Pooled OLS, Fixed-Effects, and Random-Effects>

pooledols2 <- plm(lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost, data=data_filtered, model = "pooling", index = c("Country", "Year"))
fixeff2 <- plm(lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost, data=data_filtered, model = "within", index = c("Country", "Year"))
randeff2 <- plm(lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost, data=data_filtered, model = "random", index = c("Country", "Year"))

stargazer(pooledols2, fixeff2, randeff2, type="text", title = "Regression Results for Models with Control Variables", column.labels = c("Pooled OLS", "Fixed-Effects", "Random-Effects") ,dep.var.labels=c("Labour Productivity"), align=TRUE)

## 
## Regression Results for Models with Control Variables
## ========================================================================
##                                  Dependent variable:                    
##              -----------------------------------------------------------
##                                  Labour Productivity                    
##                    Pooled OLS           Fixed-Effects     Random-Effects
##                        (1)                   (2)               (3)      
## ------------------------------------------------------------------------
## pe_share             42.417                 34.048            19.193    
##                     (118.694)              (61.178)          (59.086)   
##                                                                         
## mwwhour              0.005**                0.008*           0.007**    
##                      (0.002)               (0.004)           (0.003)    
##                                                                         
## healthconpri      2,497.464***             120.235           294.378    
##                     (741.408)             (410.073)         (398.051)   
##                                                                         
## educost           -5,307.204***            798.586*          610.373    
##                    (1,061.646)            (458.176)         (449.341)   
##                                                                         
## Constant          58,105.630***                           45,259.910*** 
##                    (4,664.996)                             (4,797.314)  
##                                                                         
## ------------------------------------------------------------------------
## Observations           577                   577               577      
## R2                    0.072                 0.018             0.005     
## Adjusted R2           0.065                 -0.217            -0.002    
## F Statistic  11.076*** (df = 4; 572) 2.090* (df = 4; 465)     8.155*    
## ========================================================================
## Note:                                        *p<0.1; **p<0.05; ***p<0.01

Above all, after including control variables, the most notable problem detected is that the coefficient for the independent variable of interest “pe_share” changes drastically for all three models of Pooled OLS, Fixed-Effects, and Random-Effects. Also none of the above models show any statistically significant sign of correlations between the independent variable of main interest and dependent variable, while mean weekly working hours (mwwhour), consumer price for health services (healthconpri), and cost for educational services (educost) are statistically significant at 95% and 99% confidence level for Pooled OLS, and mean weekly working hours (mwwhour) is statistically significant at 90% and 95% confidence level, respectively, for Fixed-Effects model and Random-Effects model. Consistently low R-square value and adjusted R-square value across the regression models as well as F-statistic value also lead us to confirm that there is no statistically significant correlation that we can observed to prove the hypothesis in these models.

6.Robustness Check

Bera, Sosa-Escudero and Yoon locally robust test helps us test residual serial correlation against AR(1) residuals in a pooled OLS model. It is useful in that it helps us detect “the right direction of the departure from the null” (Croissant and Millo, 2018). The result below presents the p-value being much lower than 0,05, which leads us to adopt the alternative hypothesis that errors have either serial correlation or random effect.

pbsytest(pooledols1)

## 
##  Bera, Sosa-Escudero and Yoon locally robust test - unbalanced panel
## 
## data:  formula
## chisq = 23.233, df = 1, p-value = 1.435e-06
## alternative hypothesis: AR(1) errors sub random effects

pbsytest(pooledols2)

## 
##  Bera, Sosa-Escudero and Yoon locally robust test - unbalanced panel
## 
## data:  formula
## chisq = 28.556, df = 1, p-value = 9.103e-08
## alternative hypothesis: AR(1) errors sub random effects

On the other hand, Croissant and Millo (2018) points out that the “locally corrected” tests are relatively inferior in terms of statistical properties compared to the tests that are not corrected if the latter tests are correctly specified.If there Their argument is that a better test in the case when there is no serial correlation could be the likelihood-based Lagrange Multiplier Test refined by Honda. Therefore we run LM Test to supplement the above locally robust test and to identify the autocorrelation in the residuals, and the result shows that the p-values for both Pooled OLS models are much less than 0.05, which allows us to adopt the alternative hypothesis that there are significant individual/time effects.

plmtest(pooledols1)

## 
##  Lagrange Multiplier Test - (Honda) for unbalanced panels
## 
## data:  lp_gdp_lagged ~ pe_share
## normal = 38.844, p-value < 2.2e-16
## alternative hypothesis: significant effects

plmtest(pooledols2)

## 
##  Lagrange Multiplier Test - (Honda) for unbalanced panels
## 
## data:  lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost
## normal = 37.44, p-value < 2.2e-16
## alternative hypothesis: significant effects

Therefore, the results from the two tests allow us to conclude that the Pooled OLS models are not relevant to be applied for this data.

Lastly, to determine whether the Fixed-Effects model or the Random-Effects model is proper for this data, we run the Hausman test. The null hypothesis for this test is that the preferred model is random effects. The results for both models below show the p-values being higher than 0.05, which leads us to stick to the null hypothesis. However, as we observed in the previous section, either the Fixed-Effects model or the Random-Effects model does not present any statistical significance, meaning that even if the Hausman test leads us to choose the Random-Effects model, it does not give us much implications.

phtest(fixeff1,randeff1)

## 
##  Hausman Test
## 
## data:  lp_gdp_lagged ~ pe_share
## chisq = 2.5871, df = 1, p-value = 0.1077
## alternative hypothesis: one model is inconsistent

phtest(fixeff2,randeff2)

## 
##  Hausman Test
## 
## data:  lp_gdp_lagged ~ pe_share + mwwhour + healthconpri + educost
## chisq = 5.1683, df = 4, p-value = 0.2705
## alternative hypothesis: one model is inconsistent

7.Conclusion

Based on the regression models and tests we have conducted, it seems that the data we used does not allow us to either accept or reject the hypothesis that ‘the increased level of private sector engagement in the delivery of secondary education services increases overall labour productivity.’ While it may require further analysis based on better sets of data, what we could learn or assume at least from this statistical test is that: i) the impact of the secondary level of education may not be directly related to the level of labour productivity of employees but rather the privatization of higher education or vocational training might give us better insights, ii) we might be able to obtain some meaningful results if we test with the data set for the privatization of education that distinguishes the private ownership of education services, such as private firms, NGOs, or religious groups, and iii) more detailed analysis of the time taken for the educational attainment to have statistically significant impact on individual’s labour productivity, or simply lag structures, would help researchers who study the relationship between education and labour at various levels aggregate or utilize relevant data more effectively.

8.Reference

Croissant and Millo (2018). Panel Data Econometrics with R, ISBN-13:978-1-118-94918-4.

Draxler, A. (2013). International PPPs in Education: New Potential or Privatizing Public Goods’ in S. Robertson, K. Mundy, A. Verger and F. Menashy (eds.) Public Private Partnerships in Education: New Actors and Modes of Governance in a Globalizing World (Cheltenham: Edward Elgar).

Fennell, S. (2012). Why girls’ education rather than gender equality? The strange political economy of PPPs in Pakistan. In: Robertson S, Mundy K (Eds) Public-private partnerships in education: new actors and modes of governance in a globalizing world. Cheltenham: Edward Elgar Publishing.

Steiner-Khamsi, G. & Draxler, A., eds. (2018). The state, business, and education: Public-private partnerships revisited. Cheltenham, UK: E. Elgar. Open-access book.

Associate Professor of International Relations and Political Science

International institutions and political networks.

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