Union membership and the wage gap between the public and private sectors: evidence from China

Journal for Labour Market Research

Table 5 Results of union effect on wage for total, public sector and private sector based on the PSM method

	Sample	Treated	Controls	Difference	SE	t-value
(1) One to one Nearest-neighbor e matching (1:1)
Nation	Unmatched	2.581	2.205	0.376	0.020	18.93
	ATT	2.580	2.463	0.117	0.031	3.78
Public	Unmatched	2.625	2.328	0.297	0.024	12.40
	ATT	2.624	2.548	0.077	0.037	2.10
Private	Unmatched	2.479	2.142	0.337	0.036	9.43
	ATT	2.479	2.357	0.122	0.052	2.33
(2) k-Nearest-neighbor matching (1:3)
Nation	Unmatched	2.581	2.205	0.376	0.020	18.93
	ATT	2.580	2.460	0.120	0.026	4.62
Public	Unmatched	2.625	2.328	0.297	0.024	12.40
	ATT	2.624	2.530	0.094	0.031	3.04
Private	Unmatched	2.479	2.142	0.337	0.036	9.43
	ATT	2.479	2.373	0.106	0.044	2.40
(3) Kernel matching
Nation	Unmatched	2.581	2.205	0.376	0.020	18.93
	ATT	2.581	2.483	0.098	0.023	4.20
Public	Unmatched	2.625	2.328	0.297	0.024	12.40
	ATT	2.625	2.534	0.091	0.028	3.21
Private	Unmatched	2.479	2.142	0.337	0.036	9.43
	ATT	2.479	2.359	0.120	0.038	3.13
(4) Radius matching
Nation	Unmatched	2.581	2.205	0.376	0.020	18.93
	ATT	2.580	2.484	0.096	0.024	4.05
Public	Unmatched	2.625	2.328	0.297	0.024	12.40
	ATT	2.625	2.530	0.095	0.029	3.27
Private	Unmatched	2.479	2.142	0.337	0.036	9.43
	ATT	2.474	2.377	0.097	0.039	2.46
(5) Local linear regression matching
Nation	Unmatched	2.581	2.205	0.376	0.020	18.93
	ATT	2.580	2.484	0.096	0.031	3.12
Public	Unmatched	2.625	2.328	0.297	0.024	12.40
	ATT	2.624	2.529	0.096	0.037	2.62
Private	Unmatched	2.479	2.142	0.337	0.036	9.43
	ATT	2.479	2.373	0.106	0.052	2.02

The observable variables include demographic factors (years of schooling, year of work experience, health status, sex, ethnicity, urban hukou, married, CPC membership), work factors (occupation, industry sector), parent’s work status, parent’ CPC membership, province-level region and survey year (2012, 2014, 2016, and 2018) dummies were used in the probit regression model to calculate the propensity matching score. Total samples including public and private sector. Source: Calculated using data from the CFPS of 2010, 2012, 2014, 2016 and 2018
PSM the propensity scores matching method. ATT average treated effect on the treated
***p < 0.01
**p < 0.05
*p < 0.1