Table 3.

Matching Test for Main Covariates

Variables		Mean		Variance		SMD	P-value
		Processing group	Control group	Processing group	Control group
Age	Before matching	35.56	36.59	52.97	57.89	− 0.000071	0.000000
	After matching	35.56	35.56	52.97	52.97	0.000000	1
Edu	Before matching	0.374	0.2722	0.2341	0.1981	0.001598	0.000000
	After matching	0.374	0.374	0.2341	0.2341	0.000000	1
Party_member	Before matching	0.03981	0.03155	0.03823	0.03056	0.000794	0.000001
	After matching	0.03981	0.03981	0.03823	0.03823	0.000000	1
Work	Before matching	0.8585	0.8318	0.1215	0.1399	0.000808	0.000932
	After matching	0.8585	0.8585	0.1215	0.1215	0.000000	1
Marital	Before matching	0.9741	0.9696	0.02525	0.02952	0.000655	0.601395
	After matching	0.9741	0.9741	0.02525	0.02525	0.000000	1
Insurance	Before matching	1.011	0.9805	0.09868	0.1165	0.001136	0.000855
	After matching	1.011	1.011	0.09868	0.09868	0.000000	1
Child	Before matching	1.487	1.577	0.5136	0.5673	− 0.000644	0.000000
	After matching	1.487	1.487	0.5136	0.5136	0.000000	1
Spo_edu	Before matching	0.3737	0.2933	0.2341	0.2073	0.001262	0.000000
	After matching	0.3737	0.3737	0.2341	0.2341	0.000000	1
Age_gap	Before matching	− 0.2269	− 0.2252	0.08394	0.08391	− 0.000074	0.000000
	After matching	− 0.2269	− 0.2269	0.08394	0.08394	0.000000	1
Ethnic	Before matching	0.1069	0.1146	0.09549	0.1015	− 0.000296	0.000000
	After matching	0.1069	0.1069	0.09549	0.09549	0.000000	1
Income	Before matching	8.833	8.839	0.2675	0.3218	− 0.000082	0.000000
	After matching	8.833	8.833	0.2675	0.2676	0.000000	1
House_ exp	Before matching	0.2189	0.2014	0.04181	0.03751	0.001538	0.000000
	After matching	0.2189	0.2189	0.04181	0.04181	0.000000	1
Range_move	Before matching	0.4778	0.5754	0.2495	0.2443	− 0.001438	0.000000
	After matching	0.4778	0.4778	0.2495	0.2495	0.000000	1
Time_move	Before matching	6.196	6.755	30.83	38.72	− 0.000067	0.000000
	After matching	6.196	6.197	30.83	30.83	0.000000	1

$SMD=\left(\overline{X_T}-\overline{X_C}\right)/\sqrt{S_T^2\left(n_T-1\right)+S_C^2\left(n_C-1\right)/\left(n_T+n_C-2\right)}$, where $\overline{X_T}$ and $\overline{X_C}$ indicate the means of each variable in the treatment and control groups, respectively, additionally, $S_T^2$ and $S_C^2$ represent the variances of each variable in the treatment and control groups, respectively, while $n_T$ and $n_C$ highlight the sample size in the treatment and control groups, respectively