Table 3.

Results of OLS and principal component regression

Indicator	OLS regression		Principal component regression
	β coefficient*	VIF	β coefficient*	VIF
Intercept	−2.148 (1.207)	0	−3.104 (0.513)***	0.531
Urban (reference: rural)	0.604 (0.170)**	2.602	0.209 (0.034)***	0.035
Gini coefficient of property	1.569 (0.778)	1.122	1.979 (0.673)**	0.687
Logarithms of the average property	0.182 (0.151)	4.723	0.114 (0.019)***	0.024
Negative Gini coefficient of education	1.686 (1.305)	4.058	0.351 (0.255)	0.345
Average educational duration	−0.117 (0.097)	12.948	0.041 (0.008)***	0.009
Educational return†	0.256 (0.240)	1.358	0.195 (0.033)***	0.216

*P<0.05; **p<0.01; ***p<0.001.

*The numbers outside the brackets are means, while the numbers in the brackets are SEs.

†Educational return was calculated through the Mincerian model.

OLS, ordinary least squares; VIF, variance inflation factor.