Table 12. Endogenous test results.

Variable	Comprehensive effect: Dependent variable: total factor productivity (TFP)
	(1)	(2)	(3)
Estimation method	FGLS	GEE	OLS
DEI	0.4499***	0.3048***	0.4499***
	(8.47)	(12.42)	(8.18)
TD	0.1547***	0.2193***	0.1547***
	(3.23)	(5.62)	(3.12)
FD	0.0465***	0.0208**	0.0465***
	(2.81)	(1.43)	(2.71)
IS	0.0562***	0.0040*	0.0562***
	(2.89)	(0.40)	(2.79)
OPEN	0.0394**	0.0322**	0.0394**
	(1.94)	(1.99)	(1.88)
RD	0.1273***	0.1658***	0.1273***
	(3.10)	(5.39)	(2.99)
constant	-0.0924***	-0.0378**	-0.0924***
	(-3.47)	(-1.52)	(-3.35)
Wald	1348.78	806.43	-
R2	-	-	0.9108
N	120	120	120