Table 9.

Robustness test: replacement of explained variables

Variables	Model1	Model2	Model3	Model4	Model5
L.EFF	0.502***	0.457***	0.640***	0.535***	0.496***
	9.21	8.66	17.34	8.41	9.17
DIF	0.908***
	11.02
DIF2	− 1.409***
	− 6.56
COV		0.779***
		9.06
COV2		− 1.292***
		− 6.08
DIGI			1.009***
			9.67
DIGI2			− 1.488***
			− 8.02
INSU				0.343***
				10.38
INSU2				− 0.236***
				− 5.57
CRE					0.656***
					3.37
CRE2					− 1.206*
					− 1.74
C	0.402***	0.511***	0.336***	0.423***	0.492***
	4.58	4.02	4.34	4.16	3.39
Control Variable	YES	YES	YES	YES	YES
AR(1)P value	0.001	0.001	0.001	0	0.001
AR(2)P value	0.209	0.169	0.21	0.139	0.165
Sargan-P value	1	1	1	1	1

Values in parentheses are z-values

*Significant at the 10% level; **significant at the 5% level; ***significant at the 1% level