Economic growth, energy consumption and environmental degradation nexus in heterogeneous countries: does education matter?

Environmental Sciences Europe

Table 3 Results of Cointegration Tests

Pedroni Residual Cointegration Test
Variable	High-income		Upper-middle-income		Lower-middle-income		Low-income
Variable	Model 1	Model 2	Model 1	Model 2	Model 1	Model 2	Model 1	Model 2
Panel v-Statistic	2.889***	1.757**	0.572	− 0.474	3.462***	2.893***	1.055	0.966
Panel rho-Statistic	− 2.227**	0.583	− 0.122	1.491	− 1.579*	0.679	− 1.239	0.083
Panel PP-Statistic	− 12.128***	− 12.821***	− 3.626***	− 3.109***	− 7.872***	− 6.013***	− 6.644***	− 5.178***
Panel ADF-Statistic	− 4.460***	− 4.763***	− 0.144	1.461	− 3.363***	-0.674	− 6.691***	− 1.966**
Group rho-Statistic	1.801	3.691	1.585	3.082	1.853	3.354	0.500	1.889
Group PP-Statistic	− 7.955***	− 8.339***	− 3.948***	− 5.005***	− 5.952***	− 5.863***	− 5.624***	− 4.476***
Group ADF-Statistic	− 4.601***	− 4.204***	− 2.634***	− 3.191***	− 2.312**	− 0.964	− 5.241***	− 2.319**
Kao Cointegration Test (ADF)	− 3.111***	− 3.241***	− 3.078***	− 3.205***	2.164**	1.572*	− 1.954**	− 3.303**

^***, **, * represents a statistical rejection level of the null of no cointegration at 1%, 5% and 10% significance levels, respectively