Table 12.

Ridge regression results of CO₂ emissions in the Yellow River Basin.

Variable	Parameter	Standard error	Standardised coefficient	t Statistics	p-Value
LnP	0.2826	0.0479	0.2761	5.9062	0.0035
LnA	0.3202	0.0613	0.3188	5.2241	0.0001
LnT	0.0886	0.0505	0.0869	1.7529	0.0005
LnU	− 0.0762	0.0435	0.0715	− 1.7497	0.0006
LnPs	0.1644	0.0271	0.1542	6.0563	0.0002
LnIs	0.0240	0.0527	0.0231	0.4559	0.0003
constant	0.6086	0.7159	0.0000	0.8501	0.0075
	R^2 = 0.9676		F Statistics = 14.9394	Sig.F = 0.0024