Table 5.

Regression results of main influencing factors on UEI (n = 20)

Ecological efficiency index
Independent variable	Standardization coefficient	t	p	R2	D-W value	F
Constant	–	5.475	0.000082**	0.978	2.435	F(5,14) = 451.367 p = 5.7730E-15
Raw coal emergy	− 0.209	− 5.385	0.000127**
Grain emergy	0.055	0.899	0.384
Solid waste emergy	− 0.955	− 3.989	0.001**
Input emergy	− 0.023	− 1.132	0.286
Social fixed asset investment	0.091	0.325	0.773

*p < 0.05 **p < 0.01