. 2022 Aug 8;30(2):2813–2835. doi: 10.1007/s11356-022-22320-5

Table 4.

Table of SFA regression results in the second stage

Variables	Labor input slack variable		Energy input slack variables		Capital input slack variables
Variables	Labor force factor	Standard deviation	Energy factor	Standard deviation	Capital factor	Standard deviation
Constant term	− 0.267923	0.2429258	0.034946	0.34578	0.05083	0.347717
Constant term	− 1.102899	0.2429258	0.101064	0.34578	0.146182	0.347717
Industrial structure development	0.3555592	0.3059045	0.168391	0.453259	0.271882	0.455922
Industrial structure development	1.1623207	0.3059045	0.371512	0.453259	0.596335	0.455922
Coal energy structure	0.0010656	0.0018788	− 0.00457**	0.002202	− 0.00072	0.002318
Coal energy structure	0.5671753	0.0018788	− 2.07398	0.002202	− 0.3097	0.002318
Urbanization rate	− 0.732657***	0.2508954	0.107842	0.351077	− 0.14074	0.368665
Urbanization rate	− 2.920167	0.2508954	0.307175	0.351077	− 0.38176	0.368665
R&D investment	0.1882084***	0.0445403	0.042221	0.070967	0.050258	0.071209
R&D investment	4.2255733	0.0445403	0.59494	0.070967	0.705786	0.071209
degama2	0.0895316	0.008227	0.135235	0.024727	0.110496	0.014515
degama2	10.882594	0.008227	5.469114	0.024727	7.612759	0.014515
gama	0.0075579	0.0213721	0.289927	0.127714	0.141249	0.101221
gama	0.3536337	0.0213721	2.270121	0.127714	1.395448	0.101221
Log function value	− 61.421396		− 82.614758		− 84.837439
LR one-sided test	6.8534791		18.442006		38.006647