Table 1.

Model selection table for mainland China.

	Case 1	Case 2	Case 3
${\beta }_s$	0.5583 (0.5522–0.5643)	0.7401 (0.7328–0.7475)	0.7580 (0.7545–0.7615)
${\beta }_{sw}$	0.1125 (0.1086–0.1165)	0.2761 (0.2713–0.2809)	0.2798 (0.2788–0.2808)
${\beta }_h$	0.0676 (0.0662–0.0691)	0.0942 (0.0924–0.0960)	0.0752 (0.0727–0.0777)
ε (${10}^9$)	-	1.1846 (1.1844–1.1848)	-
M (${10}^9$)	-	-	1.2911 (1.2910–1.2912)
$AIC$	177.9735	180.0358	179.9576
$AI{C}_c$	181.4021	186.7025	186.6243
Δ $AI{C}_c$	0	5.3004	5.2222