Study on the Operation Efficiency of Toll Roads in China from the Perspective of Scale Economy
Table 6
Parameter estimation results.
(I)
(II)
(III)
(IV)
Pooled OLS
Panel GMM
Toll
14.65
5.858
10.42
5.858
(4.72)
(5.24)
(5.81)
(5.24)
Toll_int
−39.54
−24.34
−26.51
−24.34
(−2.94)
(−4.31)
(−2.33)
(−4.31)
Urban
−0.0188
−0.00409
−0.00882
−0.00409
(−4.26)
(−2.57)
(−2.29)
(−2.57)
Unemploy
−0.123
−0.0432
−0.178
−0.0432
(−1.93)
(−3.80)
(−3.08)
(−3.80)
Eply
0.220
0.0276
0.210
0.0276
(4.39)
(1.51)
(5.61)
(1.51)
Toll_Station
−1.623
0.771
−1.640
0.771
(−3.96)
(7.42)
(−2.33)
(7.42)
Ltc
0.102
0.0837
0.129
0.0837
(2.71)
(4.90)
(2.82)
(4.90)
Ave_Salary
0.0117
−0.198
0.647
−0.198
(0.05)
(−1.54)
(3.39)
(−1.54)
_cons
1.192
0.895
−0.0533
0.895
(1.93)
(4.20)
(−0.08)
(4.20)
Hansen
—
—
1
1
AR
—
—
0.146
0.137
N
174
145
145
145
Note.Statistical significance at the 10% level; statistical significance at the 5% level; statistical significance at the 1% level. The t-statistics calculated with the standard error of heteroscedasticity are reported in brackets.
