农业集聚对农业面源污染的影响——基于中国地级市面板数据门槛效应分析
邓晴晴, 李二玲, 任世鑫

Impact of agricultural agglomeration on agricultural non-point source pollution: Evidences from the threshold effect based on the panel data of prefecture-level cities in China
DENG Qingqing, LI Erling, REN Shixin
表4 门槛模型结果(lnCOD作为被解释变量)
Tab. 4 Estimation results of threshold model (Dependent variable: lnCOD)
变量 ① THR ② OLS ③ RE ④ FEI ⑤ FER ⑥ 2SLS ⑦ RT
lnagg
(lnagg≤0.976)
0.474***
(30.83)
0.718***
(31.47)
0.496***
(32.97)
0.474***
(30.83)
0.474***
(9.61)
0.781***
(20.98)
0.135***
(8.37)
lnagg
(lnagg>0.976)
0.416***
(30.03)
0.610***
(26.76)
0.438***
(32.26)
0.416***
(30.03)
0.416***
(8.00)
0.687***
(19.32)
lnagdp 0.358***
(24.72)
0.179***
(10.20)
0.340***
(24.89)
0.358***
(24.72)
0.358***
(7.20)
0.143***
(4.86)
0.386***
(22.71)
lnps -0.032
(-1.30)
-0.244***
(-8.97)
-0.020
(-0.81)
-0.032
(-1.30)
-0.032
(-0.74)
-0.290***
(-6.46)
-0.023
(-0.78)
lnas 0.319***
(14.20)
0.577***
(24.46)
0.384***
(17.76)
0.319***
(14.20)
0.319***
(6.94)
0.526***
(17.30)
0.423***
(16.20)
lner 0.031***
(7.21)
0.097***
(13.96)
0.043***
(9.92)
0.031***
(7.21)
0.031***
(3.76)
0.088***
(8.27)
0.019***
(3.25)
lnpc 0.265***
(4.74)
0.229***
(4.81)
0.169***
(3.51)
0.265***
(4.74)
0.265**
(2.55)
0.172***
(2.94)
0.473***
(7.23)
lnea -0.016*
(-1.88)
-0.243***
(-17.59)
-0.029***
(-3.34)
-0.016*
(-1.88)
-0.016
(-1.58)
-0.220***
(-6.97)
-0.007
(-0.72)
_cons 7.231***
(42.93)
8.490***
(47.30)
7.179***
(45.51)
7.231***
(42.93)
7.231***
(20.83)
8.946***
(28.87)
6.719***
(34.08)
F-test 138.10
[0.000]
138.10
[0.000]
132.70
[0.000]
LM-test 9654.92
[0.000]
Hausman test 3699.42
[0.000]
Wald test 89862.7
[0.000]
Overidentification test 0.397
[0.8200]
Weak instruments
test(F statistic)
3065/1633[0.000]
R-sq 0.471 0.827 0.751 0.471 0.471 0.831 0.269
Observation 3033 3033 3033 3033 3033 2359 3033