增加遗漏变量 | 剔除特殊样本 | 剔除首尾年份 | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
(1) PCR | (2) SEI | (3) CEI | (4) PCR | (5) SEI | (6) CEI | (7) PCR | (8) SEI | (9) CEI | |||
lnGather | -0.067*** | -0.035*** | -0.020*** | -0.057*** | -0.029*** | -0.016** | -0.066*** | -0.039*** | -0.013* | ||
(0.010) | (0.005) | (0.007) | (0.011) | (0.006) | (0.007) | (0.011) | (0.006) | (0.007) | |||
_cons | 3.529*** | 1.715*** | 5.179*** | 3.744*** | 1.906*** | 5.035*** | 4.201*** | 1.999*** | 5.812*** | ||
(0.284) | (0.149) | (0.193) | (0.291) | (0.160) | (0.191) | (0.303) | (0.172) | (0.204) | |||
控制变量 | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | ||
城市固定效应 | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | ||
N | 1188 | 1188 | 1188 | 1067 | 1067 | 1067 | 972 | 972 | 972 | ||
R2 | 0.592 | 0.601 | 0.835 | 0.575 | 0.547 | 0.839 | 0.566 | 0.537 | 0.819 |