近邻匹配

核匹配

半径匹配

Treat × Time

0.016^** (2.42)

0.001^*** (4.17)

0.004^*** (4.12)

T-stat (ATT)

1.97

3.31

3.30

T-stat (Score Unmatched)

4.51

4.51

4.51

Controls

Yes

Yes

Yes

Year

Yes

Yes

Yes

Firm

Yes

Yes

Yes

Observations

8944

8944

8944