短面板数据需要做平稳性检验嘛?本人选取的是连续五年内204家上市公司的财务数据,用stata在做LLC检验时,当滞后期选择1时,出现如下状况:
levinlin alltax, lag(1)
Levin-Lin-Chu test for alltax Deterministics chosen: constant
Reducing Andrews truncation
no observations
r(2000);
当我滞后期选择0时,则出现检验结果:
levinlin alltax, lags(0)
Levin-Lin-Chu test for alltax Deterministics chosen: constant
Reducing Andrews truncation
Pooled ADF test, N,T = (203,5) Obs = 812
Augmented by 0 lags (average) Truncation: 2 lags
coefficient t-value t-star P > t
-0.91011 -38.948 -34.28459 0.0000
刚接触计量的小白,请前辈们赐教,我为什么会出现这种问题啊 |
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