黃河泉 发表于 2019-6-28 10:05
就是用 xthreg,要看啥?
xtunitroot ips TE, trend demean
Im-Pesaran-Shin unit-root test for TE
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Ho: All panels contain unit roots Number of panels = 65
Ha: Some panels are stationary Number of periods = 3
AR parameter: Panel-specific Asymptotics: T,N -> Infinity
Panel means: Included sequentially
Time trend: Included Cross-sectional means removed
ADF regressions: No lags included
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Fixed-N exact critical values
Statistic p-value 1% 5% 10%
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t-bar . -4.000 -3.130 -2.900
t-tilde-bar .
Z-t-tilde-bar . *
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* Normality of Z-t-tilde-bar requires at least 7 observations
per panel with balanced data and a time trend.
是这样的,在做面板数据单位根检验时遇到一些问题,从2012-2016年,但是两年为一间隔,也就是说只有三年数据,但做单位根检验时,比如LLC、IPS、Fisher等检验均出不来结果,是年份太少吗