stata处理短面板数据控制时间效应时为什么会t值等为空
R-squared: Obs per group:
Within = 1.0000 min = 20
Between = . avg = 20.0
Overall = 1.0000 max = 20
F(0,92) = .
corr(u_i, Xb) = -0.0000 Prob > F = .
(Std. err. adjusted for 93 clusters in id)
| Robust
rmb | Coefficient std. err. t P>|t| [95% conf. interval]
tone | 8.17e-17 . . . . .
lnnumber | -8.66e-16 . . . . .
jiaocha | -2.62e-16 . . . . .
|
timeid |
2 | .1324249 . . . . .
3 | .1611746 . . . . .
4 | .3016604 . . . . .
5 | .338097 . . . . .
6 | .433431 . . . . .
7 | .3016804 . . . . .
8 | .3662557 . . . . .
9 | .4125601 . . . . .
10 | .3971486 . . . . .
11 | .5844697 . . . . .
12 | .6063016 . . . . .
13 | .6491567 . . . . .
14 | .6539906 . . . . .
15 | .8205891 . . . . .
16 | .8919699 . . . . .
17 | .915349 . . . . .
18 | .9841706 . . . . .
19 | .967843 . . . . .
20 | 1.424018 . . . . .
|
_cons | 1.409334 . . . . .
代码 xtreg rmb tone lnnumber jiaocha i.id, fe r
部分数据
v time month jidu timeid tone rmb number lnnumber jiaocha id
中国 2017 7 3 1 0.3617969 1.40933416 21081 9.956127 3.602095885 2
中国 2017 10 4 2 1.192212 1.541759108 19406 9.873338 11.77111204 2
中国 2018 3 1 3 0.9355314 1.57050878 18164 9.807197 9.174940739 2
中国 2018 6 2 4 1.101312 1.710994525 20007 9.903837 10.90721453 2
中国 2018 8 3 5 1.225671 1.747431169 17276 9.757073 11.95896142 2
中国 2018 12 4 6 1.29119 1.842765161 14975 9.614138 12.41367884 2
中国 2019 1 1 7 1.119524 1.711014557 12696 9.449042 10.5784293 2
中国 2019 5 2 8 1.051545 1.775589899 15594 9.654641 10.15228947 2
中国 2019 7 3 9 0.737029 1.821894298 14079 9.55244 7.040425301 2
中国 2019 12 4 10 1.190705 1.806482754 14279 9.566545 11.39093296 2
中国 2020 2 1 11 -0.7380779 1.99380389 13188 9.487062 -7.002190798 2
中国 2020 5 2 12 -0.8821999 2.015635796 13491 9.509778 -8.389525201 2
中国 2020 9 3 13 -0.5122259 2.058490857 12594 9.440976 -4.835912428 2
中国 2020 12 4 14 0.2761493 2.063324808 9577 9.16712 2.531493771 2
中国 2021 2 1 15 0.280089 2.229923289 12677 9.447545 2.646153432 2
中国 2021 6 2 16 0.4964891 2.30130411 13552 9.51429 4.723741279 2
中国 2021 8 3 17 0.4499097 2.324683202 12044 9.396322 4.227496412 2
中国 2021 11 4 18 0.9630019 2.393504727 12980 9.471165 9.12074989 2
中国 2022 3 1 19 0.7141712 2.377177156 10684 9.276503 6.625011279 2
中国 2022 5 2 20 0.6538082 2.833352308 11559 9.35522 6.116519549 2
丹麦 2017 9 3 1 -1.269905 1.40933416 147 4.990433 -5.841581291 3
丹麦 2017 11 4 2 -0.2897895 1.541759108 98 4.584968 -0.922501064 3
丹麦 2018 3 1 3 -1.651493 1.57050878 101 4.61512 -6.762959927 3
丹麦 2018 6 2 4 -1.455744 1.710994525 98 4.584968 -6.660725148 3
丹麦 2018 9 3 5 -0.7991136 1.747431169 172 5.147494 -4.714204207 3
丹麦 2018 11 4 6 -1.574372 1.842765161 198 5.288267 -7.600085802 3
丹麦 2019 3 1 7 -1.371653 1.711014557 151 5.01728 -6.61626205 3
丹麦 2019 4 2 8 -1.561072 1.775589899 145 4.976734 -7.286177459 3
丹麦 2019 8 3 9 -1.736829 1.821894298 200 5.298317 -8.88234764 3
丹麦 2019 10 4 10 -1.469356 1.806482754 165 5.105946 -7.880787672 3
丹麦 2020 1 1 11 -2.960795 1.99380389 209 5.342334 -16.1787136 3
丹麦 2020 4 2 12 -2.264889 2.015635796 143 4.962845 -11.29703822 3
丹麦 2020 8 3 13 -2.027866 2.058490857 182 5.204007 -11.00136967 3
丹麦 2020 12 4 14 -1.242177 2.063324808 95 4.553877 -6.179579212 3
丹麦 2021 2 1 15 -1.006358 2.229923289 94 4.543295 -5.298127118 3
丹麦 2021 6 2 16 -0.5940366 2.30130411 38 3.637586 -1.825180965 3
丹麦 2021 8 3 17 -1.141131 2.324683202 43 3.7612 -5.519940881 3
丹麦 2021 12 4 18 -1.349856 2.393504727 43 3.7612 -4.851974328 3
丹麦 2022 2 1 19 -2.044719 2.377177156 44 3.78419 -8.458069558 3
丹麦 2022 4 2 20 -0.4520744 2.833352308 58 4.060443 -2.642656087 3