time是2019-2020两年内的八个季度,
命令是: xtreg margin lnassets cfmw lnm2 beta rcsi300 i.time,fe r
显示如下:
note: 22006.time omitted because of collinearity
note: 22097.time omitted because of collinearity
note: 22189.time omitted because of collinearity
这三条怎么解决,求助。
Fixed-effects (within) regression Number of obs = 2,384
Group variable: fundid Number of groups = 298
R-sq: Obs per group:
within = 0.2531 min = 8
between = 0.4982 avg = 8.0
overall = 0.3053 max = 8