各位大神么,最近在做面板tobit回归,我的因变量是0-1的,逛了一遍论坛,有的说面板数据应该用xttobit回归,截面用tobit回归,还想确定下该如何选择模型?另外以下分别是我用xttobit和tobit做的分析,应该怎么分析以下结果呢,有几个自变量不显著是不是代表不能放进模型?还请各位能不吝赐教,一点小小的提醒也是很大的帮助,谢谢各位!
Random-effects tobit regression Number of obs = 2,514
Group variable: stock Number of groups = 601
Random effects u_i ~ Gaussian Obs per group:
min = 1
avg = 4.2
max = 6
可以help xttobit,查看帮助中第一行的PDF文件。关于结果的描述
The results from a tobit regression can be interpreted as we would those from a linear regression.
Because the dependent variable is log transformed, the coefficients can be interpreted in terms of a
percentage change. We see, for example, that on average, union members make 14.3% more than
nonunion members.
The output also includes the overall and panel-level variance components (labeled sigma e and
sigma u, respectively) together with rho(此处略去一个公式)
which is the percent contribution to the total variance of the panel-level variance component.
When rho is zero, the panel-level variance component is unimportant, and the panel estimator is
not different from the pooled estimator. A likelihood-ratio test of this is included at the bottom of
the output. This test formally compares the pooled estimator (tobit) with the panel estimator. In this
case, we reject the null hypothesis that there are no panel-level effects.