st: Using xtprobit pa, xtprobit re or xtlogit fe ?

[Claude Francoeur <claude.francoeur@hec.ca>]

Hello,

My data is organized in a panel (100 firms over 5 years) with a binary 
dependent variable.

I get interesting results, using xtprobit, pa or re (N = 581 and no of 
groups = 135). Here are the commands:

xtprobit pw boardcomp compensation shrights disclosure tech mv endet cot 
volat march conc, pa i(i)

xtprobit pw boardcomp compensation shrights disclosure tech mv endet cot 
volat march conc, re i(i)


Using xtlogit and controlling for fixed effects, all coefficients become non 
significant (N = 128 and no of groups = 27)

xtlogit pw boardcomp compensation shrights disclosure tech mv endet cot 
volat march conc, fe i(i)

Why does xtlogit eliminate so many observations and all significance?  Is 
xtlogit appropriate ?

Thanks,

Claude 

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