st: model specification of poisson and xtpoisson

["Bin Sun" <sun.159@osu.edu>]

Dear all,
I have a question on the model specification of the command xtpoisson and poisson

for poisson, is the specification y=exp(xb+error) or y=exp(xb)+error?

for xtpoisson, fe, is the specification y=exp(xb+individual+error) or y=exp(xb)+individual+error or y=exp(xb+individual)+error?

thanks a lot

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