Hi,

I'm running a panel regression. These are my panel commands, followed by regression commands for random effects and fixed effects and hausman test. But the hausman test says,

chi2(0) = (b-B)'[(V_b-V_B)^(-1)](b-B)
= 0.00
Prob>chi2 = .
(V_b-V_B is not positive definite)


Can someone please guide me? Is there an issue in my data set, panel commands or what?