sergiocorreia / ppmlhdfe

Poisson pseudo-likelihood regression with multiple levels of fixed effects
http://scorreia.com/software/ppmlhdfe/
MIT License
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Red Numbers for "min(eta)" Despite Seemingly Achieving Convergence #22

Open garethcao opened 2 months ago

garethcao commented 2 months ago

When conducting empirical analysis using the command ppmlhdfe, I got the message as displayed in the following graph.

The regression is specified as: ppmlhdfe Y posttreat, absorb(i.unit##c.T i.time##c.distance1 i.time##c.distance2) vce(cluster unit) separation(mu)

I noticed the message "Converged in 31 iterations and 255 HDFE sub-iterations (tol = 1.0e-08)", which seems to suggest that the estimation has been finished. However, the numbers in red color reported after "min(eta) =" remind me that something might be wrong and the estimates might not be reliable. Is the regression result reasonable and what should I do if the answer is no? Thanks.

Stata_Message