The offset is just the log of the exposure (I assume -- I have never used Stata) so if you can express your model in terms of exposure you can also express it in terms of offset.
On Fri, Aug 21, 2026 at 4:21 AM iagogv via R-help <[email protected]> wrote: > > Hi all, > > Can an exact Poisson regression be computed with R, instead of using the > standard (glm) Poisson using maximum likelihood? > > I am working with a collegue in a project, and I'd like to reproduce his > method, if not his results. He uses Stata, particularly the expoisson > function (https://www.stata.com/help.cgi?expoisson) in order to compute > the exact Poisson regression, relevant for small samples. > > expoisson fits an exact Poisson regression model, which produces more > accurate inference in small samples than standard > maximum-likelihood-based Poisson regression > > I know about exact Poisson tests > (https://stat.ethz.ch/R-manual/R-devel/RHOME/library/stats/html/poisson.test.html), > but it does not allow to include offset. > > So, is there some way to reproduce exact Poisson regression with R? > > Thanks! > > Best, > > -- > Iago > [[alternative HTML version deleted]] > > ______________________________________________ > [email protected] mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide https://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com ______________________________________________ [email protected] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide https://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
