On Fri, 26 Mar 2021 13:41:00 +1300 Abby Spurdle <spurdl...@gmail.com> wrote:
> I haven't checked this, but I guess that the number of students that > *pass* a particular exam/subject, per semester would be like that. > > e.g. > Let's say you have a course in maximum likelihood, that's taught once > per year to 3rd year students, and a few postgrads. > You could count the number of passes, each year. > > If you assume a near-constant probability of passing in each > exam/semester: Then I would assume it would follow the distribution > that you're requesting. <SNIP> Thanks Abby. I've experimented (simulated) a wee bit and found that if I keep the numbers of students (undergrad and grad) exactly constant, then the results are underdispersed. However if the numbers are allowed to vary then the results are overdispersed. It seems that the universe is very reluctant to produce underdispersed pseudo-binomial data! cheers, Rolf -- Honorary Research Fellow Department of Statistics University of Auckland Phone: +64-9-373-7599 ext. 88276 ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
