WARNING: a "bug-wrong" in margins

[josef...@gmail.com]

https://github.com/statsmodels/statsmodels/issues/3695

discrete_model Margins (and by implication most likely also GLM and GEE) adjust the wrong column for option `dummy=True` if the constant column comes before the dummy column(s).

That's another case of not having enough combinations of options in the unit test case.

(But as I mentioned before, having all option combinations unit tested is impossible unless we want to move to 90% of the code base being unit tests.)

Josef
https://www.reddit.com/r/ProgrammerHumor/search?q=unit+test&restrict_sr=on&sort=relevance&t=all

(link from Julia forum)