You are right of course, Peter, but I can see where some will get confused. In a formula some symbols and functions are special operators, and others are simple functions. That is the reason one needs I(events/time) to put a rate in as a variable. Someone who types 'offset' at the command line will see that there actually IS a function behind the scenes.
Does anyone see a downside to Bill Dunlap's suggestion where the first step of my formula processing would be to "clean off" any survival:: modifiers? That is, something that will break? After all, the code already has a lot of "if (....) " lines for other common user errors. I could view it as just saving me the time to deal with the 'we found an error' emails. I would output the corrected version as the "call" component. Terry On 8/27/24 03:38, peter dalgaard wrote: > In my view, that's just plain wrong, because strata() is not a function but a > special operator in a model formula. Wouldn't it also blow up on > stats::offset()? > > Oh, yes it would: > >> lm(y~x+offset(z)) > Call: > lm(formula = y ~ x + offset(z)) > > Coefficients: > (Intercept) x > 0.7350 0.0719 > >> lm(y~x+stats::offset(z)) > Call: > lm(formula = y ~ x + stats::offset(z)) > > Coefficients: > (Intercept) x stats::offset(z) > 0.6457 0.1078 0.8521 > > > Or, to be facetious: > >> lm(y~base::"+"(x,z)) > Call: > lm(formula = y ~ base::"+"(x, z)) > > Coefficients: > (Intercept) base::"+"(x, z) > 0.4516 0.4383 > > > > -pd > >> On 26 Aug 2024, at 16:42 , Therneau, Terry M., Ph.D. via >> R-devel<r-devel@r-project.org> wrote: >> >> The survival package makes significant use of the "specials" argument of >> terms(), before >> calling model.frame; it is part of nearly every modeling function. The >> reason is that >> strata argments simply have to be handled differently than other things on >> the right hand >> side. Likewise for tt() and cluster(), though those are much less frequent. >> >> I now get "bug reports" from the growing segment that believes one should put >> packagename:: in front of every single instance. For instance >> fit <- survival::survdiff( survival::Surv(time, status) ~ ph.karno + >> survival::strata(inst), data= survival::lung) >> >> This fails to give the correct answer because it fools terms(formula, >> specials= >> "strata"). I've stood firm in my response of "that's your bug, not mine", >> but I begin >> to believe I am swimming uphill. One person responded that it was company >> policy to >> qualify everything. >> >> I don't see an easy way to fix survival, and even if I did it would be a >> tremendous amout >> of work. What are other's thoughts? >> >> Terry >> >> >> >> -- >> >> Terry M Therneau, PhD >> Department of Quantitative Health Sciences >> Mayo Clinic >> thern...@mayo.edu >> >> "TERR-ree THUR-noh" >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-devel@r-project.org mailing list >> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstat.ethz.ch%2Fmailman%2Flistinfo%2Fr-devel&data=05%7C02%7Ctherneau%40mayo.edu%7C7659a5f0f0d34746966a08dcc6739fed%7Ca25fff9c3f634fb29a8ad9bdd0321f9a%7C0%7C0%7C638603447151664511%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=UAkeksswfFdLwOdzQIOXUPC2Ey255oW%2FX41kptNZNcU%3D&reserved=0 [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
