> ----- Original Message ----- > From: "Erika Known" <[EMAIL PROTECTED]> > To: <r-help@r-project.org> > Sent: Tuesday, October 14, 2008 11:43 AM > Subject: [R] IAA test on my multinomial logit > > > Hi all > > > > I'm trying to immigrate from Stata and I want to preform a IIA test > > (Independence of Irrelevant Alternatives) on my multinomial logit model > > in R, but I can't seem to find a package that dos the trick. I've been > > looking at > > http://bm2.genes.nig.ac.jp/RGM2/R_current/library/systemfit/man/hausman.systemfit.html > > but I can't figure out what to do! I normally just type 'mlogtest, > > hausman base' to get the test in Stata. I can even use 'mlogtest, > > smhsiao base' to get the Small-Hsiao tests of IIA assumption. > > > > according to the literature there is also other tests.. thou I cant seem > > to find any off them in R. > > > > Thank for the help. > > > > Erika
On Tue, 14 Oct 2008 12:11:45 -0500, Gilbert Brenes wrote > If I'm not wrong, the test for IIA is the Hausman test. > > Look for hausman.systemfit in the systemfit package. > > Gilbert > Hi again! Thanks for your answer! Thou that's where I got stuck too, so to say. The link I send was to the systemfit package, but I can't seem to get it to working. This is what I do: model_01 <- multinom(Y ~ X1 + X2 + X3 + X4 + X5 + X6, data=data, contrasts = NULL, Hess = TRUE, summ = 0, censored = FALSE, model = TRUE) That's running like a dream! - and the I try: > systemfit(model_01) Error in systemfit(dyls.model01) : argument 'formula' must be an object of class 'formula' or a list of objects of class 'formula' In addition: Warning messages: 1: In if (class(formula) == "formula") { : the condition has length > 1 and only the first element will be used 2: In if (class(formula) == "list") { : the condition has length > 1 and only the first element will be used >hausman.systemfit(model_01) Error in coef(results3sls) : argument "results3sls" is missing, with no default I relly want to imigrate, but I need help! Just tell mer a website or wher I can read my way out of it. Do you think you can give me one more hint? Sorry for my ignorance Erika ______________________________________________ R-help@r-project.org mailing list 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.