Hi Michael, > -----Original Message----- > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Michael > Friendly > Sent: Thursday, June 29, 2017 9:04 AM > To: Benoît PELE <benoit.p...@acoss.fr>; r-help@r-project.org > Subject: Re: [R] Help : glm p-values for a factor predictor > > On 6/29/17 11:13 AM, Benoît PELE wrote: > > My question is about the factor predictors with several levels. R > > provides only the pvalues for each level whereas i need an overall > > pvalue for testing the predictor. > > What you ask is provided by anova() -- type I tests, and car::Anova() -- Type > II > & III tests. > > Factors in stepwise methods must be handled specially, to allow all levels to > be included/excluded together. I don't know of R software that does this.
The step() function and stepAIC() in MASS both keep terms together and obey marginality. Best, John > > HTH > > -Michael > > ______________________________________________ > 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. ______________________________________________ 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.
