On Wed, 2010-07-07 at 20:44 -0300, Luciano Selzer wrote: > Hi Manuel, your problem is that the new variables you created are of numeric > type, while the model was fitted using factor. So the fix is to convert the > new variables to factors so the type matchs
It may need more than that; not tested but I have often run into problems where I had slightly different levels for factors in the prediction data than in the fitting. G > Luciano > > > 2010/7/7 Manuel Spnola <mspinol...@gmail.com> > > > Dear list members, > > > > I am fitting a logistic regression with 5 explanatory factors (which I > > converted to factors): > > > > mod6 = glm(condicion ~ iluminacion + animales + cielo.raso + piso + > > paredes, family=binomial, data=reglog) > > > > I want to obtain the predicted probabilities and the se using the function > > "predict" for some combination of the factors. > > > > iluminacion = 1 > > animales = 0 > > cielo.raso = 0 > > piso = 0 > > paredes = 0 > > > > newdata1 = data.frame(iluminacion, animales, cielo.raso, piso, paredes) > > > > newdata1$cond = predict(mod6, newdata = newdata1, type="response") > > > > > newdata1$cond = predict(mod6, newdata = newdata1, type="response") > > Aviso en model.frame.default(Terms, newdata, na.action = na.action, xlev = > > object$xlevels) : > > variable 'iluminacion' is not a factor > > Aviso en model.frame.default(Terms, newdata, na.action = na.action, xlev = > > object$xlevels) : > > variable 'animales' is not a factor > > Aviso en model.frame.default(Terms, newdata, na.action = na.action, xlev = > > object$xlevels) : > > variable 'cielo.raso' is not a factor > > Aviso en model.frame.default(Terms, newdata, na.action = na.action, xlev = > > object$xlevels) : > > variable 'piso' is not a factor > > Aviso en model.frame.default(Terms, newdata, na.action = na.action, xlev = > > object$xlevels) : > > variable 'paredes' is not a factor > > Error: variables 'iluminacion', 'animales', 'cielo.raso', 'piso', 'paredes' > > were specified with different types from the fit > > > > I don't understand what is wrong. > > Any help will be appreciated. > > > > Best, > > > > Manuel > > > > -- > > Manuel Spnola, Ph.D. > > Instituto Internacional en Conservacin y Manejo de Vida Silvestre > > Universidad Nacional > > Apartado 1350-3000 > > Heredia > > COSTA RICA > > mspin...@una.ac.cr > > mspinol...@gmail.com > > Telfono: (506) 2277-3598 > > Fax: (506) 2237-7036 > > > > _______________________________________________ > > R-sig-ecology mailing list > > R-sig-ecology@r-project.org > > https://stat.ethz.ch/mailman/listinfo/r-sig-ecology > > > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-ecology mailing list > R-sig-ecology@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-ecology -- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% _______________________________________________ R-sig-ecology mailing list R-sig-ecology@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-ecology