I'm quite sure the VGAM package has been installed because I used it to estimate the model before I use summary(). One reason I can guess is that the default method for summary() is S3, but here it is S4. But I'm not sure and don't know what to do with that. Here is an example you can reproduce:
counts = c(18,17,15,20,10,20,25,13,12) outcome = gl(3,1,9) treatment = gl(3,3) print(d.AD <- data.frame(treatment, outcome, counts)) vglm.D93 = vglm(counts ~ outcome + treatment, family=poissonff) summary(vglm.D93) With this, I got: > summary(vglm.D93) Length Class Mode 1 vglm S4 If I just type "vglm.D93", I got: Call: vglm(formula = counts ~ outcome + treatment, family = poissonff) Coefficients: (Intercept) outcome2 outcome3 treatment2 treatment3 3.044522e+00 -4.542553e-01 -2.929871e-01 7.766813e-16 3.009745e-16 Degrees of Freedom: 9 Total; 4 Residual Residual Deviance: 5.129141 Log-likelihood: -23.38066 Looking forward to see more advices. Thanks. Harry On Sat, Aug 15, 2009 at 8:18 PM, Ronggui Huang <ronggui.hu...@gmail.com>wrote: > I cannot reproduce what you mentioned. One possible is that you use > summary() without loading VGAM package. > > > 2009/8/16 Hongwei Dong <pdxd...@gmail.com>: > > Hi, R users, > > I'm using the function "vglm" to estimate a multinomial logit model. > Every > > time I use "summary()" to ask for the coefficients and std error, I got > > this: > > > > Length Class Mode > > 1 vglm S4 > > > > Anyone know what's wrong here? Thanks. > > > > Harry > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > 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. > > > > > > -- > HUANG Ronggui, Wincent > PhD Candidate > Dept of Public and Social Administration > City University of Hong Kong > Home page: http://asrr.r-forge.r-project.org/rghuang.html > [[alternative HTML version deleted]] ______________________________________________ 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.