bugs or imperfect implementation?
On Fri, 8 Feb 2002, Chong Gu wrote:
I am using R to teach, and here are a couple of things that I thought
would work didn't work.
1. I noticed the utility data(***,package=***) recently and like it
very much, but unless I type in the whole word "package" I'll get an
error in 1.4.0. For example, data(cats,package=MASS) works fine but
data(cats,pac=MASS) doesn't.
2. drop1 doesn't seem to be as smart as before. In the sequence
below, drop1 didn't produce what I expected it to produce.
data(HairEyeColor); lab<-dimnames(HairEyeColor)
HairEye<-cbind(expand.grid(Hair=lab$Hair,Eye=lab$Eye,
Sex=lab$Sex),Fr=as.vector(HairEyeColor))
HairEye.fit<-glm(Fr~.^2,poisson,HairEye)
drop1(HairEye.fit)
The following sequence however works.
HairEye.fit<-glm(Fr~(Hair+Eye+Sex)^2,poisson,HairEye)
drop1(HairEye.fit)
It's not a change in drop1, though, where the basis of this (drop.scope) is unchanged since 1999. I suspect a side effect of changes in the formula/terms handling. Do you know when it did work?
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272860 (secr) Oxford OX1 3TG, UK Fax: +44 1865 272595 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._