[R] bugs or imperfect implementation?
Prof Brian D Ripley
ripley at stats.ox.ac.uk
Fri Feb 8 16:21:27 CET 2002
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
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._
More information about the R-help
mailing list