On Tue, 25 Sep 2001 12:27:27 GMT, Jorge Luis Ojeda Cabrera <jojeda@posta.unizar.es> wrote in message <20010925.12272700@macdesp8.unizar.es>:
When fitting model 'y~1', the 'lm' response is ok, but it is not possible to get predictions using 'predict'. May be this is a bug, at least i think it is somehow inconsistent.
It still appears in 1.3.1, I think it's a bug. It shows up when you use the newdata parameter to predict.lm; if you just ask for predictions without specifying the x value things are fine:
d _ data.frame(x=runif(5),y=runif(5)) d1.lm _ lm(y ~ 1, data=d) # This one is okay: predict(d1.lm)
1 2 3 4 5 0.486269 0.486269 0.486269 0.486269 0.486269
# This one triggers the bug: predict(d1.lm,newdata=data.frame(x=0.5))
Error in model.matrix.default(delete.response(tt), newdata, contrasts
= object$contrasts, :
subscript out of bounds
There are 3 lines in model.matrix.default that assume that there is at
least one predictor in the model: they index various things by "-1"
to remove it. I can't follow what's going on there well enough to fix
it.
Duncan Murdoch
Version:
platform = i386-pc-mingw32
arch = x86
os = Win32
system = x86, Win32
status =
major = 1
minor = 3.1
year = 2001
month = 08
day = 31
language = R
Windows 98 4.10 (build 1998)
Search Path:
.GlobalEnv, package:ctest, Autoloads, package:base
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel 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-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._