R help - Dec 2007 - GLM and factor in forular

I used a GLM with a factor variable and wondered about that the first 
factor is missing in the results.
means there is no result for Y1
Is it wrong to use factors in GLM or is there a statistical reason that 
there is no Y1 result ?

X<-rnorm(31:40)
Y<-factor(c(1:10))
glm(X~Y)

Knut

Mark Leeds schrieb:
> That's because the first factor is being used as the
"baseline". This is
> explained in any intro to GLMs text.
>
>
>   
Thank you Mark, I didn't found that hint.

Knut