On Sep 25, 2009, at 6:29 AM, Ashta wrote:
> Dear R-users,
>
> Suppose I have the following sample of data,
>
> 0 1 2 4 3
> 1 2 1 3 1
> 1 3 3 4 1
> 0 1 2 1 2
> 1 4 1 4 2
> 1 2 2 1 1
>
> The first variable is the response variable where 0 is defective and 1
> normal. The other four factors( x1,x2,x3,x4) that influence the
> outcome. I
> want to fit a binomial model . How do I do that? I am guessing the
> response
> variable should be transformed but not sure which family of
> transformation
> to use.
> It is easy to do it in SAS but I just want to learn using R
>
> Any help is highly appreciated
>
> Ashta
Presuming that your reference to SAS is to PROC LOGISTIC, then in R
you would use glm() with 'family = binomial'.
Using:
help.search("logistic regression")
would get you a lot of hints.
See ?glm for more information, or alternatively, the lrm() function in
Frank's 'rms' package on CRAN.
I would however hope that your actual working data set is much larger,
as you don't have enough data above to support a single covariate,
much less 4.
HTH,
Marc Schwartz