Iasonas Lamprianou wrote:> Dear colleagues,
>
> i am carrying out an ordinal regression model. I try it on SPSS but I
"flirt" with R as well. I have a few questions.
>
> 1. What is the most reliable/tested/trusted package for ordinal regression
in the R world?
>
> 2. Also, I have a statistical question. What is the danger of having to
many 'empty cells' in ordinal regression? How many empty cells are too
many? Do you have a reference for me to read?
>
> Thank you for the support
>
>
> Dr. Iasonas Lamprianou
Not sure what is the most trusted but the lrm function in the rms
package does proportional odds and continuation ratio models (the latter
with a trick to expand the dataset). Nearly empty cells are not a
problem unless you allow for non-proportionality (e.g., interaction
between X and Y).
Frank
>
>
> Assistant Professor (Educational Research and Evaluation)
> Department of Education Sciences
> European University-Cyprus
> P.O. Box 22006
> 1516 Nicosia
> Cyprus
> Tel.: +357-22-713178
> Fax: +357-22-590539
>
>
> Honorary Research Fellow
> Department of Education
> The University of Manchester
> Oxford Road, Manchester M13 9PL, UK
> Tel. 0044 161 275 3485
> iasonas.lamprianou at manchester.ac.uk
>
>
>
--
Frank E Harrell Jr Professor and Chairman School of Medicine
Department of Biostatistics Vanderbilt University