Dear colleagues,
I am looking for a package to analyze rank-order data in the form of 
regression. My outcome (dependent) variable is a rank ordering in the 
sense that the respondents to a  questionnaire were asked a single question: to assign the 
values 1 to 4 to four different objects (e.g. to rank four cars as best , second best etc). Their first preference was number 1, their second 
was  number 2 etc. So, for each respondent we have four observations. 
My
 first reaction was to analyze the data as a repeated-measures design 
where I consider the four rankings as four observations for the same 
person (one response per option). This would be an easy case of ordinal 
regression (e.g. proportional odds model) using the excellent package http://biostat.mc.vanderbilt.edu/Rrms of Frank Harrel (thank you Frank). However, these are not four independent observations per person, 
because if a respondent assigned the values to the first three objects, 
then the rank of the fourth object is pre-determined. Does anyone know if there is a package that can fit a more appropriate model such as the Sin‐Ho Jung 
and  Zhiliang Ying (2003) "Rank‐based regression with repeated 
measurements data", Biometrica, 90 (3), 732-740. 

Any other ideas will be
 well received. Thank you
 
Dr. Iasonas Lamprianou
Department of Social and Political Sciences
University of Cyprus
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