Hi there Maybe you can find useful The isoreg {modreg} package which does Monotone regression. This is probably what you need to model your data.
Nonetheless be aware you need to code properly your design matrix (use orthogonal polynomial codes) The difference in using MNP or ordered probit is that with Monotonic regression you will have individual partworths utilities. Then you may aggregate your data on an individual level analysis. Hope this helps Regards ********************************************** Massimiliano Marinucci http://personales.ya.com/max_mar/ Ph.D Candidate in Economics Fundamentos del Analisis Económico II (Economía Cuantitativa) Facultad de CC.EE. Universidad Complutense Madrid Campus de Somosaguas Madrid - Spain ********************************************** -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Cela, Jimmy (IHG) Sent: martes, 07 de junio de 2005 12:18 To: 'r-help@stat.math.ethz.ch' Subject: [R] Conjoint in R Hello all, I am trying to apply a conjoint analysis in order to determine the best profile that captures the most preferred combination of levels of given categorical factors. For this a set of factors is given and initially a fractional factorial design has to be produced as a subset of all possible factor levels combinations, sufficient to estimate the main effects utilities. Then the preference for each chosen combination is assessed via surveys on subjects (clients). Preferences are given by ranking profiles ordinally. Conjoint analysis then is applied on the preference data to estimate the utility values - or the "part worth" for each factor level. SPSS 13.0 has a module called CONJOINT that handles such problem from designing the fractional factorial design to the conjoint analysis. What would be the best way to implement such analysis in R? Thank you. Jimmy Cela Decision Sciences InterContinental Hotels Group Inc Atlanta, GA USA ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html