Dear all, I am trying to model variation of distribution of species assemblages according to environmental variables. For that I use a log linear multinomial regression. In order to select variables that mostly discriminate the assemblages, I tried to apply a hierarchical partitioning protocol to my data set. For that I have adapted the all.regs() for multinomial model. The problem is that I couldn't adapt partition() as I don't manage to access the C code ("hierpart") which is called in this function. This is a black box for me. When I run partition() with the Log Likelihood values obtained for the hierarchy of multinomial model, I obtain negative values for Independenr contribution. This suggest that there is a bug somewhere in my protocole. I suppose that I missused partition(). Maybe my log lokelihood (multinomial one) is not appropriate. As someone had ever met this problem and could help me? Many thanks Am?lie
Hello, I iterate my question concerning hierarchical partitioning: Is it possible to run that for a multinomial model? I have adapted the function hier.part ("hier.part" package) to my multinomial model. I met a problem with the partition() function: I obtain NEGATIVE Independent contributions! It seems to be a huge error! Unfortunately, I cannot access the script as it calls a C code. Consequently this function is a black box for me. Could anyone help me? I really need to investigate this independent contributions! Thanks a lot, Am?lie Vaniscotte (Phd) Department of Environmental Biology UsC INRA EA3184MRT Institute for Environmental Sciences and Technology University of Franche-comt? Place Leclerc, 25030 Besan?on cedex FRANCE Tel. : +33 (0)381 665 714 Fax : +33 (0)381 665 797 E-m at il: amelie.vaniscotte at univ-fcomte.fr http://lbe.univ-fcomte.fr/