Dear All, I am learning to use fitDiscrete in geiger recently. Results on several discrete characters look normal except for the following one. Can someone please tell me why the values of log-likelihood, AIC, and AICc are so large? Thanks a lot.
> ER<-fitDiscrete(tree, aabb, model="ER") > ARD<-fitDiscrete(tree, aabb, model="ARD") > ER GEIGER-fitted comparative model of discrete data fitted Q matrix: aa bb aa -5.915287 5.915287 bb 5.915287 -5.915287 model summary: log-likelihood = -99999999999999996973312221251036165947450327545502362648241750950346848435554075534196338404706251868027512415973882408182135734368278484639385041047239877871023591066789981811181813306167128854888448.000000 AIC = 199999999999999993946624442502072331894900655091004725296483501900693696871108151068392676809412503736055024831947764816364271468736556969278770082094479755742047182133579963622363626612334257709776896.000000 AICc = 199999999999999993946624442502072331894900655091004725296483501900693696871108151068392676809412503736055024831947764816364271468736556969278770082094479755742047182133579963622363626612334257709776896.000000 free parameters = 1 Convergence diagnostics: optimization iterations = 100 failed iterations = 0 frequency of best fit = 1.00 object summary: 'lik' -- likelihood function 'bnd' -- bounds for likelihood search 'res' -- optimization iteration summary 'opt' -- maximum likelihood parameter estimates > ARD GEIGER-fitted comparative model of discrete data fitted Q matrix: aa bb aa -3.629411e-149 3.629411e-149 bb 3.629411e-149 -3.629411e-149 model summary: log-likelihood = -99999999999999996973312221251036165947450327545502362648241750950346848435554075534196338404706251868027512415973882408182135734368278484639385041047239877871023591066789981811181813306167128854888448.000000 AIC = 199999999999999993946624442502072331894900655091004725296483501900693696871108151068392676809412503736055024831947764816364271468736556969278770082094479755742047182133579963622363626612334257709776896.000000 AICc = 199999999999999993946624442502072331894900655091004725296483501900693696871108151068392676809412503736055024831947764816364271468736556969278770082094479755742047182133579963622363626612334257709776896.000000 free parameters = 2 Convergence diagnostics: optimization iterations = 100 failed iterations = 0 frequency of best fit = 1.00 object summary: 'lik' -- likelihood function 'bnd' -- bounds for likelihood search 'res' -- optimization iteration summary 'opt' -- maximum likelihood parameter estimates > ER$opt$aicc [1] 2e+200 > ARD$opt$aicc [1] 2e+200 Sincerely, Lei [[alternative HTML version deleted]] _______________________________________________ R-sig-phylo mailing list - R-sig-phylo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-phylo Searchable archive at http://www.mail-archive.com/r-sig-phylo@r-project.org/