[R-sig-ME] glmmadmb beta - error

[Ludovico Frate]

Dear list,I have got the following error message trying to fit this model:
glmmadmb<-(cover~time+summit+direction+(1|plot_id), family = "beta", data = cover_lf)
Error in glmmadmb(cover~time+summit+direction+(1|plot_id),  :   The function maximizer failed (couldn't find parameter file) Troubleshooting steps include (1) run with 'save.dir' set and inspect output files; (2) change run parameters: see '?admbControl';(3) re-run with debug=TRUE for more information on failure modeIn addition: Warning message:running command 'C:\Windows\system32\cmd.exe /c glmmadmb -maxfn 500 -maxph 5 -noinit -shess' had status 1 
str(cover_lf)'data.frame':	50 obs. of  5 variables: $ plot_id  : Factor w/ 48 levels "FEME11","FEME13",..: 5 6 7 8 1 2 3 4 9 10 ... $ summit   : Factor w/ 2 levels "FEM","MAC": 1 1 1 1 1 1 1 1 1 1 ... $ direction: Factor w/ 4 levels "E","N","S","W": 2 2 2 2 1 1 1 1 3 3 ... $ time     : Factor w/ 2 levels "2001","2015": 1 1 1 1 1 1 1 1 1 1 ... $ cover   : num  0.023 0.071 0.063 0.014 0.003 0.035 0.055 0.01 0.065 0.04 ...
cover is the dependent variable that is percentage of cover (0-100) divided by 100 to match the beta distribution. The random effect was included to allow repeated measure on each plot for two time period (time treated as factor).
Thank you in advance,Regards
Ludovico


                                                                                                                                
Dott. For. Ludovico
Frate, Ph.D.
University of Molise - Italy
Environmetrics Lab
http://www.distat.unimol.it/STAT/environmetrica/organico/collaboratori/ludovico-frate-1
Department of Biosciences and Territory - DiBT
Università del Molise.
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