search for: dad_class_new

...ng message when I am fitting a generalized mixed model (mod_2) and I don't understand why because when I add just an interaction factor the model works perfectly (mod_1). Does anyone know what it happpens ? Thanks, Aïda   > mod_1<-lmer(sur15~soeviv15_4plus+frviv15_4plus+frat_15death+dad_class_new+soeviv15_4plus:dad_class_new +frviv15_4plus:dad_class_new+ aine+ageatmumdeath+(1|newparish)+(1|mumID)+(1|cohorte), + weights=prop_off_tracked_to_age_15,family=poisson, data=basepreindust2_sur15,RMEL=F) > mod_1 Generalized linear mixed model fit by the Laplace approximation Formula: sur15 ~ soev...