Hi, I have a problem with mixed effect model (multilevel). My model that is written in following formulation using the lme4 package and Zelig package: mylogit<- lmer(OVERFLOW ~ ALTEZZA + INTENSITA + ( 1 | CODICE), familybinomial(link = "probit"),data = dati) OVERFLOW can be 0 or 1 and represents the activation of a combined sewer overflow ALTEZZA is integer and reppresents the total precipitation occured during an event INTENSITA is integer and reppresents the maximun precipitation intensity occured during an event CODICE are different (13) combined sewer overflows I am analysing 480 OVERFLOWs. Summary Generalized linear mixed model fit by the Laplace approximation Formula: OVERFLOW ~ ALTEZZA + INTENSITA + (1 | CODICE) Data: dati AIC BIC logLik deviance 509.2 525.9 -250.6 501.2 Random effects: Groups Name Variance Std.Dev. CODICE (Intercept) 0.73159 0.85533 Number of obs: 480, groups: CODICE, 13 Fixed effects: Estimate Std. Error z value Pr(>|z|) (Intercept) -0.818969 0.264502 -3.096 0.00196 ** ALTEZZA 0.023416 0.004184 5.596 2.19e-08 *** INTENSITA 0.069759 0.021693 3.216 0.00130 ** --- Signif. codes: 0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1 Correlation of Fixed Effects: (Intr) ALTEZZ ALTEZZA -0.155 INTENSITA -0.201 -0.399 I would like to have: 1) an indicator of performarce of my model (is it good the fitness of my model?? 2) a sort of cross-validation 3) information on relative importance of predictors (marginal effects???) Please, help me!!!!! Thanks