
Dears lme4 and R users: I'm new to lme4 and starting to explore it. I have two questions on regard to model simplification and hope you can help me. I’m modelling the effect of timber harvesting on the number of individuals left in a forest and using two fixed factors and SITE as random factor with poisson family. My questions: 1.- How do I know a random factor is significant or not. I found very small variance and st dev for a random factor (SITE) and based on that I suppose random effect is not significant, but is there any test to determine it. I have seen some papers where chi square and p-values are shown (Svenning et al 2008 Oecologiqa), but do not know how they are obtained. 2.- If the random factor is not significant can I remove it from the model? and run a simple glm with poisson family? 3.- Can I compare with “anova” the lme4 model against that one from glm? I’ll be very grateful for your help. Mariana 
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