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Hello everyone, Suppose I want to fit the same mixed model to a set of response variables and store the results in a single object. Then retrieve the results one by one using an index or some other referencing method...

Hello everyone, I can not find in the documentation how to fit the following model with lmer, any help would be much appreciated: Suppose I have a set of three covariates z1, z2, z3 that I want to fit as...

Hello everyone, I have a questions on refitting models using lmer. Some time ago, I asked about refitting the same model (X,Z,R) to many responses and was pointed at the refit function as a more efficient alternative to...

Hello all, I have a question on using lmer with know variance component ratios: Background: I want to fit a model of the type: y=X b+Z_1 u_1+...+Z_Q u_Q+e, with u_q~N...

Jeff, Why not use the model without the random effect as the null model? JP Jeff Evans wrote: > I'm sure this must have been discussed before, but in searching the archives > I haven't found an answer yet. > > Simple...

Hello all, This is my first post in the list as I just started to use lmer for my routine analyses (side by side with P.Mixed... just for now 8^D ). The following comment caught my attention: > I have...

Hello, I noticed this a wile ago. One thing that occurred to me was to copy to another object before running mcmcsamp, example: obmix0<-obmix where obmix is the lmer object. then do: mcmcsamp(obmix).... For some reason obmix0 gets...

Thanks for the comment John, I should have written that better. I had in mind a very simple CRBD with one grouping factor (treatment) and complete blocks with only one plot per treatment. You are perfectly right, when there are...

Hello, Treating a block effect as random allows recovering inter-block information. In a complete randomized block design (CRBD), treating blocks as fixed or random should yield identical results. In an incomplete block design (incomplete by design or by missing...

Hello Paolo, We are also starting to use lmer for gene expression analysis (genetical genomics too) so here are my thoughts. Having two equivalent parameterizations, I would go with the computationally fastest one (a couple more miliseconds per model, easily...

Hello Christina, Dr. Bates already gave an excelent explanation with some examples were transformed variables are widely accepted. My experience comes from working with gene expression data, where colleagues like to express comparisons as "Fold-change" or ratios. In that...

Hello paolo, sobj<-summary(result), where result is m1a, m1b or m1c. Not that m1c is actually a fixed effects model, and can not be fit with lmer, so you'll need to reconstruct the -2LL from another source. But...