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Dear useRs, I have used using the excellent mgcv package (version 1.7-12) to create a generalized additive model (gam) including random effects - represented with s(...,bs="re") - on the basis of dialect data. My model contains two random...

Dear useRs, This is the first time I post to this list and I would appreciate any help available. I've used the excellent mgcv package for a while now to investigate geographical patterns of language variation, and it has...

Dear useRs, Simon, @Simon: I'll send the data offline. The command summary(...,freq=F) yields the same result as before. Why did the default change from freq=F in version 1.7-13 to freq=T in version 1...

Dear useRs, I ran an additional analysis with another dataset and (logistic regression), but also in this case I obtain very different p-values comparing version 1.7-11 and 1.7-17. Any ideas about this? Which is the...

Dear Simon, I ran an additional analysis using bam (mgcv 1.7-17) with three random intercepts and no non-linearities, and compared these to the results of lmer (lme4). Using bam results in a significant random intercept (even though...

Hi Simon, Thanks for your reply. That is very helpful. However, in the logistic regression example, there also appears to be a large difference in the p-values and estimates when comparing summary(model) # mgcv 1.7-11 summary(model...

Dear useRs, Just to let you know, the results using mgcv 1.7-13 are OK. @Simon: could you perhaps still let me know if the procedure I apply w.r.t. assigning the labels to random slopes and intercepts...

Dear useRs, I reran an analysis with bam (mgcv, version 1.7-17) originally conducted using an older version of bam (mgcv, version 1.7-11) and this resulted in the same estimates, but much lower standard errors (in some...

Dear useRs, I am using mgcv version 1.7-16. When I create a model with a few non-linear terms and a random intercept for (in my case) country using s(Country,bs="re"), the representative line in my...

Dear useRs, I have a question with respect to fitting a non-linearity using gam (mgcv package, version 1.7-16). In a study I'm currently conducting, I'd like to find out if there is a breakpoint after...

Hi Simon, Thanks for your quick reply. I'm now running the model again with mgcv 1.7-13. This might take some time (half a day or so) as the dataset is quite large (112,608 rows). The call...

Dear Simon, Thanks for your concise reply, this is very helpful. With respect to my second question, however, I was not entirely clear - or perhaps I'm misunderstanding your answer. What I meant is: suppose I have a model with...

Dear useRs, I've ran some additional analyses (see below), which strongly suggest the standard errors of the bam (and gam) function are much too low in mgcv version 1.7-17, at least when including an s(X,bs...