# Tomas

less info
reputation
420
bio website location age member for 2 years, 4 months seen yesterday profile views 251

# 470 Actions

 2d comment when to use PCA in this scenario what you mean by SVD? 2d answered What if a log transformation wipes out significance in regression? 2d comment What if a log transformation wipes out significance in regression? what do you mean by "dummy (treatment)" variables? 2d awarded Excavator Dec10 revised Pseudo R squared formula for GLMs The link is a homepage somewhere, likely to change in the future, so I added author so that the book can be then found easily. Dec10 comment Pseudo R squared formula for GLMs I don't have it in the glm output (family possion or quasipoisson). Dec10 suggested suggested edit on Pseudo R squared formula for GLMs Dec7 comment Modelling a mixed model in JAGS/BUGS I think Marat is close - there could be something with the ifelse. I would recommend to simplify your model to smallest version that doesn't work! This could show you the way. Dec3 comment Mixed effects model validation and selection with lme4::glmer Well, then maybe formulate your question more specifically. This way as you have it now it seems like you are asking what random effects do. Which is pretty basic RTFM question. Dec3 comment Contrast matrix definition This is definitely not true. Did you see the Helmert contrasts for example? Dec3 comment Contrast matrix definition @MichaelMayer great, first step towards the definition! :-) I don't get what you mean by "taking only two values". Dec3 comment Contrast matrix definition Of course it is related, but deriving "what it is" from "what it is needed for" is a detective's job, which shouldn't be needed. That's reverse engineering. Things should be documented. Dec3 comment Confidence interval of RMSE I think you are wrong - he wants CI for RMSE, not $\sigma$. And I want it too :) Dec3 comment SE of RMSE in R Someone posted the same question later. Dec3 comment Confidence interval of RMSE Possible duplicate of SE of RMSE in R Dec3 revised Contrast matrix definition edited title Dec3 comment Contrast matrix definition @ttnphns Sorry but you keep doing what all the docs and webs do: you explain what are contrast matrices used for, without addressing the question what the contrast matrix is. This is the purpose of a definition. Dec2 comment Mixed effects model validation and selection with lme4::glmer the title sounded so well, but the question "what are the key differences to this process using glmer" disappointed me. Very basic, trivial question, google what random effect means. It would be much more interesting to ask how one knows that the random effect improved the model and how to select between various model with or without various random effects. Dec2 comment glmm unbalanced nested random factors "I would like to know what are the effects (repercussions for my model) of having only one replicate per environment in some of the cases" - the question is not clear - effect on WHAT? Dec2 revised Contrast matrix definition added 81 characters in body