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I would certainly check out a Poisson model with the number of successes as outcome and successes+failures as an offset. Joerg On Sun, Mar 18, 2012 at 11:51 AM, Rolf Turner <r.turner at auckland.ac.nz> wrote...

I just realized that I have sent this only to Mohammed. So here it is to the list: These two model fits should yield the same results. In fact, if we use some simulated data generated by the model yik...

It is not clear to me how your data structure looks like, what your outcome variables are, whether you got reasonable results from separate model fits, what exactly you did by reshaping, and so on. Thus I will only throw...

I have tried to replicate Mohammed's problem using synthetic data and used the parameter estimates from his Stata fit for generating the data. The data has the following notable features: - sample size is rather small: 30 groups with 3...

Joana Martelo asked: "However, do you think that considering year a fixed effect will affect the relationship between the other explanatory variables and the response?" Entering an additional variable in a regression model will always change the effects of other...

Nevertheless, some people try: http://www.kaggle.com/c/cause-effect-pairs Joerg On Mon, Apr 22, 2013 at 4:31 PM, Bert Gunter <gunter.berton at gene.com> wrote: > Inline. > > > On Mon, Apr 22, 2013 at 1:15 PM...

Ben, OP initially posted his problem over at the R-help forum: https://stat.ethz.ch/pipermail/r-help/2012-May/311685.html and so there was some discussion already. Mohammed sent me his data off-list and there does...

Probably the best way of doing this is via simulation. Have a look at chapter 5 of: Bolker, B. 2008. Ecological models and data in R. Princeton Univ. Press, Princeton, NJ. for an introduction and a bunch of examples. Joerg...

Hi everybody, I have a (overdispersed) Poisson GLMM and would like to calculate marginal predictions while taking random effects into account. To do that, I am following a simulation based approach which is briefly described in the technical appendix of...

I apologize for my sloppiness in that I did not mention what lme4 version I was using. It was version 0.999375-42. Joerg On Fri, May 4, 2012 at 7:17 AM, Ben Bolker <bbolker at gmail.com> wrote...

Before checking out other packages, I would first try to figure out the reason(s) for the convergence issues. More often than not the reason is just some trivial issue with the data, but could of course also be due...

---------- Forwarded message ---------- From: Joerg Luedicke <joerg.luedicke at gmail.com> Date: Sat, Dec 10, 2011 at 10:35 AM Subject: Re: [R-sig-ME] MIXED MODEL WITH REPEATED MEASURES To: Erin Ryan <erin at the-ryans.com> On Fri, Dec...

So then let's take this screening-study as an example. Would that contain cross-sectional information on individuals from all ages/cohorts, gathered across 20 years (a)? Or would that be individual trajectories/histories spanning 20 years of time...

I am sorry, I feel I have to back off at this point. I think this concerns a whole research plan/ data analysis design which is beyond the scope of a forum like this for several reasons. All I will...

Some thoughts: 1) In "Case 1" you don't specify a random effect and thus your model would reduce to a simple linear model. I have never tried it but I can imagine that specifying at least one random effect...

Hi Ben and Fredrik, Thanks for the comments and the proof! Next time I will be less hasty in responding... Cheers, Joerg On Mon, Mar 19, 2012 at 3:09 AM, Fredrik Nilsson <laf.nilsson at gmail.com> wrote: > Joerg...