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Hello I have a dataset in which I would like to replace 0s with NAs. There is a lot of information on how to replace NAs with 0, but I have struggled to find anything with regards to doing the...

Hi R users, Just a query as to whether lme4 can handle beta-binomial distributions as I read that this was not available. If not, any suggestions on how to handle such a distribution to plot the following model: y...

Hi R Users, Hopefully a very simple solution, but I am stumped nevertheless. I am running glmer in which the output is too large so that not all the correlations are displayed. I expanded the max.print as recommended on...

I want to plot my predictions from a model and use the standard error output as a measure of dispersion as I am unable to calculate confidence intervals with mcmcsamp as I have a binomial distribution. I know that the...

Thanks Jari. Sorted it out now, I hope. I think I was a bit skeptical as to whether it was working as the results were similar to what I previously had without the contrasts. Thanks a million for your time...

Dear All I have a repeated measures design in which abundance was measured repeatedly over 10 months in three treatments (Tortoise A; Tortoise B and control) established in 6 blocks, i.e. crossed fixed effects. My original design incorporated two...

Thanks. I was hoping for a miracle that this had been developed within the last couple of months. I am on the stats learning curve and am not quite sure how flexible to be with regards to distributions. Is quasibinomial...

Dear All, I have done pairwise comparisons of species compositions between three treatments (1 v 2, 1 v 3, and 2 v 3) which were replicated 6 times (i.e. 6 blocks). To avoid multiple testing I have decided to...

Dear All Thanks for the suggestions. Mark's suggestion to specify "corr=FALSE" did the job and removed the reams of correlations that were being outputted from the model and using up all the output space. Thanks Christine --On 06...

Dear R users, Sorry if this question is not applicable to this site. I am having problems analysing unreplicated repeated measures. I calculated food web properties for three treatments over time (10 months). It is unreplicated in that I only...

Dear R users, Many of you may be familiar with my design as I have posted a number of queries before. Having consulted with someone in my department about estimating bias corrected confidence intervals for small sample sizes (rather than...

Dear Emmanuel and Ben Many thanks for your advice. Unfortunately, I don't think that I can offset with log(area), given that each area is the same. My rationale for converting to m2 was to standardise abundances to 1...

Dear R users, I am having a problem with getting zero variance in my lmer models which specify two random effects. Having scoured the help lists, I have read that this could be because my variables are strongly correlated. However...

Sorry I meant mcmcsamp. Page 398, second column, after the table of coefficients estimated. yeah, I have had lots of problems with modeling this data and so was really wondering whether there was a better way to look at it...

Dear Giancarlo, Thank you for very much for your advice. I suspected that may be the case. Do you know if the Zelig package (<http://cran.r-project.org/web/packages/Zelig/vignettes/logit.mixed.pdf>) can accommodate pairing, or...

Thanks. I did try using quasipoisson and a negative binomial error but am unsure of the degree of overdispersion and whether it is simply due to missing values. I am investigating to see if I can replace these missing values...

Dear All Thank you for all your incredibly helpful advice. Having done as suggested by Emmanuel, I have come to the conclusion that there is basically very little variation among my data, which is perhaps not surprising given that I...

Dear Jari and Peter Thanks for the help. It works fine now. Glad it was that simple. :-) I have a number of queries: (1) I am a bit skeptical about the output in that if I run variations of the...

Dear All I am trying to do a repeated measures analysis using lmer and have a number of issues. I have non-orthogonal, unbalanced data. Count data was obtained over 10 months for three treatments, which were arranged into 6...

Thank you for your help. Because I am using glmer with Binomial family I cannot calculate 95% CIs using the mcmcsamp function and have not been able to find a way to do this. Hence my reason to look at...