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Not yet, but a similar problem was just reported on r-help (under the slightly more panicky subject "hacked") Phillip Sent from my mobile, please excuse the brevity. ________________________________ From: Ben Bolker <bbolker at gmail.com> Sent: Wednesday, April 18, 2018...

You're fitting a normal/Gaussian LMM to data bounded on [0, 1]. The model assumptions about the residuals simply won't hold for bounded, binomial-like values.? Why not fit a binomial model to the data and then use...

Perhaps because I never had to deal with software that relies on explicit nesting of levels, I find it very hard to follow the level-1 and level-2 terminology. Can you provide an example of the model you're...

Yes, it makes sense. This is what is often called an "item" in the discussion on crossed random effects and leaving it out can distort inferences - see Clark 1974 "Language as a fixed effect fallacy" and more recent work by...

Yes, it makes sense. This is what is often called an "item" in the discussion on crossed random effects and leaving it out can distort inferences - see Clark 1974 "Language as a fixed effect fallacy" and more recent work by...

Hi Sebastian, are you using gamm4? If so, you can extract the GAM object, which if I'm not mistaken is already marginalized over the random effects i.e. is just fixed effects, and just use its plotting functions. model...

lme4 doesn't force a hard nested-crossed distinction and can handle implicit nesting/crossing easily (assuming unique identifiers, which you have), so you don't have to worry about that. The only "problem" I see with your model is...

Dear Fabio, Your example runs fine on my machine, and I have a comparable R and nlme version. Have you tried re-installing nlme and all its dependencies? install.packages("nlme",dependencies=TRUE) Sometimes dependencies can get out of sync...

For psycholinguistics datasets (especially EEG and eye movements), I have noticed that nloptwrap sometimes reports convergence failure when "bobyqa" does not. I think the "problem" is with xtol_abs -- changing maxeval has no impact, but allowing for smaller x-step...

With only three sites, you don't have enough levels to use site as a grouping variable / random effect. Random effects are *variance* components and it doesn't make too much sense to discuss variance with only three group members...

Completely agree with Thierry here. In addition to the usual considerations about the bias-variance tradeoff and partial pooling, you need to have things in one model if you really want to compare them. The Difference Between ?Significant? and ?Not...

Dear Anne, For comparison, here's a GAMM for the same example: # Anne's code first, then library(gamm4) gam.mod <- gamm4(DV ~ s(IV1) + IV2 + IV3, random=~(1|RV1) + (1|RV2), ???????????????? data=df, family=binomial) summary(gam.mod$mer...

Dear Jon, dear Kevin, I suspect Kevin is using lmerTest and not lme4 directly. lmerTest does have a type argument for anova() and defaults to the Satterthwaite ddf approximation. Phillip Sent from my mobile, please excuse the brevity. ________________________________ Von: "Fox...

By only using one group, you're changing the amount of pooling going on, which affects shrinkage and the bias-variance / over- vs. underfitting tradeoff. When you fit a model to a subset, it will generally be better at describing...

On 18/2/19 10:19 pm, Ben Bolker wrote: > Agree with everything said here. A few super-low-tech partial > solutions ... > > Others may disagree, but 5000 sims seems pretty extreme for estimating > power (which is after all never better...

Uh ... part of my problem is the term "AUC". Without some very explicit note to the contrary, AUC on a stats forum often refers to a cumulative probability or the Receiver Operating Characteristic (ROC AUC). Remember, we're doing this...

I'll do it myself when I get the chance in the next day or so. :-) Phillip ________________________________ From: Luca Danieli <mr.lucedan at hotmail.it> Sent: Thursday, January 11, 2018 10:26 AM To: Alday, Phillip; r-sig-mixed-models...

I don't think this set of questions was ever addressed in any of the subsequent threads on this or other forums .... and so I'll give you a quick non answer of bullet points: * "significance" should not be the...

I'm replying to the last email in the thread, but I'm addressing several issues raised along the way: * I'm not sure you should call it a _likelihood_ ratio test for REML fitted models given that REML isn...

Hi Henrik, hi Thomas, There is one small additional footnote to add to the Type-II/Type-III comparison: Type-II tests respect the principle of marginality, while Type-III tests do not. This is discussed somewhat in John Fox...