Re: [R] glmer with non integer weights

2010-04-23 Thread Kay Cichini
hello, krebs (1995) states MH as prob., but yes it's rather a ratio of probs. at each site i had 4 blocks with 2 treatments (treat vs. control) - after treating i looked for similarity between each of those pairs. it is of interest if changes in similarity due to treatment differ between

Re: [R] glmer with non integer weights

2010-04-22 Thread Emmanuel Charpentier
Sorry for this late answer (I've had a seriously nonmaskable interrupt). Since I have technical questions not related to R, I take the liberty to follow this up by e-mail. I might post a followup summary if another R problem arises... Emmanuel

Re: [R] glmer with non integer weights

2010-04-20 Thread Kay Cichini
hello, it's the Morisita Horn Index, which is an ecological index for similarity between two multivariate objects (vegetation samples with species and its abundance) where a value of one indicates completely same relative importance of species in both samples and 0 denotes total absence of any

Re: [R] glmer with non integer weights

2010-04-19 Thread Kay Cichini
hi emmanuel, thanks a lot for your extensive answer. do you think using the asin(sqrt()) transf. can be justified for publishing prurpose or do i have to expect criticism. naivly i excluded that possibility, because of violated anova-assumptions, but if i did get you right the finite range

Re: [R] glmer with non integer weights

2010-04-19 Thread Emmanuel Charpentier
Le lundi 19 avril 2010 à 03:00 -0800, Kay Cichini a écrit : hi emmanuel, thanks a lot for your extensive answer. do you think using the asin(sqrt()) transf. can be justified for publishing prurpose or do i have to expect criticism. Hmmm ... depends of your reviewers. But if an half-asleep

Re: [R] glmer with non integer weights

2010-04-18 Thread Emmanuel Charpentier
Le vendredi 16 avril 2010 à 00:15 -0800, Kay Cichini a écrit : thanks thierry, i considered this transformations already, but variance is not stabilized and/or normality is neither achieved. i guess i'll have to look out for non-parametrics? Or (maybe) a model based on a non-Gaussian

Re: [R] glmer with non integer weights

2010-04-18 Thread Emmanuel Charpentier
Addendum to my previous answer : In that special case, the limited range of the asin(sqrt()) transformation, which is a shortcoming, turns out to be useful. The fixed-effect doefficients seem semi-reasonable (except for stageB) : (sin(coef(lm(asin(sqrt(MH.Index))~0+stage, data=similarity^2

Re: [R] glmer with non integer weights

2010-04-16 Thread Kay Cichini
thanks thierry, i considered this transformations already, but variance is not stabilized and/or normality is neither achieved. i guess i'll have to look out for non-parametrics? best regards, kay -- View this message in context:

Re: [R] glmer with non integer weights

2010-04-16 Thread Kay Cichini
thank you thomas for the helpful hint! yours, kay -- View this message in context: http://n4.nabble.com/glmer-with-non-integer-weights-tp1837179p1965827.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing

Re: [R] glmer with non integer weights

2010-04-13 Thread ONKELINX, Thierry
answer can be extracted from a given body of data. ~ John Tukey -Oorspronkelijk bericht- Van: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] Namens Kay Cichini Verzonden: maandag 12 april 2010 16:12 Aan: r-help@r-project.org Onderwerp: [R] glmer with non integer

Re: [R] glmer with non integer weights

2010-04-13 Thread Kay Cichini
thanks thierry, my problem is that the index is a propability which is not derived from incidents per nr. of observations, thus i don't have those numbers but only the plain index, which i want to test. greatings, kay -- View this message in context:

Re: [R] glmer with non integer weights

2010-04-13 Thread ONKELINX, Thierry
: dinsdag 13 april 2010 13:37 Aan: r-help@r-project.org Onderwerp: Re: [R] glmer with non integer weights thanks thierry, my problem is that the index is a propability which is not derived from incidents per nr. of observations, thus i don't have those numbers but only the plain index, which i

Re: [R] glmer with non integer weights

2010-04-13 Thread Thomas Lumley
On Tue, 13 Apr 2010, ONKELINX, Thierry wrote: So your respons variable behaves like a continuous variable except that is range is limited to the 0-1 interval. In such a case I would transform the respons variable (e.g. logit, sqrt(arcsin())) and use a gaussian model. A logit-Normal has

[R] glmer with non integer weights

2010-04-12 Thread Kay Cichini
hello, i'd appreciate help with my glmer. i have a dependent which is an index (MH.index) ranging from 0-1. this index can also be considered as a propability. as i have a fixed factor (stage) and a nested random factor (site) i tried to model with glmer. i read that it's possible to use a