Re: [R-sig-eco] What is the best way to express the goodness of fit for a model obtained by generalized least squares (using gls function from nlme package)?

2018-01-24 Thread Rob Robinson
A good place to start with all GL(M)M questions is Ben Bolker's FAQ which provides thoughts on many commonly asked questions. In particular http://bbolker.github.io/mixedmodels-misc/glmmFAQ.html#how-do-i-compute-a-coefficient-of-determination-r2-or-an-analogue-for-glmms An approach I have used

[R-sig-eco] What is the best way to express the goodness of fit for a model obtained by generalized least squares (using gls function from nlme package)?

2018-01-24 Thread Diego Podadera
Hi everyone, What is the best way to express the goodness of fit for a model obtained by generalized least squares (using gls function from nlme package)? I don’t want to compare this model with other models, so AIC is not a good choice in this case. Is it right to use the approach proposed by

Re: [R-sig-eco] repeated measures ANOVA and PERMANOVA (does it exist?)

2018-01-24 Thread Steve Brewer
David, Assuming the distance/similarity measure is non-euclidean (e.g., Bray-Curtis), see attached pdf document containing a previous post on this subject. This approach is based on the one that Marti Anderson describes in Primer. Good luck, Steve Stephen Brewer

Re: [R-sig-eco] repeated measures ANOVA and PERMANOVA (does it exist?)

2018-01-24 Thread Tania Bird
Principal response curves would be a good way to go if you have balanced data. My recent paper may be of interest: Bird, TLF et al.. (2017) Shrub Encroachment Effects on Habitat Heterogeneity and Beetle Diversity in a Mediterranean Coastal Dune System. Land Degrad. Develop., 28: 2553–2562. doi:

Re: [R-sig-eco] repeated measures ANOVA and PERMANOVA (does it exist?)

2018-01-24 Thread Zoltan Botta-Dukat
Hi, You also try using principal response curves as suggested in this recent publication: dx.doi.org/10.1002/ecs2.2023 Zoltan 2018.01.24. 15:28 keltezéssel, Pedro Pequeno írta: > Hi, > > you could ordinate your observations first (e.g. using NMDS or PCoA), and > then model the resulting

Re: [R-sig-eco] repeated measures ANOVA and PERMANOVA (does it exist?)

2018-01-24 Thread Pedro Pequeno
Hi, you could ordinate your observations first (e.g. using NMDS or PCoA), and then model the resulting scores using location and time as predictors (if you are interested in estimating their independent effects), or using a repeated-measures Anova or a GLMM with location as random factor to