[R-sig-ME] Partial effects in mixed models

[v_coudrain at voila.fr]

Thank you very much, I'll read the article. I knew about structural equation modelling in the software AMOS (SPSS) but it is not very flexible regarding 
distributions.
Best wishes


> Message du 01/03/13 à 15h32
> De : "Thompson,Paul" 

> A : "Steven J. Pierce" 
, "v_coudrain at voila.fr" , "r-sig-mixed-models at r-project.org" 
> Copie à : 
> Objet : RE: [R-sig-ME] Partial effects in mixed models
> 
> Take a look at
> 
> @ARTICLE{Nakagawa-2012-1,
> author = {Nakagawa, S. and Schielzeth, H.},
> title = {A general and simple method for obtaining R$^2$ from generalized
> linear mixed-effects models},
> journal = {Meth. Ecol. Evol.},
> year = {2012},
> pages = {1-120},
> doi = {10.1111/j.2041-210x.2012.00251.x},
> owner = {THOMPSOP},
> timestamp = {2012.12.16}
> }
> They discuss using residuals.
> 
> -----Original Message-----
> From: r-sig-mixed-models-bounces at r-project.org [mailto:r-sig-mixed-models-bounces at r-project.org] On Behalf Of Steven J. Pierce
> Sent: Friday, March 01, 2013 7:34 AM
> To: v_coudrain at voila.fr; r-sig-mixed-models at r-project.org
> Subject: Re: [R-sig-ME] Partial effects in mixed models
> 
> It is my understanding that each coefficient in a model with multiple predictors reflects the effect of that predictor conditional on the set of other predictors 
included in the model. Isn't that exactly what you're trying to obtain? 
> 
> If you want to explicitly model the effects of both predictors on the response and simultaneously model the correlation between those predictors, you could 
switch over to using a multilevel structural equation model. Mplus (a commercial software package) allows you to use Poisson response variables in such 
models. There may also be R packages that also allow such models, but I have not really looked to verify that.
> 
> 
> Steven J. Pierce, Ph.D. 
> Associate Director
> Center for Statistical Training & Consulting (CSTAT) Michigan State University
> E-mail: pierces1 at msu.edu
> Web: http://www.cstat.msu.edu 
> 
> -----Original Message-----
> From: v_coudrain at voila.fr [mailto:v_coudrain at voila.fr]
> Sent: Friday, March 01, 2013 6:35 AM
> To: Steven J. Pierce; r-sig-mixed-models at r-project.org
> Subject: RE: [R-sig-ME] Partial effects in mixed models
> 
> Thank you. My concern was that the model with both variables within may not be optimal because both variables are correlated and I would like to know if the 
second variable has a "pure" effect on the response variable that is independent from the effect of the first variable. Since I have a generalized mixed model 
with poisson distribution, the statistics are based on Chi test and not F tests and I think that these tests are not sequential like in anova. Am I correct? 
> 
> Best
> 
> 
> > Message du 01/03/13 à 03h23
> > De : "Steven J. Pierce" 
> 
> > A : v_coudrain at voila.fr, r-sig-mixed-models at r-project.org Copie à :
> > Objet : RE: [R-sig-ME] Partial effects in mixed models
> > 
> > Why not just run a model with both predictors instead? See King (1986) 
> > for one perspective on why extracting the residuals to use as the 
> > dependent variable in
> another model is sub-optimal. That paper is about plain old OLS regression, but I suspect it still is applicable logic. 
> > 
> > King, G. (1986). How not to lie with statistics: Avoiding common mistakes in quantitative political science. American Journal of Political Science, 30(3), 666-
687.
> > 
> > 
> > Steven J. Pierce, Ph.D. 
> > Associate Director
> > Center for Statistical Training & Consulting (CSTAT) Michigan State 
> > University
> > E-mail: pierces1 at msu.edu
> > Web: http://www.cstat.msu.edu
> > 
> > 
> > -----Original Message-----
> > From: v_coudrain at voila.fr [mailto:v_coudrain at voila.fr]
> > Sent: Thursday, February 28, 2013 11:25 AM
> > To: r-sig-mixed-models at r-project.org
> > Subject: [R-sig-ME] Partial effects in mixed models
> > 
> > Dear all,
> > 
> > I would like to test the effect of an explanatory variable after 
> > removing the effect of another one. I thought about calculating the 
> > model with the first explanatory variable only, then take the model 
> > residuals and use the residuals as response variable to test the 
> > effect of the second explanatory variable. However, I do not know if 
> > this is possible for a model containing random effects. Maybe it 
> > doesn't make sense anyway, but if it is possible, should I include the 
> > random effects in
> the 
> > second model (residuals as response variable) or not, since variance explained by random effects should also have been accounted for in the first model?
> > 
> > Thank you for your help
> > 
> > Valérie
> > ___________________________________________________________
> > Alain Delon horrifié et dévasté de tristesse ! Mais pour quelle raison 
> > ? À lire sur Voila.fr 
> > http://people.voila.fr/people/actu-stars/tv-cine-musique/alain-delon-
> horrifie-et-devaste-de-tristesse-repond-a-son-fils-people_9663.html
> > 
> > 
> > 
> > 
> 
> ___________________________________________________________
> News TV : Valérie Damidot annonce la fin de son émission D&Co ! À lire sur Voila.fr http://people.voila.fr/people/actu-stars/personnalites/valerie-damidot-
annonce-la-fin-de-d-co-people_9679.html
> 
> _______________________________________________
> R-sig-mixed-models at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-sig-mixed-models
> -----------------------------------------------------------------------
> Confidentiality Notice: This e-mail message, including any attachments,
> is for the sole use of the intended recipient(s) and may contain
> privileged and confidential information. Any unauthorized review, use,
> disclosure or distribution is prohibited. If you are not the intended
> recipient, please contact the sender by reply e-mail and destroy
> all copies of the original message.
> 

___________________________________________________________
News TV : Valérie Damidot annonce la fin de son émission D&Co ! À lire sur Voila.fr http://people.voila.fr/people/actu-stars/personnalites/valerie-damidot-annonce-la-fin-de-d-co-people_9679.html