[R] Logistic regression model selection with overdispersed/autocorrelated data
renaud.lancelot at gmail.com
Tue Jan 31 09:02:26 CET 2006
If you're not interested in fitting caribou-specific responses, you
can use beta-binomial logistic models. There are several package
available for this purpose on CRAN, among which aod. Because these
models are fitted using maximum-likelihood methods, you can use AIC
(or other information criteria) to compare different models.
2006/1/30, Jesse.Whittington at pc.gc.ca <Jesse.Whittington at pc.gc.ca>:
> I am creating habitat selection models for caribou and other species with
> data collected from GPS collars. In my current situation the radio-collars
> recorded the locations of 30 caribou every 6 hours. I am then comparing
> resources used at caribou locations to random locations using logistic
> regression (standard habitat analysis).
> The data is therefore highly autocorrelated and this causes Type I error
> two ways small standard errors around beta-coefficients and
> over-paramaterization during model selection. Robust standard errors are
> easily calculated by block-bootstrapping the data using "animal" as a
> cluster with the Design library, however I haven't found a satisfactory
> solution for model selection.
> A couple options are:
> 1. Using QAIC where the deviance is divided by a variance inflation factor
> (Burnham & Anderson). However, this VIF can vary greatly depending on the
> data set and the set of covariates used in the global model.
> 2. Manual forward stepwise regression using both changes in deviance and
> robust p-values for the beta-coefficients.
> I have been looking for a solution to this problem for a couple years and
> would appreciate any advice.
> R-help at stat.math.ethz.ch mailing list
> PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
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