Fitting Linear Mixed-Effects Models Using lme4
TLDR
In this article, a model is described in an lmer call by a formula, in this case including both fixed-and random-effects terms, and the formula and data together determine a numerical representation of the model from which the profiled deviance or the profeatured REML criterion can be evaluated as a function of some of model parameters.Abstract:
Maximum likelihood or restricted maximum likelihood (REML) estimates of the parameters in linear mixed-effects models can be determined using the lmer function in the lme4 package for R. As for most model-fitting functions in R, the model is described in an lmer call by a formula, in this case including both fixed- and random-effects terms. The formula and data together determine a numerical representation of the model from which the profiled deviance or the profiled REML criterion can be evaluated as a function of some of the model parameters. The appropriate criterion is optimized, using one of the constrained optimization functions in R, to provide the parameter estimates. We describe the structure of the model, the steps in evaluating the profiled deviance or REML criterion, and the structure of classes or types that represents such a model. Sufficient detail is included to allow specialization of these structures by users who wish to write functions to fit specialized linear mixed models, such as models incorporating pedigrees or smoothing splines, that are not easily expressible in the formula language used by lmer.read more
Citations
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Global patterns in the effects of predator declines on sea urchins
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Home range establishment and the mechanisms of philopatry among female Bornean orangutans ( Pongo pygmaeus wurmbii ) at Tuanan
Alison M. Ashbury,Erik P. Willems,Sri Suci Utami Atmoko,Fajar Saputra,Carel P. van Schaik,Maria A. van Noordwijk +5 more
TL;DR: It is found that females went through a post-dependence phase of exploration characterized by an increase in range size and day journey length, and then settled into home ranges that overlapped highly with their mothers and other female kin, though they associated preferentially with theirmothers.
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Taxonomic, phylogenetic and functional diversity of understorey plants respond differently to environmental conditions in European forest edges
Karen De Pauw,Camille Meeussen,Sanne Govaert,Pieter Sanczuk,Thomas Vanneste,Markus Bernhardt-Römermann,Kurt Bollmann,Jörg Brunet,Kim Calders,Sara A. O. Cousins,Martin Diekmann,Per-Ola Hedwall,Giovanni Iacopetti,Jonathan Lenoir,Sigrid Lindmo,Anna Orczewska,Quentin Ponette,Jan Plue,Federico Selvi,Fabien Spicher,Hans Verbeeck,Pieter Vermeir,Florian Zellweger,Kris Verheyen,Pieter Vangansbeke,Pieter De Frenne +25 more
TL;DR: In this paper, the relative effects and importance of edaphic, stand and landscape conditions on the diversity metrics of understorey plant communities in deciduous forests across Europe were investigated.
References
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TL;DR: Linear Mixed-Effects and Nonlinear Mixed-effects (NLME) models have been studied in the literature as mentioned in this paper, where the structure of grouped data has been used for fitting LME models.
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