What are the advantages of nlme compared to lme4?
The main advantage of nlme relative to lme4 is a user interface for fitting models with structure in the residuals (var- ious forms of heteroscedasticity and autocorrelation) and in the random-effects covariance matrices (e.g., compound symmetric models).
Which is the last recommendation in lme4 glmer?
The last recommendation (i.e., optimizers) has worked for me in the past: e.g., add control=glmerControl (optimizer=”bobyqa”,optCtrl=list (maxfun=2e5)) to your glmer call. The correlation of fixed effects in your last output suggests that there is a problem of multicollinearity.
Is there a mixed effects model using glmer?
My data set has a binomial dependent variable, 3 categorical fixed effects and 2 categorical random effects (item and subject). I am using a mixed effects model using glmer (). Here is what I entered in R:
What are the performance capabilities of the lmer function?
the performance capabilities of lmer. 1.3. High-level modular structure The lmer function is composed of four largely independent modules. In the first module, a mixed-model formula is parsed and converted into the inputs required to specify a linear mixed model (Section 2). The second module uses these inputs to construct an R function which
How to fit nonlinear mixed effect models in lme4?
The functions SSbiexp , SSlogis, etc, see selfStart, provide this (and more). Alternatively, you can use deriv () to automatically produce such functions or expressions. an optional data frame containing the variables named in formula.
Can a piecewise growth model be extended in LME?
Fitting this model is straight-forward in lmer and more complicated in lme. We could extend the two-part piecewise growth model to allow for non-linear change during one or both of the pieces. As an example, I’ll cover extending the model to allow for quadratic change during piece 1.
Which is the best model to fit for nlmer?
Fit nonlinear mixed-effects models, such as those used in population pharmacokinetics. Adaptive Gauss-Hermite quadrature ( nAGQ > 1) is not currently implemented for nlmer. Several other methods, such as simulation or prediction with new data, are unimplemented or very lightly tested.