lme4: mkReTrms – R documentation

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mkReTrms

Make Random Effect Terms: Create Z, Lambda, Lind, etc.

Description

From the result of findbars applied to a model formula and the evaluation frame fr, create the model matrix Zt, etc, associated with the random-effects terms.

Usage

mkReTrms(bars, fr, drop.unused.levels=TRUE,
                     reorder.terms=TRUE,
                     reorder.vars=FALSE)

Arguments

`bars`	a list of parsed random-effects terms
`fr`	a model frame in which to evaluate these terms
`drop.unused.levels`	(logical) drop unused factor levels? (experimental)
`reorder.terms`	arrange random effects terms in decreasing order of number of groups (factor levels)?
`reorder.vars`	arrange columns of individual random effects terms in alphabetical order?

Value

a list with components

`Zt`	transpose of the sparse model matrix for the random effects
`theta`	initial values of the covariance parameters
`Lind`	an integer vector of indices determining the mapping of the elements of the `theta` vector to the `"x"` slot of `Lambdat`
`Gp`	a vector indexing the association of elements of the conditional mode vector with random-effect terms; if `nb` is the vector of numbers of conditional modes per term (i.e. number of groups times number of effects per group), `Gp` is `c(0,cumsum(nb))` (and conversely `nb` is `diff(Gp)`)
`lower`	lower bounds on the covariance parameters
`Lambdat`	transpose of the sparse relative covariance factor
`flist`	list of grouping factors used in the random-effects terms
`cnms`	a list of column names of the random effects according to the grouping factors
`Ztlist`	list of components of the transpose of the random-effects model matrix, separated by random-effects term

Examples

data("Pixel", package="nlme")
mform <- pixel ~ day + I(day^2) + (day | Dog) + (1 | Side/Dog)
(bar.f <- findbars(mform)) # list with 3 terms
mf <- model.frame(subbars(mform),data=Pixel)
rt <- mkReTrms(bar.f,mf)
names(rt)

lme4

Linear Mixed-Effects Models using 'Eigen' and S4

v1.1-26

GPL (>= 2)

Authors

Douglas Bates [aut] (<https://orcid.org/0000-0001-8316-9503>), Martin Maechler [aut] (<https://orcid.org/0000-0002-8685-9910>), Ben Bolker [aut, cre] (<https://orcid.org/0000-0002-2127-0443>), Steven Walker [aut] (<https://orcid.org/0000-0002-4394-9078>), Rune Haubo Bojesen Christensen [ctb] (<https://orcid.org/0000-0002-4494-3399>), Henrik Singmann [ctb] (<https://orcid.org/0000-0002-4842-3657>), Bin Dai [ctb], Fabian Scheipl [ctb] (<https://orcid.org/0000-0001-8172-3603>), Gabor Grothendieck [ctb], Peter Green [ctb] (<https://orcid.org/0000-0002-0238-9852>), John Fox [ctb], Alexander Bauer [ctb], Pavel N. Krivitsky [ctb, cph] (<https://orcid.org/0000-0002-9101-3362>, shared copyright on simulate.formula)

Initial release