MEdims: Calculate dimensions in mixed-effects
Description
Calculate the dimensions of various arrays used to represent a
mixed-effects model.Usage
MEdims(groups, ncols)
Value
a list of dimensionsNtotal number of observations in the original data.ZXrowsnumber of rows in the ZXy array. This can be
different from N if the condensed linear model has been
decomposed by MEdecomp.ZXcolsnumber of columns in the ZXy array.Qnumber of levels of random effects.StrRowstotal number of rows in the arrays to be stored if
conditional estimates of random effects and fixed effects are to be
calculated.qveca vector of length Q+2 giving the number of columns
in the model matrices for each level of random effects, the fixed
effects and the response.ngrpsa vector of length Q giving the number of groups
at each level of the random effects.DmOffa vector of length Q giving the offsets into the
concatenated relative precision factor arrays.ncolsa vector of length Q giving the number of columns
in the model matrices at each level of random effects.nrota vector of length Q+2 giving the number of columns
to the right of the current level in the ZXy array that must
be rotated in the decomposition.ZXoffa list of vectors of length Q+2 giving the offsets
into the ZXy array for the beginning of the model matrix in
each group at each level.ZXlena list of vectors of length Q+2 giving the lengths
(number of rows) of the model matrix in each group at each level.SToffa list of vectors of length Q+2 giving the offsets
into the stored data array for the beginning of the model matrix in
each group at each level.DecOffa list of vectors of length Q+2 giving the offsets
into the decomposed data array for the beginning of the model matrix in
each group at each level. These offsets differ from SToff
when there are nested random effects. The DecOff entry for
an outer grouping factor points to the beginning of the block and the
SToff entry points to the beginning of the last section of
the block.DecLena list of vectors of length Q+2 giving the
lengths (number of rows) in the block to be decomposed for each
group at each level.