Calculate lmeStruct Residuals

DESCRIPTION:

The residuals at level i are obtained by subtracting the fitted values at that level from the response vector. The fitted values at level i are obtained by adding together the population fitted values (based only on the fixed effects estimates) and the estimated contributions of the random effects to the fitted values at grouping levels less or equal to i.

USAGE:

residuals(object, levels, lmeFit, conLin) 

REQUIRED ARGUMENTS:

object
an object inheriting from class lmeStruct, representing a list of linear mixed-effects model components, such as reStruct, corStruct, and varFunc objects.

OPTIONAL ARGUMENTS:

level
an optional integer vector giving the level(s) of grouping to be used in extracting the residuals from object. Level values increase from outermost to innermost grouping, with level zero corresponding to the population fitted values. Defaults to the highest or innermost level of grouping.
lmeFit
an optional list with components beta and b containing respectively the fixed effects estimates and the random effects estimates to be used to calculate the residuals. Defaults to attr(object, "lmeFit").
conLin
an optional condensed linear model object, consisting of a list with components "Xy", corresponding to a regression matrix ( X) combined with a response vector ( y), and "logLik", corresponding to the log-likelihood of the underlying lme model. Defaults to attr(object, "conLin").

VALUE:

if a single level of grouping is specified in level, the returned value is a vector with the residuals at the desired level; else, when multiple grouping levels are specified in level , the returned object is a matrix with columns given by the residuals at different levels. NOTE: This method function is primarily used inside the lme function.

REFERENCES:

Bates, D.M. and Pinheiro, J.C. (1998) "Computational methods for multilevel models" available in PostScript or PDF formats at http://nlme.stat.wisc.edu

SEE ALSO:

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