lmList {lme4}R Documentation

List of lm Objects with a Common Model

Description

Data is partitioned according to the levels of the grouping factor g and individual lm fits are obtained for each data partition, using the model defined in object.

Usage

lmList(formula, data, level, subset, na.action, pool)

Arguments

formula For lmList, a linear formula object of the form y ~ x1+...+xn | g. In the formula object, y represents the response, x1,...,xn the covariates, and g the grouping factor specifying the partitioning of the data according to which different lm fits should be performed. The grouping factor g may be omitted from the formula, in which case the grouping structure will be obtained from data, which must inherit from class groupedData.
data a data frame in which to interpret the variables named in object.
level an optional integer specifying the level of grouping to be used when multiple nested levels of grouping are present.
subset an optional expression indicating which subset of the rows of data should be used in the fit. This can be a logical vector, or a numeric vector indicating which observation numbers are to be included, or a character vector of the row names to be included. All observations are included by default.
na.action a function that indicates what should happen when the data contain NAs. The default action (na.fail) causes lmList to print an error message and terminate if there are any incomplete observations.
pool an optional logical value that is preserved as an attribute of the returned value. This will be used as the default for pool in calculations of standard deviations or standard errors for summaries.

Value

an object of class lmList which is a list of lm objects with as many components as the number of groups defined by the grouping factor.

See Also

lm

Examples

data(Orthodont)
fm1 <- lmList(distance ~ age | Subject, Orthodont)
fm1

[Package lme4 version 0.6-9 Index]