lme4 (version 1.1-13)

plot.lmList4: plots for lmList4 objects

Description

diagnostic and confidence-interval plots for lmList fits

Usage

# S3 method for lmList4
plot(x, form, abline, id, idLabels, grid, …)
# S3 method for lmList4.confint
plot(x, y, order, ...)

Arguments

x

an object inheriting from class lmList, representing a list of lm objects with a common model.

y

ignored: for agreement with generic method

form

an optional formula specifying the desired type of plot. Any variable present in the original data frame used to obtain x can be referenced. In addition, x itself can be referenced in the formula using the symbol ".". Conditional expressions on the right of a | operator can be used to define separate panels in a Trellis display. Default is resid(., type = "pool") ~ fitted(.) , corresponding to a plot of the standardized residuals (using a pooled estimate for the residual standard error) versus fitted values.

abline

an optional numeric value, or numeric vector of length two. If given as a single value, a horizontal line will be added to the plot at that coordinate; else, if given as a vector, its values are used as the intercept and slope for a line added to the plot. If missing, no lines are added to the plot.

id

an optional numeric value, or one-sided formula. If given as a value, it is used as a significance level for a two-sided outlier test for the standardized residuals. Observations with absolute standardized residuals greater than the \(1 - value/2\) quantile of the standard normal distribution are identified in the plot using idLabels. If given as a one-sided formula, its right hand side must evaluate to a logical, integer, or character vector which is used to identify observations in the plot. If missing, no observations are identified.

idLabels

an optional vector, or one-sided formula. If given as a vector, it is converted to character and used to label the observations identified according to id. If given as a one-sided formula, its right hand side must evaluate to a vector which is converted to character and used to label the identified observations. Default is getGroups(x).

grid

an optional logical value indicating whether a grid should be added to plot. Default depends on the type of Trellis plot used: if xyplot defaults to TRUE, else defaults to FALSE.

order

which coefficient to order the results by

…

optional arguments passed to the Trellis plot function.

Details

The plot method for lmList4 objects is copied from that for lmList objects; see plot.lmList for details.

Examples

fm.plm  <- lmList(Reaction ~ Days | Subject, sleepstudy)
## diagnostic plot: standardized residuals vs. fitted
plot(fm.plm,id=0.05)
ci <- confint(fm.plm)
## plot CIs, ordered by slope (coefficient 2)
plot(ci,order=2,ylab="Subject")