heplots (version 0.8-1)

pairs.mlm: Pairwise HE Plots

Description

The function (in the form of an mlm method for the generic pairs function) constructs a ``matrix'' of pairwise HE plots (see heplot) for a multivariate linear model.

Usage

## S3 method for class 'mlm':
pairs(x, variables, type = c("II", "III", "2", "3"), 
  offset.axes = 0.05, digits = getOption("digits") - 1, ...)

Arguments

x

an object of class mlm.

variables

indices or names of the three of more response variables to be plotted; defaults to all of the responses.

type

``type'' of sum-of-squares-and-products matrices to compute; one of "II", "III", "2", or "3", where "II" is the default (and "2" is a synomym).

offset.axes

proportion to extend the axes in each direction; defaults to 0.05.

digits

number of significant digits in axis end-labels; taken from the "digits" option.

...

arguments to pass down to heplot, which is used to draw each panel of the display.

References

Friendly, M. (2006). Data Ellipses, HE Plots and Reduced-Rank Displays for Multivariate Linear Models: SAS Software and Examples Journal of Statistical Software, 17(6), 1-42. http://www.jstatsoft.org/v17/i06/ Friendly, M. (2007). HE plots for Multivariate General Linear Models. Journal of Computational and Graphical Statistics, 16, in press. http://www.math.yorku.ca/SCS/Papers/heplots.pdf

See Also

heplot, heplot3d

Examples

# ANCOVA, assuming equal slopes
rohwer.mod <- lm(cbind(SAT, PPVT, Raven) ~ SES + n + s + ns + na + ss, data=Rohwer)

# View all pairs, with ellipse for all 5 regressors
pairs(rohwer.mod, hypotheses=list("Regr" = c("n", "s", "ns", "na", "ss")))