GDAtools (version 1.5)

conc.ellipse: Adds concentration ellipses to a correspondence analysis graph.

Description

Adds concentration ellipses to the individuals factor map of a correspondence analysis.

Usage

conc.ellipse(resmca, var, sel = 1:length(levels(varb)), axes = c(1, 2),
 col = rainbow(length(sel)), pcol = rainbow(length(sel)), pcex = 0.2,
 lty = 1, lwd = 1, tcex = 1, text.lab = TRUE)

Arguments

resmca

object of class 'MCA', 'speMCA', 'csMCA', 'multiMCA' or 'stMCA'

var

supplementary variable to plot

sel

numeric vector of indexes of the categories to plot (by default, ellipses are plotted for every categories)

axes

length 2 vector specifying the components to plot (default is c(1,2))

col

vector of colors for the ellipses of plotted categories (by default, rainbow palette is used)

pcol

vector of colors for the points at the center of ellipses of plotted categories (by default, rainbow palette is used)

pcex

numerical value giving the amount by which points at the center of ellipses should be magnified (default is 0.2)

lty

line type for ellipses (default is 1)

lwd

line width for the ellipses (default is 1)

tcex

numerical value giving the amount by which labels at the center of ellipses should be magnified (default is 0.2)

text.lab

whether the labels at the center of ellipses should be displayed (default is TRUE)

Details

This function has to be used after the cloud of individuals has been drawn.

References

Le Roux B. and Rouanet H., Multiple Correspondence Analysis, SAGE, Series: Quantitative Applications in the Social Sciences, Volume 163, CA:Thousand Oaks (2010).

Le Roux B. and Rouanet H., Geometric Data Analysis: From Correspondence Analysis to Stuctured Data Analysis, Kluwer Academic Publishers, Dordrecht (June 2004).

See Also

plot.speMCA, plot.csMCA, plot.multiMCA, plot.stMCA

Examples

# NOT RUN {
## Performs specific MCA (excluding 'NA' categories) of 'Taste' example data set,
## plots the cloud of categories
## and adds concentration ellipses for gender variable
data(Taste)
mca <- speMCA(Taste[,1:11],excl=c(3,6,9,12,15,18,21,24,27,30,33))
plot(mca,type='i')
conc.ellipse(mca,Taste$Gender)

## Draws a blue concentration ellipse for men only
plot(mca,type='i')
conc.ellipse(mca,Taste$Gender,sel=1,col='blue')
# }