plotellipses function

Draw confidence ellipses around the categories

Draw confidence ellipses around the categories.

plotellipses(model, keepvar = "all", axes = c(1, 2), means=TRUE, level = 0.95, 
    magnify = 2, cex = 1, pch = 20, pch.means=15, type = c("g","p"), 
    keepnames = TRUE, namescat = NULL, xlim=NULL, ylim=NULL, lwd=1, 
    label="all", autoLab=c("auto","yes","no"), 
        graph.type = c("ggplot","classic"), ...)

Arguments

• model: an object of class MCA or PCA or MFA
• keepvar: a boolean or numeric vector of indexes of variables or a character vector of names of variables. If keepvar is "all", "quali" or "quali.sup" variables which are plotted are all the categorical variables, only those which are used to compute the dimensions (active variables) or only the supplementary categorical variables. If keepvar is a numeric vector of indexes or a character vector of names of variables, only relevant variables are plotted.
• axes: a length 2 vector specifying the components to plot
• means: boolean which indicates if the confidence ellipses are for (the coordinates of) the means of the categories (the empirical variance is divided by the number of observations) or for (the coordinates of) the observations of the categories
• level: the confidence level for the ellipses
• magnify: numeric which control how the level names are magnified. A value of 2 means that the level names have character expansion equal to two times cex
• cex: cf. function par in the graphics package
• pch: plotting character for coordinates, cf. function par in the graphics package
• pch.means: plotting character for means, cf. function par in the graphics package
• type: cf. function xyplot in the lattice package
• keepnames: a boolean or numeric vector of indexes of variables or a character vector of names of variables. If keepnames is TRUE, names of levels are taken from the (modified) dataset extracted from modele, if FALSE trimming names is done. When trimming, names of levels are taken from the (modified) dataset extracted from modele, then, the corresponding number of characters of names of original variables plus 1 is removed. If keepnames is a vector of indexes or names, trimming is done on all variables excepted whose in keepnames
• namescat: a vector giving for each observation the value of categorical variable, each variable are stacked under each other. If NULL, names are taken from the (modified) dataset extracted from modele
• xlim: range for the plotted 'x' values, defaulting to the range of the finite values of 'x'
• ylim: range for the plotted 'y' values, defaulting to the range of the finite values of 'y'
• lwd: The line width, a positive number, defaulting to 1
• label: a list of character for the elements which are labelled (by default, "all", you can use "none", "ind", ind.sup"))
• autoLab: if autoLab="auto", autoLab is equal to "y" if there are less than 50 elements and "no" otherwise; if "y", the labels of the drawn elements are placed in a "good" way (can be time-consuming if many elements), and if "no" the elements are placed quickly but may overlap
• graph.type: a character that gives the type of graph used: "ggplot" or "classic"
• ...: further arguments passed to or from other methods

Returns

Return a graph with the ellipses. If only one variable is chosen, the graph is different.

Author(s)

Pierre-Andre Cornillon, Francois Husson francois.husson@institut-agro.fr

See Also

MCA, PCA

Examples

## Not run:

data(poison)
res.mca = MCA(poison, quali.sup = 3:4, quanti.sup = 1:2)
plotellipses(res.mca)
plotellipses(res.mca,keepvar=3:6)
## End(Not run)

data(decathlon)
res.pca <- PCA(decathlon, quanti.sup = 11:12, quali.sup=13)
plotellipses(res.pca,keepvar=13)