ltm (version 0.8-9)

plot descript: Descriptive Statistics Plot method

Description

The plot method for descript objects currently works for dichotomous response patterns, and produces the xy-plot of the total score versus the proportion of correct responses for each item.

Usage

## S3 method for class 'descript':
plot(x, items = NULL, includeFirstLast = FALSE, xlab, ylab, \dots)

Arguments

x

an object inheriting from class descript.

items

a numeric vector indicating which items to plot.

includeFirstLast

logical; if TRUE the first and last total scores categories are included.

xlab, ylab

character string or an expression; see title.

...

extra graphical parameters to be passed to matplot().

See Also

descript

Examples

## Descriptives for WIRS data:
dsc <- descript(WIRS)
dsc
plot(dsc, includeFirstLast = TRUE, type = "b", lty = 1, pch = 1:6)
legend("topleft", names(WIRS), pch = 1:6, col = 1:6, lty = 1, bty = "n")