psychotools (version 0.7-4)

plot.btmodel: Visualizing Bradley-Terry Models

Description

Base graphics plotting function for Bradley-Terry models.

Usage

# S3 method for btmodel
plot(x, worth = TRUE, index = TRUE, names = TRUE,
  ref = TRUE, abbreviate = FALSE, type = NULL, lty = NULL,
  xlab = "Objects", ylab = NULL, ...)

Arguments

x

an object of class "btmodel".

worth

logical. Should worth parameters (or alternatively coefficients on log-scale) be displayed?

index

logical. Should different indexes for different items be used?

names

logical. Should the names for the objects be displayed?

ref

logical. Should a horizontal line for the reference level be drawn? Alternatively, ref can also be numeric or character to employ a reference level different from that stored in x.

abbreviate

logical or numeric. Should object names be abbreviated? If numeric this controls the length of the abbreviation.

type

plot type. Default is "b" if index is TRUE.

lty

line type.

xlab, ylab

x and y axis labels.

...

further arguments passed to plot.

See Also

btmodel

Examples

## data
data("GermanParties2009", package = "psychotools")

## Bradley-Terry model
bt <- btmodel(GermanParties2009$preference)
plot(bt)
plot(bt, worth = FALSE)
plot(bt, index = FALSE)