plot.Bolstad {Bolstad}

R Documentation

Plot method for objects of type Bolstad

Description

A unified plotting method for plotting the prior, likelihood and posterior from any of the analyses in the book

Usage

## S3 method for class 'Bolstad'
plot(
  x,
  overlay = TRUE,
  which = c(1, 3),
  densCols = c("red", "green", "blue")[which],
  legendLoc = "topleft",
  scaleLike = FALSE,
  xlab = eval(expression(x$name)),
  ylab = "",
  main = "Shape of prior and posterior",
  ylim = c(0, max(cbind(x$prior, x$likelihood, x$posterior)[, which]) * 1.1),
  cex = 0.7,
  ...
)

Arguments

x	A S3 object of class Bolstad
overlay	if FALSE then up to three plots will be drawn side-by-side
which	Control which of the prior = 1, likelihood = 2, and posterior = 3, are plots. This is set to prior and posterior by default to retain compatibility with the book
densCols	The colors of the lines for each of the prior, likelihood and posterior
legendLoc	The location of the legend, usually either "topright" or "topleft"
scaleLike	If TRUE, then the likelihood will be scaled to have approximately the same maximum value as the posterior
xlab	Label for x axis
ylab	Label for y axis
main	Title of plot
ylim	Vector giving y coordinate range
cex	Character expansion multiplier
...	Any remaining arguments are fed to the plot command

Details

The function provides a unified way of plotting the prior, likelihood and posterior from any of the functions in the library that return these quantities. It will produce an overlay of the lines by default, or separate panels if overlay = FALSE.

Author(s)

James Curran

Examples

x = rnorm(20,-0.5,1)
## find the posterior density with a N(0,1) prior on mu
b = normnp(x,sigma=1)
plot(b)
plot(b, which = 1:3)
plot(b, overlay = FALSE, which = 1:3)

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