shadeDens: Add a shaded region to a pdf plot

In dafs: Data Analysis for Forensic Scientists

Add a shaded region to a pdf plot

Description

Useful for shading regions of interest (critical regions perhaps) on a theoretical pdf to illustrate concepts such as P-values.

Usage

shadeDens(x0, x1, dens, col = "lightgrey", n.points  = 200,
         lty = 1,...)

Arguments

x0	A starting x-value for the region to be shaded
x1	An ending x-value for the region to be shaded
dens	A function that calculates the pdf
col	A color for the shaded region
n.points	The number of points to calculate the pdf at over the interval [x0,x1]
lty	Line type
...	Additional arguments to be fed to dens such as degrees of freedom, mean or standard deviation

Details

Adds a filled polygon to an existing pdf plot.

Author(s)

J Curran

Examples

x = seq(-4.5,4.5,by = 0.01)
plot(x, dnorm(x), type = 'l')
x0 = qnorm(0.975)
x1 = 4.5
shadeDens(x0, x1, dnorm)

dafs documentation built on April 11, 2022, 5:06 p.m.