weibullness (version 1.24.1)

ep.plot: Exponential Probability Plot

Description

ep.plot produces a exponential probability plot.

Usage

ep.plot(x, plot.it=TRUE, a, col.line="black", lty.line=1, 
        xlim=NULL, ylim=NULL, main=NULL, sub=NULL, xlab=NULL, ylab="Probability", ...)

Value

A list with the following components:

x

The sorted data

y

-log(1-ppoints(n,a=a))

Arguments

x

a numeric vector of data values. Missing values are allowed.

plot.it

logical. Should the result be plotted?

a

the offset fraction to be used; typically in (0,1). See ppoints.

col.line

the color of the straight line.

lty.line

the line type of the straight line.

xlim

the x limits of the plot.

ylim

the y limits of the plot.

main

a main title for the plot, see also title.

sub

a sub title for the plot.

xlab

a label for the x axis, defaults to a description of x.

ylab

a label for the y axis, defaults to "Probability".

...

graphical parameters.

Author

Chanseok Park

Details

The exponential probability plot is based on taking the logarithm of the exponential cumulative distribution function.

See Also

plot, qqnorm, qqplot, wp.plot, iwp.plot.
bs.plot for the Birnbaum-Saunders probability plot in package bsgof.

Examples

x = rexp(50)
# With cosmetic lines 
ep.plot(x, main="Exponential Probability Plot", col.line="red", lty.line=1, pch=3)
hline = -log(1- c(0.01,(1:9)/10,0.99))
abline( h=hline, col=gray(0.1), lty=3, lwd=0.5 )
abline( v=seq(0, 5,by=0.5), col=gray(0.1), lty=3, lwd=0.5 )