iwp.plot: Inverse Weibull Probability Plot

In weibullness: Goodness-of-Fit Test for Weibull Distribution (Weibullness)

Inverse Weibull Probability Plot

Description

iwp.plot produces an inverse Weibull probability plot.

Usage

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

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.

Details

The inverse Weibull probability plot is based on taking the logarithm of the inverse Weibull cumulative distribution function twice.

Value

A list with the following components:

x	The sorted data
y	-log(-log(ppoints(n,a=a)))

Author(s)

Chanseok Park

See Also

plot, qqnorm, qqplot, wp.plot.

Examples

 
x = c(0.38, 0.41, 1.2, 0.52, 0.69, 0.89, 0.67, 1.59, 0.55, 0.59)
iwp.plot( x )

# With cosmetic lines 
iwp.plot(x, main="Inverse Weibull Probability Plot", col.line="red", 
        xlab="Lifetimes of bearings", lty.line=1, pch=3)
hline = -log(-log( c( (1:5)/100, (1:9)/10)  ))
abline( h=hline, col=gray(0.1), lty=3, lwd=0.5 )
abline( v=  seq(0, 2,by=0.1), col=gray(0.1), lty=3, lwd=0.5 )

weibullness documentation built on May 29, 2024, 1:27 a.m.