R: Shift Plot Between Two Sets of Data

shiftplot {extRemes} | R Documentation

## Shift Plot Between Two Sets of Data

### Description

A shift plot is a plot of the quantiles of a data set y minus those of another data set x against those of x. Includes 95 percent simultaneous confidence bands.

### Usage

    shiftplot(x, y, pch = 20, xlab = "x Quantiles", ylab = "y Quantiles", main = NULL, ...)

### Arguments

`x` | numeric vector of length m.
`y` | numeric vector of length n.
`pch` | Plotting character.
`xlab` | Character string giving abscissa axis label.
`ylab` | Character string giving ordinate axis label.
`main` | Character string giving plot title.
`...` | Other optional arguments to plot function.

### Details

The shift plot is a graph of y_q - x_q vs. x_q, where y_q and x_q denote the quantiles of x and y, resp. 95 percent simultaneous confidence bands are calculated per Doksum and Sievers (1976). The primary usage of this plot is where x is a control group and y is an experimental method; or something similar. For example, x might represent observations, and y might represent climate model output; or some such.

### Value

No value is returned, but a plot is created.

### Author(s)

Peter Guttorp

### References

Doksum, K. A. and Sievers, G. L. (1976) Plotting with confidence: graphical comparisons of two populations. Biometrika, 63, (3), 421–434.

### See Also

`qqplot`, `qqnorm`, `approxfun`

### Examples

    z <- rnorm( 100)
    y <- rexp(30)
    shiftplot( z, y)

    data( ftcanmax)
    shiftplot( y, ftcanmax[,"Prec"])

[Package extRemes version 2.0-9 Index]