normal.and.t.and.power: Construct a power graph based on the NTplot.

In HH: Statistical Analysis and Data Display: Heiberger and Holland

Construct a power graph based on the NTplot.

Description

Construct a power graph based on the NTplot. The exported function powerplot calls NormalAndTPower to construct a power curve or beta curve (operating characteristic curve) (or both) from its argument and catenates it to the original graph. The unexported function NormalAndTPower does the construction.

Usage

powerplot(nt, ...)

## S3 method for class 'NormalAndTplot'
powerplot(nt, power=TRUE, beta=FALSE, ...,
                         hh=if (power && beta) c(6,2,2) else c(6,2))

NormalAndTPower(nt,
                which=c("power","beta"),
                digits=4,
                digits.top.axis=digits, digits.left=digits,
                col.power=attr(nt, "color")["col.power"],
                col.beta=attr(nt, "color")["col.beta"],
                cex.pb.axis=1, cex.left.axis=1, cex.xbar=1,
                lwd.reference=4, lwd.line=2,
                main=which, ...)

Arguments

nt	For the generic powerplot, an object. For the NormalAndTplot method, a "NormalAndTplot" object from NTplot.
power, beta	Logical. If TRUE, then display that graph, else don't display it. Used by powerplot.
which	Which graph is to be displayed? "power" for the power curve, or "beta" for the operating characteristic curve. Used by NormalAndTPower.
...	Additional arguments passed on to methods.
hh	The h argument for resizePanels.
digits.top.axis, digits.left, digits, cex.pb.axis, cex.left.axis, cex.xbar	digits.top.axis is the number of significant digits for the top axis. digits.left is the number of significant digits for the observed power or beta on the left axis. digits is a convenience argument to set both digits.axis and digits.left at the same time. These number is passed to the format function. cex.top.axis is the cex value for the top axis values. cex.left.axis is the cex value for the observed power or beta on the left axis. cex.xbar is the cex value for the horizontal axis.
col.power, col.beta	Colors used for the crosshairs on the power and beta panels. The default values are the colors used for the power and beta regions of the NTplot panel.
lwd.reference, lwd.line	lwd values for the power or beta panel. lwd.line is used for the power curve or beta curve. lwd.reference is used for the crosshairs.
main	Main title for graph.

Value

"trellis" object.

Author(s)

Richard M. Heiberger ([e-mail])

Examples

nt <- NTplot(mean0=2, mean1=4, sd=3, n=20, xlim=c(-.1, 6.1), xbar=3.5)
powerplot(nt)

## Not run: 
tt <- NTplot(mean0=2, mean1=4, sd=3, n=20, xlim=c(-.1, 6.1), xbar=3.5, df=4, distribution.name="t")
powerplot(tt)

ntc <- NTplot(xbar=2, sd=3, n=20, xlim=c(-.1, 4.1), type="confidence",
              alpha.left=.025, alpha.right=.025)
ntc
try(powerplot(ntc))

## End(Not run)

HH documentation built on May 29, 2024, 6:24 a.m.