HH (version 2.1-23)

F.curve: plot a chisquare or a F-curve.

Description

Plot a chisquare or a F-curve. Shade a region for rejection region or do-not-reject region. F.observed and chisq.observed plots a vertical line with arrowhead markers at the location of the observed xbar and outlines the area corresponding to the p-value.

Usage

F.setup(df1=1,
        df2=Inf,
        ncp=0,
        log.p=FALSE,
        xlim.in=c(0, 5),
        ylim.in=range(c(0, 1.1*df.intermediate(x=seq(.5,1.5,.01), df1=df1, df2=df2, ncp=ncp, log=log.p))),
        main.in=main.calc,
        ...)
F.curve(df1=1,
        df2=Inf,
        ncp=0,
        log.p=FALSE,
        alpha=.05,
        critical.values=f.alpha,
        f=seq(0, par()$usr[2], length=109),
        shade="right", col=par("col"),
        axis.name="f",
        ...)
F.observed(f.obs, col="green",
           df1=1,
           df2=Inf,
           ncp=0,
           log.p=FALSE,
           axis.name="f")
chisq.setup(df=1,
           ncp=0,
           log.p=FALSE,
           xlim.in=c(0, qchisq.intermediate(p=1-.01, df=df, ncp=ncp, log.p=log.p)),
           ylim.in=range(c(0, 1.1*dchisq.intermediate(x=seq(max(0.5,df-2),df+2,.01), df=df, ncp=ncp, log=log.p))),
           main.in=main.calc,
           ...)
chisq.curve(df=1,
            ncp=0,
            log.p=FALSE,
            alpha=.05,
            critical.values=chisq.alpha,
            chisq=seq(0, par()$usr[2], length=109),
            shade="right", col=par("col"),
            axis.name="chisq",
            ...)
chisq.observed(chisq.obs, col="green",
               df=1,
               ncp=0,
               log.p=FALSE,
               axis.name="chisq")

Arguments

xlim.in, ylim.in

Initial settings for xlim, ylim. The defaults are calculated for the degrees of freedom.

df, df1, df2, ncp, log.p

Degrees of freedom, non-centrality parameter, probabilities are given as log(p). See pchisq and pf.

alpha

Probability of a Type I error. alpha is a vector of one or two values. If one value, it is the right alpha. If two values, they are the c(left.alpha, right.alpha).

critical.values

Critical values. Initial values correspond to the specified alpha levels. A scalar value implies a one-sided test on the right side. A vector of two values implies a two-sided test.

main.in

Main title.

shade

Valid values for shade are "right", "left", "inside", "outside", "none". Default is "right" for one-sided critical.values and "outside" for two-sided critical values.

col

color of the shaded region and the area of the shaded region.

f,chisq

Values used to draw curve. Replace them if more resolution is needed.

f.obs, chisq.obs

Observed values of statistic. p-values are calculated for these values.

axis.name

Axis name.

...

Other arguments which are ignored.

Examples

old.omd <- par(omd=c(.05,.88, .05,1))
chisq.setup(df=12)
chisq.curve(df=12, col='blue')
chisq.observed(22, df=12)
par(old.omd)

old.omd <- par(omd=c(.05,.88, .05,1))
chisq.setup(df=12)
chisq.curve(df=12, col='blue', alpha=c(.05, .05))
par(old.omd)

old.omd <- par(omd=c(.05,.88, .05,1))
F.setup(df1=5, df2=30)
F.curve(df1=5, df2=30, col='blue')
F.observed(3, df1=5, df2=30)
par(old.omd)

old.omd <- par(omd=c(.05,.88, .05,1))
F.setup(df1=5, df2=30)
F.curve(df1=5, df2=30, col='blue', alpha=c(.05, .05))
par(old.omd)