swh:1:snp:813359ba77493c9d5dd1abad9a1f53490a8abf57
Tip revision: b1d73278a87bcb94c00cedbbaff294f96e71bbf0 authored by Torsten Hothorn on 13 April 2010, 00:00:00 UTC
version 1.0-11
version 1.0-11
Tip revision: b1d7327
expectation-methods.Rd
\name{expectation-methods}
\docType{methods}
\alias{expectation}
\alias{expectation-methods}
\alias{expectation,IndependenceTest-method}
\alias{expectation,IndependenceLinearStatistic-method}
\alias{covariance}
\alias{covariance-methods}
\alias{covariance,CovarianceMatrix-method}
\alias{covariance,IndependenceTest-method}
\alias{covariance,IndependenceLinearStatistic-method}
\alias{variance}
\alias{variance-methods}
\alias{variance,Variance-method}
\alias{variance,CovarianceMatrix-method}
\alias{variance,IndependenceTest-method}
\alias{variance,IndependenceLinearStatistic-method}
\title{ Extract the Expectation and Variance / Covariance of Linear Statistics }
\description{
Extracts the conditional expectation and covariance
for linear statistics from objects inheriting from "IndependenceTest".
}
\usage{
expectation(object, ...)
covariance(object, ...)
variance(object, ...)
}
\arguments{
\item{object}{an object inheriting from class
\code{\link{IndependenceTest-class}}.}
\item{\dots}{further arguments (currently ignored).}
}
\section{Methods}{
\describe{
\item{expectation}{extracts the expectation of the linear
statistic of \code{object}.}
\item{covariance}{extracts the covariance of the linear
statistic of \code{object}.}
\item{variance}{extracts the variance of the linear
statistic of \code{object}.}
}
}
\examples{
df <- data.frame(y = gl(3, 2), x = gl(3, 2)[sample(1:6)])
### Cochran-Mantel-Haenzel Test
ct <- cmh_test(y ~ x, data = df)
### the linear statistic, i.e, the contingency table
l <- statistic(ct, type = "linear")
l
### expectation
El <- expectation(ct)
El
### covariance
Vl <- covariance(ct)
Vl
### the standardized contingency table (hard way)
(l - El) / sqrt(variance(ct))
### easy way
statistic(ct, type = "standardized")
}
\keyword{methods}