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\encoding{UTF-8}
\name{test_info}
\alias{test_info}
\title{Calculate Test Information For \code{eRm} objects
}
\description{
Calculates the information of a test or a scale as the sum of Samejima's (1969) information for all items.
}
\usage{
test_info(ermobject, theta=seq(-5,5,0.01))
}
\arguments{
\item{ermobject}{An object of class \code{'eRm'}.
}
\item{theta}{Supporting or sampling points on the latent trait.
}
}
\details{The function \code{test_info} calculates the test or scale information of the
whole set of items in the \code{'eRm'} object.
}
\value{
Returns the vector of test information for all values of theta.
}
\references{
Samejima, F. (1969) Estimation of latent ability using a response
pattern of graded scores. \emph{Psychometric Monographs}, \bold{17}.
}
\author{Thomas Rusch}
\seealso{
The function to calculate the item information, \code{\link{item_info}}
and the plot function \code{\link{plotINFO}}.
}
\examples{
res <- PCM(pcmdat)
tinfo <- test_info(res)
plotINFO(res, type="test")
}
|
