\HeaderA{star}{Student Teacher Achievment Ratio (STAR) project data}{star}
\keyword{datasets}{star}
\begin{Description}\relax
Data from Tennessee's Student Teacher Achievement Ratio (STAR) project
which was  a large-scale, four-year study of the effect of reduced class size.
\end{Description}
\begin{Usage}
\begin{verbatim}data(star)\end{verbatim}
\end{Usage}
\begin{Format}\relax
A data frame with 26796 observations on the following 18 variables.
\describe{
\item[\code{id}] a factor - student id number
\item[\code{sch}] a factor - school id number
\item[\code{gr}] grade - an ordered factor with levels \code{K} <
\code{1} < \code{2} < \code{3} 
\item[\code{cltype}] class type - a factor with levels \code{small},
\code{reg} and \code{reg+A}.  The last level indicates a regular
class size with a teachers aide. 
\item[\code{hdeg}] highest degree obtained by the teacher - an
ordered factor with levels \code{ASSOC} < \code{BS/BA} <
\code{MS/MA/MEd} < \code{MA+} < \code{Ed.S} < \code{Ed.D/Ph.D} 
\item[\code{clad}] career ladder position of the teacher - a factor
with levels \code{NOT} \code{APPR} \code{PROB} \code{PEND}
\code{1} \code{2} \code{3} 
\item[\code{exp}] a numeric vector - the total number of years of
experience of the teacher
\item[\code{trace}] teacher's race - a factor with levels \code{W},
\code{B}, \code{A}, \code{H}, \code{I} and \code{O} representing
white, black, Asian, Hispanic, Indian (Native American) and other
\item[\code{read}] the student's total reading scaled score
\item[\code{math}] the student's total math scaled score
\item[\code{ses}] socioeconomic status - a factor with levels
\code{F} and \code{N} representing eligible for free lunches or
not eligible
\item[\code{schtype}] school type - a factor with levels
\code{inner}, \code{suburb}, \code{rural} and \code{urban}
\item[\code{sx}] student's sex - a factor with levels \code{M} \code{F}
\item[\code{eth}] student's ethnicity - a factor with the same
levels as \code{trace}
\item[\code{birthq}] student's birth quarter - an ordered factor with
levels \code{1977:1} < \dots < \code{1982:2}
\item[\code{birthy}] student's birth year - an ordered factor with levels \code{1977:1982}
\item[\code{yrs}] number of years of schooling for the student - a
numeric version of the grade \code{gr} with Kindergarten
represented as 0.  This variable was generated from \code{gr} and
does not allow for a student being retained.
\item[\code{tch}] a factor - teacher id number
}
\end{Format}
\begin{Details}\relax
Details of the original data source and the process of conversion to
this representation are given in the vignette.
\end{Details}
\begin{Source}\relax
\url{http://www.heros-inc.org/data.htm}
\end{Source}
\begin{Examples}
\begin{ExampleCode}
str(star)
\end{ExampleCode}
\end{Examples}

