star R Documentation

## Student Teacher Achievement Ratio (STAR) project data

### Description

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.

### Usage

data(star)

### Format

A data frame with 26796 observations on the following 18 variables.

id

a factor - student id number

sch

a factor - school id number

gr

grade - an ordered factor with levels K < 1 < 2 < 3

cltype

class type - a factor with levels small, reg and reg+A. The last level indicates a regular class size with a teachers aide.

hdeg

highest degree obtained by the teacher - an ordered factor with levels ASSOC < BS/BA < MS/MA/MEd < MA+ < Ed.S < Ed.D/Ph.D

clad

career ladder position of the teacher - a factor with levels NOT APPR PROB PEND 1 2 3

exp

a numeric vector - the total number of years of experience of the teacher

trace

teacher's race - a factor with levels W, B, A, H, I and O representing white, black, Asian, Hispanic, Indian (Native American) and other

read

the student's total reading scaled score

math

the student's total math scaled score

ses

socioeconomic status - a factor with levels F and N representing eligible for free lunches or not eligible

schtype

school type - a factor with levels inner, suburb, rural and urban

sx

student's sex - a factor with levels M F

eth

student's ethnicity - a factor with the same levels as trace

birthq

student's birth quarter - an ordered factor with levels 1977:1 < ... < 1982:2

birthy

student's birth year - an ordered factor with levels 1977:1982

yrs

number of years of schooling for the student - a numeric version of the grade gr with Kindergarten represented as 0. This variable was generated from gr and does not allow for a student being retained.

tch

a factor - teacher id number

### Details

Details of the original data source and the process of conversion to this representation are given in the vignette.

### Examples

str(star)