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.
data(star)A data frame with 26796 observations on the following 18 variables.
ida factor - student id number
scha factor - school id number
grgrade - an ordered factor with levels K <
1 < 2 < 3
cltypeclass type - a factor with levels small,
reg and reg+A. The last level indicates a regular
class size with a teachers aide.
hdeghighest degree obtained by the teacher - an
ordered factor with levels ASSOC < BS/BA <
MS/MA/MEd < MA+ < Ed.S < Ed.D/Ph.D
cladcareer ladder position of the teacher - a factor
with levels NOT APPR PROB PEND
1 2 3
expa numeric vector - the total number of years of experience of the teacher
traceteacher's race - a factor with levels W,
B, A, H, I and O representing
white, black, Asian, Hispanic, Indian (Native American) and other
readthe student's total reading scaled score
maththe student's total math scaled score
sessocioeconomic status - a factor with levels
F and N representing eligible for free lunches or
not eligible
schtypeschool type - a factor with levels
inner, suburb, rural and urban
sxstudent's sex - a factor with levels M F
ethstudent's ethnicity - a factor with the same
levels as trace
birthqstudent's birth quarter - an ordered factor with
levels 1977:1 < … < 1982:2
birthystudent's birth year - an ordered factor with levels 1977:1982
yrsnumber 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.
tcha factor - teacher id number
Details of the original data source and the process of conversion to this representation are given in the vignette.