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