lsat {SMIR} | R Documentation |
The original dataset consists of responses from 1,000 subjects to five dichotomous items from section 6 of the LSAT exam. The version here is presented as frequencies of unique patterns of responses. The data is from Bock and Lieberman 1970.
data(lsat)
A data frame with 32 observations on the following 7 variables. The
variable wt7
represents the number with each pattern.
y1
y2
y3
y4
y5
wt6
wt7
See p.547 in SMIR
Bock, R. and Leiberman, M. (1970), "Fitting a response model for a $n$ dichotomously scored items." Psychometrika, 35, 179–197.
Bock, R. D. and Aitkin, M. (1981). "Marginal maximum likelihood estimation of item parameters: An application of an EM algorithm." Pyschometrika, 46, 443–459.
data(lsat)