calctheta {lordif} | R Documentation |
Calculates the Expected A Posteriori (EAP) theta and the associated posterior standard deviation (PSD) as standard error estimates.
calctheta(ipar, resp.data, theta, prior.mean = 0, prior.sd = 1)
ipar |
a data frame containing the following columns: a, cb1, cb2,..., cb(maxCat) |
resp.data |
a data frame containing item responses |
theta |
a theta grid (quadrature points) |
prior.mean |
prior mean |
prior.sd |
prior standard deviation |
Calculates EAP theta estimates and PSD standard error estimates based on the input item parameters (ipar) and the item response data (resp.data).
A list object with the components
EAP |
Expected A Posteriori estimates of theta |
SE |
Standard Error estimates |
Not all item responses may be present.
Seung W. Choi <s-choi@northwestern.edu>
Bock, R. D. & Mislevy, R. J. (1982). Adaptive EAP Estimation of Ability in a Microcomputer Environment. Applied Psychological Measurement, 6(4), 431-444.
## Not run: calctheta(ipar,resp.data)