Description

From ICL output, read in estimates of item parameters. Invoked automatically when the model is estimated via irtoys. If that is not the case, file must be a file produced with the write_item_param file command in ICL.

Usage

Arguments

Value

A list with three elements, est, se, vcm for the parameter estimates, their standard errors, and the variance-covariance matrix per item. Because ICL does not compute standard errors, se and vcm will be NULL. est is a matrix with one row per item, and three columns: [,1] item discrimination a, [,2] item difficulty b, and [,3] asymptote c. For the 1PL and 2PL models, all asymptotes are equal to 0; for the 1PL, the discriminations are all equal but not necessarily equal to 1.

Author(s)

Ivailo Partchev