predict.TIRTfit: Predict trait scores of Thurstonian IRT models

In thurstonianIRT: Thurstonian IRT Models

Predict trait scores of Thurstonian IRT models

Description

Predict trait scores of Thurstonian IRT models

Usage

## S3 method for class 'TIRTfit'
predict(object, newdata = NULL, ...)

Arguments

object	An object of class TIRTfit.
newdata	Optional TIRTdata object (created via make_TIRT_data) containing data of new persons for which trait scores should be predicted based on the fitted model. If NULL (the default), trait scores are predicted for the persons whose data was used to originally fit the model.
...	Further arguments passed to the underlying methods.

Details

When predicting trait scores of new persons (via newdata), posterior medians of item parameters are used for predictions. This implies that the uncertainty in the new trait scores is underestimated as the uncertainty in the (posterior distribution of) item parameters is ignored.

Value

A data frame with predicted trait scores.

thurstonianIRT documentation built on Aug. 22, 2023, 5:08 p.m.