TestResponseFunc {exametrika} | R Documentation |
TRF for IRT
Description
Calculates the expected score across all items on a test for a given ability level (theta) using Item Response Theory. The Test Response Function (TRF) is essentially the sum of the Item Characteristic Curves (ICCs) for all items in the test.
Usage
TestResponseFunc(params, theta)
Arguments
params |
parameter matrix |
theta |
ability parameter |
Details
The Test Response Function computes the expected total score for an examinee with a given ability level (theta) across all items in the test. For each item, the function uses the logistic model with parameters a (discrimination), b (difficulty), c (guessing), and d (upper asymptote).
Value
A numeric vector with the same length as theta, containing the expected total score for each ability level.
[Package exametrika version 1.5.1 Index]