equate_irt_scales: Equate IRT scales using anchor item parameters

In eyeprocess: Harmonize Eye-Tracking, Pupillometry, Biometrics, and Psychometric Process Data

Equate IRT scales using anchor item parameters

Description

Implements mean-sigma, mean-mean, Stocking-Lord, and Haebara linking for dichotomous 2PL-style item parameters. New-form parameters are transformed onto the reference scale using theta_ref = A * theta_new + B.

Usage

equate_irt_scales(
  reference,
  new,
  method = c("stocking-lord", "haebara", "mean-sigma", "mean-mean"),
  theta_grid = seq(-4, 4, length.out = 81)
)

Arguments

reference	Reference-scale parameters or data.
new	New-scale parameters or data.
method	Method used for estimation, linking, or comparison.
theta_grid	Grid of latent-trait values used for evaluation.

Value

An object of class "eye_irt_equating", stored as a named list, with components "A", "B", "method", "transformed", "reference", "new", "equation". It contains equate IRT scales using anchor item parameters and associated metadata or diagnostics needed to interpret the result.

eyeprocess documentation built on Sept. 28, 2026, 5:08 p.m.