<p>a matrix (or data frame, which will be converted to a matrix) containing
only zeroes an ones. NAs are not allowed.</p>

<p>Matrix of tetchoric correlations using the approximation by 
Bonett and Price (2005).</p>

models

A collection of functions useful in learning and practicing IRT,
which can be combined into larger programs. Provides basic CTT analysis,
a simple common interface to the estimation of item
parameters in IRT models for binary responses with three different programs
(ICL, BILOG-MG, and ltm), ability estimation (MLE, BME, EAP, WLE, plausible
values), item and person fit statistics, scaling methods (MM, MS, Stocking-Lord,
and the complete Hebaera method), and a rich array of parametric and
non-parametric (kernel) plots. Estimates and plots Haberman's interaction model
when all items are dichotomously scored.

Ivailo Partchev

irtoys

tet: Approximate tetchoric correlation matrix

Description

Usage

Arguments

Value

References

Examples