Hostname: page-component-74656f9884-8r8nv Total loading time: 0 Render date: 2026-11-09T20:40:39.708Z Has data issue: false hasContentIssue false

The Reliability Factor: Modeling Individual Reliability with Multiple Items from a Single Assessment

Published online by Cambridge University Press:  01 January 2025

Stephen R. Martin*
Affiliation:
University Of California, Davis
Philippe Rast
Affiliation:
University Of California, Davis
*
Correspondence should be made to Stephen R. Martin, Department of Psychology, University of California, Davis, 135 Young Hall, 1 Shields Avenue, Davis, CA 95616, USA. Email: stephenSRMMartin@gmail.com

Abstract

Reliability is a crucial concept in psychometrics. Although it is typically estimated as a single fixed quantity, previous work suggests that reliability can vary across persons, groups, and covariates. We propose a novel method for estimating and modeling case-specific reliability without repeated measurements or parallel tests. The proposed method employs a “Reliability Factor” that models the error variance of each case across multiple indicators, thereby producing case-specific reliability estimates. Additionally, we use Gaussian process modeling to estimate a nonlinear, non-monotonic function between the latent factor itself and the reliability of the measure, providing an analogue to test information functions in item response theory. The reliability factor model is a new tool for examining latent regions with poor conditional reliability, and correlates thereof, in a classical test theory framework.

Information

Type
Theory and Methods
Copyright
Copyright © 2022 The Author(s) under exclusive licence to The Psychometric Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable