Hostname: page-component-77f85d65b8-pkds5 Total loading time: 0 Render date: 2026-04-18T16:50:01.785Z Has data issue: false hasContentIssue false

A Rating Formulation for Ordered Response Categories

Published online by Cambridge University Press:  01 January 2025

David Andrich*
Affiliation:
The University of Western Australia
*
Requests for reprints should be sent to David Andrich, Department of Education, The University of Western Australia, NEDLANDS, Western Australia, 6009.

Abstract

A rating response mechanism for ordered categories, which is related to the traditional threshold formulation but distinctively different from it, is formulated. In addition to the subject and item parameters two other sets of parameters, which can be interpreted in terms of thresholds on a latent continuum and discriminations at the thresholds, are obtained. These parameters are identified with the category coefficients and the scoring function of the Rasch model for polychotomous responses in which the latent trait is assumed uni-dimensional. In the case where the threshold discriminations are equal, the scoring of successive categories by the familiar assignment of successive integers is justified. In the case where distances between thresholds are also equal, a simple pattern of category coefficients is shown to follow.

Information

Type
Original Paper
Copyright
Copyright © 1978 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