How to Make an Assessment More Informative and Interpretable Using the Ordered Partition Model

Lee, Yongsang

doi:10.29221/jce.2011.14.3.333

J. Curric. Eval. 2013; 14(3):333-361

pISSN: 1229-1544

DOI: https://doi.org/10.29221/jce.2011.14.3.333

Article

How to Make an Assessment More Informative and Interpretable Using the Ordered Partition Model

Yongsang Lee ¹ ^, ^†

Author Information & Copyright ▼

¹Associate Research Fellow, Korea Institute for Curriculum and Evaluation

^†Corresponding Author : Yongsang Lee

ⓒ Copyright 2011, Korea Institute for Curriculum and Evaluation. This is an Open-Access article distributed under the terms of the Creative Commons Attribution NonCommercial-ShareAlike License (http://creativecommons.org/licenses/by-nc-sa/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Sep 01, 2011 ; Revised: Oct 10, 2011 ; Accepted: 25 10, 2011

Published Online: Nov 30, 2013

ABSTRACT

As an extension of the partial credit model (PCM), the ordered partition model (Wilson, 1992; OPM) is designed for the measurement context in which different strategies might lead to the same score on an assessment. In the diagnostic context, the data would neither be nominal nor completely ordered, and so it may not be suitable for other polytomous item responses models. The OPM, however, does deal with this type of data (Wilson, 1992). This paper demonstrates how the OPM can help make assessments more informative. To help readers understand the OPM, the PCM and its relationship with the OPM is first described, then, the interpretation of OPM parameters is explained by showing the OPM results with two illustrative data sets: the ‘Using Evidence’ data and the ‘PISA 2003 science assessment’ data.