Rapid CAT Prototyping with OSCATS: The Open-Source Computerized Adaptive Testing System

Culbertson, Michael J.

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https://hdl.handle.net/2142/27706 Copy

Description

Title

Rapid CAT Prototyping with OSCATS: The Open-Source Computerized Adaptive Testing System

Author(s)

Culbertson, Michael J.

Issue Date

2011-10-04

Keyword(s)

• Computerized Adaptive Testing
• Psychometrics
• Item Response Theory

Abstract

One obstacle to the widespread, rapid development and adoption of CAT is the relative lack of readily available CAT software. Most current CAT systems are either home-grown or proprietary, requiring new users either to be strong programmers or pay licensing fees. A free, off-the-shelf CAT library would allow more developers to enter the CAT field without the redundant burden of writing and debugging computer code for common CAT functions. This presentation describes how to use the new Open-Source Computerized Adaptive Testing System (OSCATS) for rapid prototyping and testing of CAT systems. OSCATS provides code for common CAT routines, which can be mixed-and-matched to customize a CAT with different algorithms and item models for evaluation of CAT systems via simulation. Moreover, OSCATS is extensible, allowing developers to incorporate novel or custom routines easily. OSCATS can be controlled from C, Python, Perl, PHP, Java, and MATLAB. Although OSCATS is still under development, it already has the capability to implement some of the most popular CAT algorithms and models for Item Response Theory and Diagnostic Classification. As a demonstration, an OSCATS-based program will be described to investigate the effect on ability estimation error of answering the first few items correctly or incorrectly under maximum Fisher information, Kullback-Leibler, and a-Stratified item selection.

Type of Resource

text

Language

en

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http://hdl.handle.net/2142/27706

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