MODEL ANALYSIS AND MODEL CREATION: CAPTURING THE TASK-MODEL STRUCTURE OF QUANTITATIVE ITEM DOMAINS

Abstract

This study focuses on the relationship between item modeling and evidence-centered design (ECD); it considers how an appropriately generalized item modeling software tool can support systematic identification and exploitation of task-model variables, and then examines the feasibility of this goal, using linear-equation items as a test case. The first half of the study examines task-model structures for linear equations and their relevance to item difficulty within ECD. The second half of the study presents prototype software, a Model Creator system for pure math items, designed to partially automate the creation of variant item models reflecting different combinations of task-model variables. The prototype is applied to linear equations but is designed to generalize over a range of pure mathematical content types.