Validation of task items on a screener for initial algebra
Alistair O'Brien, Máire Ní Ríordáin · Zenodo (CERN European Organization for Nuclear Research) · 2021
A standardised criterion referenced assessment known as a screener has been developed for initial algebra. This screener is a formative assessment which has been designed to be of use to teachers in the second-year Irish post-primary mathematics classroom. This paper outlines the design of the screener as guided by the assessment triangle and the subsequent steps in selecting and validating task items for use on the screener. There are two types of items included - selected response (SR) and constructed response (CR). Classical Test Theory (CTT) is used to analyze the results of the SR task items in terms of item difficulty, discrimination, and functioning distractors. Important construct validity evidence arises from the statistical analyses of the item responses. The results of these analyses inform the presentation and layout of the SR task items on the final draft of the screener to ensure the construct of initial algebra is operationalised fairly.