Differential Item Functioning in Grade 8 Math Using Logistic Regression, Mantel-Haenszel and Logical Data Analysis

Abstract

This study identified biased test items through DIF analysis using Logistic Regression and Mantel-Haenszel Statistic. Biases were confirmed using LDA based on FGD’s and interviews with teachers and students. The study made use of test scores from 99 male and 101 female grade 8 students to which 108 students were classified as low ability and 92 as high ability students based on their current English grades. A researcher-constructed and validated Statistics Achievement Test was used as research instrument based on Grades 7 and 8 Philippine K-12 competencies.  The results from the two methods were compared, and it was found that sex and English ability bias exist. LDA reveals that bias favors females and high ability group in English which is associated with their capability of memorization and retention of topics taught procedurally. Recommendations include (1) incorporation of DIF analysis in test development; (2) the use of at least two methods in item bias detection; (3) the conduct of LDA or the qualitative component of DIF analysis is vital in understanding DIF to account for context specificity; and (4) for future research, the need to incorporate classroom observation as basis for LDA in DIF justification.

Keywords: item bias, item bias methods, logical data analysis, confirming bias, DIF

DOI: 10.7176/JEP/10-12-17

Publication date: April 30^th 2019