The validity of item bias techniques with math word problems

Abstract

Item bias research has compared methods empirically using both computer simulation with known amounts of bias and real data with unknown amounts of bias. This study extends previous research by "planting" biased items in the realistic context of math word problems. "Biased" items are those in which the reading level is too high for a group of students so that the items are unable to assess the students’ math knowledge. Of the three methods assessed (Angoff’s transformed difficulty, Camilli’s full chi-square, and Linn and Harnisch’s item response theory, IRT, approach), only the IRT approach performed well. Removing the biased items had a minor effect on the validity for the minority group.