Evaluating math test of students through different item functioning: Who’s taken benefit and harmed?

Abstract

Our study intended to evaluate material on math test in elementary school. This study involved 63 elementary school students in Jakarta. We used a fraction number and geometry test as a parameter to know how strongly the substance of the test items to testing the students ability in performing the math test. The different item functioning (DIF) aspect in Rasch Model was applied to identify the existence of the bias on measurement to the tests that have been performed. The results of this study prove that the quality of the tests is excellent. Unfortunately, the students consistency of answered the test are inadequate. Furthermore, there is 1 item exposed bias on gender. Female students are the group that have benefits and vice versa, male students are a group that is disadvantaged in working on item No. 17 in math test. Differences in ability between male and female students in working on each item on math test is also an interesting focus that we short discussed in this article. These findings suggest that the structure of questions addressed by teachers during math test is unsuitable with students’ abilities and disadvantages students because of poorly recognizable students capacities.