Researchers in educational measurement use Differential Item Functioning (DIF) to examine whether test items are functioning uniquely across subgroups of test participants while taking into account their ability level. DIF is essential for test validity arguments, thus making it a necessary part of validity studies. This study examines DIF across…

The main purpose of this study is to determine the time-dependent learning difficulty of "solving problems that require making four operations with natural numbers" of the sixth grade students. The study, adopting the scanning model, consisted of a total of 140 students, including 69 female and 71 male students at the sixth grade. Data…

The main purpose of this study was to investigate the level of student's achievement in mathematics in Yemen. This study use a sample of 200 male students and 200 female students, chosen from eight government schools on the basis of diversified sampling techniques. A mathematics test which composed of seventy five items that covered geometrical…