The Impact of the Number of Distractors in Multiple-choice Test Items on the Psychometric Characteristics of the Items and Item Information Function According to the Two-Parameter Logistic Model in the Item Response Theory

Abstract

The aim of the current study was to identify the impact of the number of distractors in multiple-choice test items on the psychometric characteristics of the test items and the item information function according to the two-parameter logistic model in the Item Response Theory (IRT). To answer the study questions, an achievement test was built covering all school tests course that measures teachers' degree of knowledge to build school tests. The test consisted of (42) items and was of 3 different forms varying in the number of options. The study sample consisted of 356 male and female teachers from Ma'an governorate and Wadi al-Sair district and was selected in a simple random manner. The statistical program (SPSS) and the (Bilog-mg3) program were used to analyse the responses of the study sample. The results of the study showed that there were statistically significant differences between the means of the values of the test items information function in favor of the four-distractors test form compared to the three-and-five- distractors test form. The results, furthermore, showed that there were statistically significant differences between the means of the values of the test items information function in favor of the five-distractors test form compared to the three-distractors test form.The results, further, showed that there were no differences between the means of the estimate of the items difficulty parameter due to the number of distractors of the item. It was indicated that there were differences between the means of the estimate of the items discrimination parameter concerning the three-and-four-distractors tests in favor of the four-distractors test. It was, besides, shown that there were statistically significant differences between the means of the estimate of the items discrimination parameter concerning the three-distractors and five- distractors tests’ forms in favor of the for the five- distractors test. Keywords: number of distractors, multiple-choice test, item response theory, items’ parameters, information function DOI: 10.7176/JEP/13-13-07 Publication date: May 31 st 2022