Arab Educational Information Network

The aim of this study is to identify the psychometric characteristics of the central science test for the third-grade intermediate, which was applied in 2017-2018, it consisted of (40) multiple-choice items. The analyses were according to item response theory. For achieving the objective of the study, (1040) students' answers forms were collected, the results indicated the availability of the assumptions of (IRT) in the test, the three-parameter model was used, it was the most appropriate for the data. The psychometric properties of the test were estimated using R software by the (LTM) package. The results indicated that the most of items were characterized by high level of difficulty, and some items contained a high guessing. In general, the values of the items’ parameters were inconsistency, according to the criteria presented by the measurement literature. Values of the difficulty parameters ranged between (-0.81 to 2.22), values of the discrimination parameters ranged between (0.28 and 3.81), and guessing parameter ranged from (0.00 to 0.50). The test presents the greatest amount of information at above average ability level. There were some recommendations that may improve the quality of the psychometric characteristics of this test, making it an objective and accurate measurement tool in estimating examinees' abilities by using (IRT). (Published abstract)