Evaluating reliability of final exam questions via rasch model

Abstract

Students grade in a subject is determine mainly from the final examination marks. The final exam questions need to be reliable in order to measure the performance of students in the particular subject. Rasch model able to measure the reliability of an instrument, the final exam questions. A total of 114 students from Mechanical Engineering department sat for the Engineering Statistics subject. Marks were entered in excel and transferred as *prn format. Marks were analyzed against Rasch model, WINSTEPS. The summary statistics for person, summary statistics for item, item statistics, item dimensionality and item correlation are among the output being analyzed. One item is identified as misfit item. The Engineering Sattistics exam questios was very reliable and able to give insight view of the questions. A corrective action is taken to review the misfit item and rephrase the item.