Comparative Analysis of Item Parameter Estimates of 2016 Physics WAEC and NECO Senior School Certificate Examination Items Using the 3-Parameter Model of Item Response Theory

Abstract

This study analysed 2016 WAEC and NECO Senior School Certificate Physics Examination Items using Item Response Theory. The study determined the difficulty levels of 2016 WAEC and NECO Physics objective tests. It also investigated the discriminating power of items on WAEC and NECO Physics objective tests and finally ascertained the difference in guessing parameter of WAEC and NECO 2016 physics objective test items. These were done with a view to providing information on the comparability of the psychometrics qualities (discrimination and difficulty) of the examination items. Descriptive survey research design was adopted for the study. The population of the study consisted all public Senior Secondary school Physics student in Osun state. A sample size of 1020, SS3 Physics Students was selected using multi-stage sampling technique. From each of the three Senatorial Districts in Osun State, two Local Government Areas (LGAs) were selected using simple random sampling technique. Three schools were selected from each Local Government Area using simple random sampling technique, making a total of 18 schools. The research instruments for the study were WAEC and NECO Physics objective tests. These instruments were the adopted versions of 2016 WAEC and NECO Physics objective tests. These instruments were administered on the SS3 Physics Students who enrolled for 2019 WAEC. The data were analysed using chi square, mean and standard deviation.
The results showed that the average difficulty levels of NECO and WAEC Physics objective items were 2.11 and 1.25 respectively. Also, the results showed that the average discrimination levels of NECO and WAEC Physics tests items were 3.43 and 2.37 respectively. The results equally showed that the average vulnerability to guessing of 2016 NECO and WAEC Physics test items were 0.13 and 0.16 respectively.
The study concluded that the item parameters of WAEC and NECO Physics objective tests were statistically comparable.