Assessing Score Dependability of West Africa Examination Council (WAEC) 2019 Mathematics Objective Test Using Generalisability Theory

This study investigated score dependability in the 2019 West Africa Examination Council (WAEC) Senior Secondary School examination using the generalisability theory. The study was specifically concerned with identifying and analysing the score dependability of the Senior Secondary School 2019 WAEC mathematics objective examination using generalisability theory, and determining the highest contribution of facets: students, items and teachers to score dependability. Two research questions were raised to guide the study. The study was a survey which adopted a random effect two-facet fully crossed s×r×i design for generalisability (G) and decision (D) studies. The population consisted of fifty-six thousand, seven hundred and ninety-seven (5697) Senior Secondary three (SS3) students in the seventy-five (75) public secondary schools in Benin Metropolis for the 2019/2020 academic session. The instrument for data collection was a fifty (50) multiple choice WAEC, Mathematics 2019 examination. The instrument had been validated by the West African Examination Council (WAEC). The reliability of the items was ascertained using the Kuder – Richardson 20 (KR 20) to obtain internal consistency. It gave a value of 0.92. Data collected were analysed using the software EduG version 6.0-e based on analysis of variance (ANOVA) and generalisability. The findings which emerged from the study were the highest effects to score dependability in examination came from the interaction of students and teachers, an index of dependability (∅)of 0.92 high enough to maximise reliability was observed only when the teachers were increased to 78. Based on the findings, it was recommended that generalisability analysis should be carried out by researchers, test developers and examination bodies so as to reduce or eliminate measurement error and hence maximise reliability, and there should be enough invigilators when conducting examinations, thereby minimising error and maximising reliability (dependability) of examination scores.