Estimation of Item Parameter Indices of NECO Mathematics Multiple Choice Test Items Among Nigerian Students

The study estimated the difficulty, discrimination, and vulnerability to guessing 2016 National Examination Council (NECO) Mathematics multiple-choice test items. employed an ex-post facto design with 276,338 samples. research instruments used for were Optical Marks Record Sheets NECO June/July objectives responses of testees scored dichotomously. Data collected calibrated using four parameters logistic model. results showed that most items in good as their difficulty within (-2 2). For those items, parameter estimates are considered good. Also, indicated only 21.7% had a very discriminating power, majority poor discrimination power. result implies not effective between examinees required ability lack ability. Finally, revealed vulnerable (i.e., 86.7% terms guessing). concluded indices.