Tomilola, A. R.Owolabi, H. O.Daramola, D. S.2024-04-242024-04-242016-0713. Tomilola, A. R., Owolabi, H. O. & Daramola, D. S. (2016). Equating of the senior secondary school WASSCE Economics Multiple-Choice papers (2011 and 2015). Journal of Educational Research and Development (AJERD).3, 167-175. Published by Association of Educational Researchers and Evaluators of Nigeria.2536-6899https://uilspace.unilorin.edu.ng/handle/123456789/12743The non-stability of the percentages of failure and passes each year has necessitated the comparability of test scores from different test forms. Since the test scores as the major yardstick through which student achievement is determined. It is important that test scores be comparable from one test form and year to another. This study equated the Senior Secondary School WASSCE Economics Multiple-choice papers (2011 and 2015) as well as investigated (i) ability levels; (ii) difficulty level of 2011 and 2015 WASSCE Economics multiple-choice items (iii) result of the linking item and (iv) horizontal equating of 2011 and 2015 WASSCE Economics multiple-choice items. The Non-Equivalent Anchor Design of test score equating was used and the sample consisted of 650 senior secondary three students selected from 14 secondary schools in Kwara Central Senatorial District. The 2011 and 2015 multiple-choice Economics papers were adopted and used as instruments in this study. The data were analysed usingWINGEN and IRTEQ IRT software packages. The examinees who took 2011 and 2015 WASSCE Economics test items with mean ability of 3.16 and 2.93 respectively had the same ability (ii) 2011 and 2015 WASSCE items were found to be of moderate difficulty at 0.083 and 0.098 respectively (iii) the mean difficult of linking items was moderate at 0.41% difficulty coefficient and (v) it was revealed that a score of 4 in 2011 was found to be equivalent to a score of 2.33 for the MS in 2015, a score of 10 in 2011 is equivalent to a score of 7.54 for the MS in 2015, also a score of 23 in 2011 is equivalent to a score of 22.63 for the MS in 2015. Thus, IRT equating method should be employed in equating test scores since it is an improvement of the Classical Test Theory and also developed to overcome the limitations of classical test theory (CTT) traditional method of equating.enArticle