www.tjprc.org editor@tjprc.org APPLICATION OF GENERALIZABILITY THEORY IN ESTIMATING SCORE DEPENDABILITY OF ECONOMICS ESSAY TEST FRANCIS ELOCHUKWU IKEH 1 , MERCY IFUNANYA ANI 2 , IJEOMA AWA KALU 2 , ROSELINE IFEOMA IKETEAKU 3 , BEATRICE A. EZE 2 , BARNABAS C. MADU 1 , CATHERINE U. ENE 1 * 1 Department of Science Education, University of Nigeria, Nsukka, Enugu State, Nigeria 2 Department of Educational Foundations, Alex Ekwueme Federal University, Ndufe Alike Ikwo, Ebonyi State, Nigeria 3 Department of Educational Psychology, School of Education, Enugu State College of Education (Technical), Enugu, Enugu State, Nigeria ABSTRACT This study was aimed at estimating the score reliability of Economics essay test using Generalizability Theory, basically to: (a) estimate potential sources of error due to students (persons), items (tasks) and raters (judges) and (b) to obtain reliability estimates of the measurement instrument by increasing the levels of conditions in each facet. Variance due to student by item by rater interaction was the highest contribution of error variance followed by students’ factor. It was also gathered from the analyses of the findings that it would be more efficient to increase the number of items rather than increasing the number of raters in order to maximize the score reliability of Economics essay test. Conclusions drawn from this study were analysis of scores from ratings of students in Economics essay test. KEYWORDS: Generalizability Theory, Essay Test, Score Dependability, Economics Received: Dec 10, 2020; Accepted: Dec 29, 2020; Published: Apr 15, 2021; Paper Id.: IJMPERDJUN202117 INTRODUCTION Essay test is one of the assessment tools used in testing or assessing students’ academic achievement in any given instruction, especially when teachers want the students to originate, organize, express, and integrate ideas in a given problem. Essay test, according to Onunkwo (2002), is a test in which students are required to provide answers to questions and therefore offers students the opportunity to organize and express their ideas in writing. Hence, it is particularly useful in evaluating objectives which deal with selection, arrangement, organization and expression of ideas. In the light of this, essay tests usually provoke critical thinking, originality and ingenuity (Gronlund, 1971). Reiner, Bothell, Sudweeks, and Wood (2002) are of the view that essay tests challenge students to create responses rather than to simply select a response; that is, they usually require a student to compose an answer rather than selecting an answer. Onunkwo (2002) opined that teachers use essay tests because they have the potential to reveal students’ abilities to reason, create, analyze, synthesize, and evaluate. This implies that it will enable the teacher to assess students’ understanding of and ability to think about subject matter content. Reiner et al (2002) opined that essay type requires the students to demonstrate their reasoning and thinking skills, which give teachers the opportunity to detect problems students may have with their reasoning processes. When educators detect problems in students’ thinking, they can help them overcome those problems. These above explanations of essay test indicate that essay tests can be used to: assess higher-order or critical thinking skills, evaluate students’ thinking and reasoning skill; provide authentic experience, test thought process (Reiner et al, 2002), and offer students the opportunity to organize and express their ideas in writing (Onunkwo, 2002). Original Article International Journal of Mechanical and Production Engineering Research and Development (IJMPERD) ISSN (P): 2249–6890; ISSN (E): 2249–8001 Vol. 11, Issue 3, Jun 2021, 221–228 © TJPRC Pvt. Ltd.