Enhancing Accuracy in Peer Assessment by Addressing Bias and Outliers Through Calibration Method

Peer assessment is increasingly used in educational settings as a tool to enhance learning quality and critical thinking. However, this process comes with challenges, such as ensuring the fairness and accuracy of evaluations. In this article, we explore methods for analyzing and correcting student grades within peer assessment systems. Special emphasis is placed on identifying and quantifying biastendencies of individual students to systematically assign higher or lower grades-and on detecting and managing outliers-grades that significantly deviate from the average. We also examine the calibration method, in which students evaluate tests graded by instructors, allowing for the assessment of individual evaluator accuracy. By combining these methods, the accuracy and reliability of peer assessment can be improved, and the results of this research provide guidelines for designing more effective assessment systems.