Peer Assessment of Contributions to a Group Project: A comparison of holistic and category-based approaches

This paper reports the results of an experiment which compared a holistic and category-based approach to peer assessment of contributions to a group project. Students undertook a group assignment and assessed each other's contributions using the two approaches. Holistic peer assessment yielded a much greater number of groups who awarded each member equal marks than the category-based peer assessment used in the study. The holistic approach also produced a greater proportion of students with a large gain and a large loss of marks than the category-based method. The paper argues that the holistic approach supports the purposes of summative peer assessment methods within group project work better than the category-based approach. However, it is argued that the category-based approach is useful for formative assessment.