Kennedy, Ian G.Vossen, Paul H.Igel, ChristophUllrich, CarstenWessner Martin2017-10-052017-10-052017978-3-88579-667-1https://dl.gi.de/handle/20.500.12116/4858Teamwork is commonly required in the industry [Sa95]. At university, students learn teamwork by working in groups, for example during a software development assignment. Teamwork affects their productivity. Lecturers evaluate their overall group performance. Lecturers also need to assess the cooperation of each team member. Cooperation data comes from the students involved, e.g., via a questionnaire. Here we draw attention to specific items for assessment. We then show how to merge or aggregate evaluations using the lecturer's overall quality scale and the students’ peer assessment scale. To this end, we will explain and demonstrate the underlying Split-Join Invariance principle using two compatible scoring formulae.enGradingPeer AssessmentPerformance RatingQuality ScaleScoring RuleScoring RubricSplit-Join Invariance (SJI)Team Cooperation1617-5468