Differential Effects of Scopus vs. Web of Science on University Rankings: A Case Study of German Universities

Universities usually shape their research agendas based on internal strategic analyses of their strengths and capacities. Yet, external rankings dominate public perception. This constitutes a tension field, especially because external rankings are not predictable. The change from Web of Science to Scopus in the Times Higher Education World University Ranking (THE) between the 14/15 and 15/16 edition presents a prominent example of unpredictability and, simultaneously, provides an opportunity to investigate these effects with respect to the "Citations" component of the indicator set THE applies. In our case study, we analyse these effects for German Universities. We find that effects are strongly differential for individual universities and, even more, not easily reproducible, which limits predictability and transparency of the ranking. We conclude that University rankings should comply with open data principles and universities should take control of their data to start developing their own indicator systems.