Statistical significance and effect sizes of differences among research universities at the level of nations and worldwide based on the leiden rankings

The Leiden Rankings can be used for grouping research universities by considering universities which are not statistically significantly different as homogeneous sets. The groups and intergroup relations can be analyzed and visualized using tools from network analysis. Using the so‐called “excellence indicator” PP top‐10% —the proportion of the top‐10% most‐highly‐cited papers assigned to a university—we pursue a classification using (a)...