Embracing openness and AI: CWTS Leiden Ranking Open Edition

Presentation given at the 16th University Ranking Forum of Korea (URFK2025): AI and University Rankings on November 20, 2025. How can openness and AI reshape the way we understand universities worldwide? In this talk, Nees Jan van Eck, senior researcher and head of data science at CWTS, Leiden University, will share how principles of responsible research assessment have guided the evolution of the CWTS Leiden Ranking. Building on two decades of experience in university-level bibliometric analytics, CWTS launched the Leiden Ranking Open Edition in 2024, offering a fully transparent alternative based on open data from OpenAlex. The 2025 release of the Leiden Ranking Open Edition takes this further by including so-called non-core publications and expanding coverage to more than 2,800 universities worldwide. By combining open data with cutting-edge methods — including an open, AI-assisted approach for classifying publications — the Leiden Ranking Open Edition offers a more transparent, inclusive, and richer view of academic performance across the globe.