World universities are ranked each year by international ranking institutes, which compare the best universities on different parameters.
How rankings are assembled
Each ranking institute adopts its own methodology, assigning different weights to various performance metrics. The metrics that are considered are usually:
- academic perfomance metrics (e.g., number of publications, number of citations, number of Nobel prize winners among the alumni, etc.);
- structural indicators (e.g., teaching staff to student ratio, research funding, number of foreign researchers and students);
- reputational indicators (e.g., opinion survey among academics, students, employers).
Rankings can be either global or by discipline.
LThe available rankings published each year include 800-1200 universities worldwide, quite likely the best ones in an estimated 18000-20000 (3000 of which in the EU area only). The very fact of appearing in those rankings, whatever the position in the rank, amounts to classifying among the top 4%-7% world universities.
| Academic Ranking of World Universities (ARWU) | Quacquarelli-Symonds (QS) World University Rankings | Times Higher Education (THE) | NTU Taiwan |
|---|---|---|---|
| Nobel prizes and Fields medals among alumni (10%) | Academic reputation (40%) | Reputation surveys (32%) | Research production (number of papers) (25%) |
| Nobel prizes and Fields medals among researchers (20%) | Employer reputation (10%) | Teaching performance (12,75%) | Research impact (number of citations) (35%) |
| Highly cited researchers (20%) | Teaching-staff-to-student ratio (20%) | Citations(30%) | Research excellence (e.g., number of highly cited papers) (40%) |
| Papers appeared on Nature or Science (20%) | Citations per faculty (20%) | Financial indicators (16,75%) | |
| Highly cited papers (20%) | International faculty(5%) | International faculty and students (5%) | |
| Other metrics (10%) | International students (5%) | International partnerships (2,5%) |
Why they matter
In the last ten years students mobility has increased considerably around the world. Students who choose to study far from their residence, and especially abroad, choose their university also based on its standing in international rankings. Rankings are also used as a reference by researchers and funding bodies, and they influence their decisions.