Subject Ranking 2013-14: Physical Sciences methodology

The Times Higher Education World University Rankings’ Physical Sciences subject ranking includes a wide range of narrower subject areas, defined by our data partners Thomson Reuters.

The full list of Physical Sciences subjects used to create this ranking is:

• Astronomy & Astrophysics
• Chemistry
• Crystallography
• Earth Sciences
• Mathematics & Statistics
• Meteorology & Atmospheric Sciences
• Nanotechnology
• Physics
• Polymer Science
• Physical Sciences - Other topics

Different weights and measures

The subject tables employ the same range of 13 performance indicators used in the overall World University Rankings, brought together with scores provided under five categories.

However, the overall methodology is carefully recalibrated for each subject, with the weightings changed to suit the individual fields.

The weightings for the Physical Sciences ranking are:

Teaching: the learning environment – 27.5 per cent
Research: volume, income and reputation – 27.5 per cent
Citations: research influence – 35 per cent
International outlook: staff, students and research - 7.5 per cent
Industry income: innovation – 2.5 per cent

Criteria
No institution can be included in the overall World University Rankings unless it has published a minimum of 200 research papers a year over the five years we examine.

But for the six subject tables, the threshold drops to 100 papers a year for subjects that generate a high volume of publications and 50 a year in subjects such as social sciences where the volume tends to be lower. Although we apply some editorial discretion, we generally expect an institution to have at least 10 per cent of its staff working in the relevant discipline in order to include it in the subject table.

The majority of institutions in Thomson Reuters’ Global Institutional Profiles database provide detailed subject-level information.

In rare cases where such data are not supplied, institutions are either excluded or public sources are used to underpin estimates.