QS World University Rankings 2013

Academic Ranking of World Universities considers every university that has any Nobel Laureates, Fields Medalists, Highly Cited Researchers, or papers published in Nature or Science. In addition, universities with significant amount of papers indexed by Science Citation Index-Expanded (SCIE) and Social Science Citation Index (SSCI) are also included. In total, more than 1000 universities are actually ranked and the best 500 are published on the web.
Universities are ranked by several indicators of academic or research performance, including alumni and staff winning Nobel Prizes and Fields Medals, highly cited researchers, papers published in Nature and Science, papers indexed in major citation indices, and the per capita academic performance of an institution. For each indicator, the highest scoring institution is assigned a score of 100, and other institutions are calculated as a percentage of the top score. The distribution of data for each indicator is examined for any significant distorting effect; standard statistical techniques are used to adjust the indicator if necessary. Scores for each indicator are weighted as shown below to arrive at a final overall score for an institution. The highest scoring institution is assigned a score of 100, and other institutions are calculated as a percentage of the top score. An institution's rank reflects the number of institutions that sit above it.
1- Quality of Education: 10%
2- Quality of Faculty: 40%
3- Research Output: 40%
4- Per Capita Performance: 10%

In this ranking system, top 10 universities belong to USA or Britain. Massachusetts Institute of Technology (MIT) is on the top of the ranking. Harvard University is ranked the second and University of Cambridge is ranked 3rd.
The next ranks respectively belong to: UCL (University College London), Imperial College London and University of Oxford.