Natural Selections recently reported on scientific productivity (“Under the Covers,” May 2005) at The Rockefeller University (RU). Here we examine the place of RU in the world and the status of its graduate program. Three sources were consulted: (1) The Academic Ranking of World Universities 2005, a study undertaken annually by the Shanghai Jiao Tong University Institute of Higher Education (ed.sjtu.edu.cn), (2) ScienceWatch, a monthly editorial component of Essential Science Indicators, itself a subsidiary of Thompson Scientific best known to us for its ISI Web of Knowledge (www.sciencewatch.com), and (3) America’s Best Graduate Schools 2006 Premium Online Edition, a commercial product from US News and World Report (www.usnews.com).

As the Shanghai Jiao Tong University Institute of Higher Education points out, the quality of universities cannot be precisely measured by mere numbers. Thus, any ranking is controversial and no ranking can be absolutely objective. There are many methodological problems including the proportion of indicators for teaching and services, the weight of per capita performance, the type of institution, the language bias in publication, the selection of awards, and the experience of award winners. Technical problems include the definition of institutions, the attribution of publications and awards, and the history of institutions.

With these caveats in mind, we turn to their study. It ranks universities by several weighted indicators of academic and research performance on a global, regional, and national basis. Indicators include (a) quality of education—the number of alumni receiving a Nobel Prize or Fields Medal weighted by decade (weight: 10%), (b) quality of faculty—the number of staff with a Nobel Prize or Fields Medal awarded while working at the institution (weight: 10%), highly cited researchers (weight: 20%), (c) research output—the number of articles published in Nature and Science between 2000 and 2004 weighted by author position (weight: 20%) and the number of articles in the Science-Citation Index (weight: 20%), (d) academic performance with respect to the size of the institution—given as the weighted scores of the indicators divided by the number of full-time equivalent academic staff (weight 10%). They report that in their study of more than 2,000 universities, RU achieves a global ranking of 30th, a regional ranking (North & Latin America) of 23rd, and a country ranking of 22nd.

ScienceWatch provides a variety of more detailed analyses based on citation data. In a recent five-year ranking of total citations for papers published and cited between 1999 and late 2003, RU did not appear in any of the ‘Top Ten’ rankings of the top 100 federally funded US universities for Biology & Biochemistry, Molecular Biology & Genetics, Immunology, Microbiology, or Neurosciences. However, the measure of total citations favors larger institutions that produce a high volume of papers. Ranking by impact (citations per paper) allows smaller universities to compete more equitably. ScienceWatch also compares impact figures to a world baseline representing the impact of the field during the same period (‘relative impact’). For papers published and cited between 1997 and 2001, the result for RU was dramatically different when rankings were based on these measures. RU was the top ranked institution for Biology & Biochemistry and Immunology with relative impact factors of 150% and 241%, respectively. The next closest institutions rated 116% (U Texas Southwestern) and 105% (Yale), respectively. RU was ranked 2nd for Neurosciences with a relative impact factor of 111%, cf. Caltech (124%), and ranked 3rd for Molecular Biology & Genetics with a relative impact factor of 136%, cf. MIT (179%), and U Texas Southwestern Medical Center at Dallas (147%).

How does RU’s performance in Molecular Biology & Genetics rank globally? In a ScienceWatch study of 37 institutions that garnered more than 50,000 citations in the decade from 1992 to August 2002, RU was ranked 19th overall with 1,232 papers averaging 56.06 citations per paper (7th highest citation rate), of these 3.73% were ranked as highly cited (in the top 1%).

US News points out there are not many rankings of graduate schools, although there is a National Research Council study that reports every 10 years (last published in 1995). The US News ranking of the sciences is released every three to four years with the last for biological sciences published in January 2002. It is based on a peer assessment survey of deans, program directors and department chairs, or faculty members that was collected from U.S. institutions in the fall of 2001. They were asked to rate the quality of the programs in their field on a 1-5 scale with the option of “I don’t know.” With a response rate of 31% in the biological sciences, RU was ranked 8th. By field, RU was ranked 7th in Cell Biology, 10th in Biochemistry, 13th in Molecular Biology, and was unranked out of 9 institutions in Microbiology.