This project employs bibliometric methods to analyze and rank the scientific papers performances of the top 500 universities in the world. The selection of the 500 universities for inclusion in this project is primarily based on information obtained from the Essential Science Indicators (ESI). Of the more than 3,000 research institutions listed in ESI, this project selects the top 700 institutions sorted by the numbers of published journal articles. Exclusion of non-university institutions from the primary list and the comparison to the lists of universities included in the other ranking programs resulted in the 678 universities in this project. Data used to assess the performances of the universities is drawn from ISI’s ESI, Web of Science (WOS), which includes SCI and SSCI, and Journal Citation Reports (JCR).

    The concept of authority control is employed to retrieve data indexed under different forms of a university’s name in those resources – i.e., the official name, the abbreviated and other possible forms of the names. This project also considers the mergers and splitting of universities (or different campuses in a university system) and includes publications by a university’s affiliated institutions such as research centers and university hospitals. This effort ensures the accuracy of each university’s number of published journal articles and the subsequent statistics of their citations.

  The performance measures are composed of nine indicators representing three different criteria of scientific papers performance: research productivity, research impact, and research excellence. Table 1 lists the indicators and shows their respective weightings for the indicators.

Research Productivity:

  The number of articles published in peer-reviewed academic journals is an appropriate indicator of the productivity of a research institution. To fairly represent a university’s on-going and current research productivity, this project employs two indicators: the number of articles in the last eleven years (1996-2006), and the number of articles in the current year (2006).

  Number of articles in the last 11 years” draws data from ESI, which include 1996-2006 statistics of articles published in journals indexed by SCI and SSCI. “Number of articles in the current year” relies on the 2006 data obtained from SCI and SSCI, which were searched between July 2 and July 20, 2007.

Research Impact:

  The number of citations on a particular academic article within a specific time frame is a commonly accepted indicator for that article’s impact. This project considers both the long-term and short-term impacts of a particular research and seeks to provide a fair representation of a university’s research impact regardless of its size and faculty number. Thus, this project measures research impact by: the number of citations in the last eleven years, the number of citations in the last two years, and the average number of citations in the last eleven years.

  ‘Number of citations in the last 11 years” draws 1996-2006 citation statistics from ESI. “Number of citations in the last 2 years” draws 2005-2006 citation statistics from SCI and SSCI at WOS, which include citation statistics updated to the dates of retrieval. “Average number of citations in the last 11 years” is the number of articles in the last eleven years divided by the number of citations in the last eleven years.

Research Excellence:

  This project assesses each university’s research excellence by the following indicators: the h-index of the last two years, the number of Highly Cited Papers from ESI, the number of articles in high-impact journals in the current year(Hi-Impact journal articles), and the number of subject fields where the university demonstrates excellence(fields of excellence). “H-index of the last 2 years” measures both the quantity and quality of a university’s research via the use of the 2005-2006 data from SCI and SSCI. It is defined as “a university has index h if h of its Np papers in the last two years have at least h citations each and the other (Np – h) papers have ≦h citations each”.

  “Number of Highly Cited Papers” utilizes data from ESI, which include statistics of “Highly Cited Papers” from 1997 to February, 2007. ESI defines Highly Cited Papers as SCI /SSCI-indexed papers that are cited most (in the top 1% of the total papers indexed in the same year) within the last ten years.

  “Number of articles in high-impact journals in the current year” employs data from JCR, which supplied the impact factor of each journal in its subject field. This project defines high-impact journals as journals whose impact factors ranked as the top 5% of the total journals within a specific subject category. With high-impact journals lists derived from JCR, this project is able to count the numbers of each university’s articles published in high-impact journals by subject.

  “Number of subject fields where the university demonstrates excellence” employs data from ESI which categorized the indexed journals into twenty-two subject fields. For each subject field, ESI’s Citation Rankings include a list of institutions whose publications (SCI/SSCI indexed articles) receive the most citations. An institution’s inclusion in a specific field’s list suggests its excellence in that particular field because the list includes only the most frequently cited institutions (within the top 1% of the total institutions). Based on the data, this project is able to identify the number of subject fields where each university demonstrated excellence. This indicator ensures that smaller universities concentrating on a few high-impact subject fields have a better representation in the measurement of research quality.

    The procedures for data processing are as follow. First, the project staff conducts authority control on the various forms of a university name and analyzes all the SCI/SSCI bibliographic records in which the address field contained one of the forms of the university name. An accurate number of the total articles from a university is obtained after removing duplicate records containing different forms of that university’s name. Second, using SCI/SSCI, this project obtains the total number of citations by adding the number of citations on each of the articles from that university from its inclusion in SCI/SSCI to the date of retrieval for this research.

  Some university systems have several campuses. A few campuses within a particular university system may have been commonly perceived as individual institutions. However, they are indexed in ESI only by the university system name. For example, University of Wisconsin-Madison and University of Wisconsin-Milwaukee are not differentiated in ESI (they are both indexed under “Univ Wisconsin”) though they are often perceived as two individual universities. This project corrects the flaw by manually searching SCI/SSCI in order to identify the actual number of articles and citations of these articles produced by each individual campus. Likewise, this project employs the same manual searching procedures to ensure the measurement of each university’s Highly Cited Papers have fairly represented the research performance of each individual university campus.

  Based on the measurement procedures, this project calculates a university’s score for each of the nine indicators. For each indicator, the university with the highest number receives the maximum points (100); the other universities’ numbers are subdivided by the highest number and are converted decimally into their respective scores. For example, if University A has the highest number M for Indicator X, it receives 100 for that indicator, while University B with a number of N receives (N/M×100) for that particular indicator. Finally, the project calculates the final score of each university by the indicator weightings presented in Table 1 and sorts the universities by their final scores. Universities with the same scores are sorted alphabetically. It should be noted that many universities obtain similar scores, and the slight differences of the final scores must be interpreted carefully. A university’s slightly higher score than another university’s may not necessarily suggest its superiority in scientific research because the two universities might be in very close proximity in the ranking.