Like the overall performance ranking, the field-based ranking utilizes bibliometric data of 1997-2007 from ESI, WOS, and JCR. The HEEACT ranking employs ISI’s subject categorization of the journals and ranks the world universities accordingly.

The primary pool of world universities contains 700 universities. The ranking then checks the top 300 universities each based on four criteria; “the number of articles in the last eleven years”, “the number of citations in the last eleven years”, “the number of articles in the current year” and “the number of citations in the last two years” to see if miss the excellent schools in each field. And the result is keeping 700 samples of each field except ENG field adding 2 more schools (702). For each field the ranking lists the top 300 universities in the final report.

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 indicators employed in the field-based ranking and their respective weightings in the composite measures are identical to those used in the overall performance ranking. Table 2 shows the criteria, indicators, and their respective weightings used by field-based ranking.

Table 2: The Criteria, Indicators, and Their Respective Weightings Used by Field-based Ranking

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 (1997-2007), and the number of articles in the current year (2007).

“Number of articles in the last 11 years” draws data from ESI, which include 1997-2007 statistics of articles published in journals indexed by SCI and SSCI. “Number of articles in the current year” relies on the 2007 data obtained from SCI and SSCI, which were searched between Jan 19 and Jan 31, 2008.

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 for each of the six fields 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 1997-2007 citation statistics in each field from ESI. “Number of citations in the last 2 years” draws 2006-2007 citation statistics in each field 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 in each of the six fields by the following indicators: the h-index of the last two years, the number of Highly Cited Papers from ESI, and the number of articles in high-impact journals in the current year (hi-impact journal articles). “H-index of the last 2 years” measures both the quantity and quality of a university’s research in each field via the use of the 2006-2007 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 2007. ESI defines Highly Cited Papers as SCI /SSCI-indexed papers that are cited most (in the top 1% of the total papers for each of the six fields 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 supply 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 field. 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 each field.

The procedures for data processing are as follow. First, the project staff conducts authority control on the various forms of a university’s name and analyzes all the SCI/SSCI bibliographic records in which the address field contained one of the forms of the university’s name. An accurate number of the total articles in each of the six fields 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 in each field by adding the number of citations on each of the articles in each field 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 in each of the six fields. 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 by fields.

Based on the measurement procedures, this project calculates a university’s score for each of the eight indicators in each of the six fields. 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 2 and sorts the universities by their final scores for each of the six fields. 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.

The HEEACT ranking categorizes all subject disciplines into six fields and ranks each university’s performance by fields. Table 3 shows the six fields of the HEEACT field-based ranking. The detailed subject categories of each field are listed in the Appendix.

Table 3: Six Fields of the HEEACT Field-based Ranking

Appendix Subject Categories by Field