Letter sent to THES

The Editor
Times Higher Education Supplement

Dear Sir
I would like to draw your attention to an apparent error in the latest world university rankings, which may have rendered them invalid.

The faculty/student score indicates that Duke University was the highest scorer in this category. Therefore, its score was converted to 100 and the other scores adjusted accordingly.It is, in fact, difficult to see how Duke could really be the top scorer in this category. According to the US News and World Report's America's Best Colleges (2007 edition) Duke has eight students per faculty, a ratio that is confirmed by Duke' own data, which refers to a total of 13,088 students, of whom 6,244 were undergraduates, and 1,595 tenure and tenure track faculty, producing a ratio of 8.2. However, the USNWR lists 13 US national universities with better ratios than this, Caltech three to one, Princeton five to one and so on. There are also probably a few non-US institutions that do better.

It is, of course, possible that QS, your consultants, and USNWR adapted different conventions with regard to including or excluding adjunct staff, researchers without teaching responsibilities, medical school staff and so on. This still does not get over the problem. QS appears to have constructed this component of the rankings largely from data entered into files that are available on its web site. These are linked to the 2005 rankings and some no doubt have been revised this year but in general one would expect them to be similar to whatever data was used for 2006.
Thus, QS refers to 2,172 students and 441 staff at Caltech, a ratio of 4.93 students per faculty and 4,633 students and 664 faculty at Rice, a ratio of 6.98. If QS were using these data -- and a quick survey of this category suggests that they were -- then Caltech's ratio of 4.93 and score of 67 would turn Duke's score of 100 into a ratio of 3.3. Rice's ratio of 6.98 and score of 50 would produce a ratio of 3.5 for Duke. In general it appears that QS gave Duke a student to faculty ratio of somewhere between 3 and 3.5.

So Duke, according to QS, would have a ratio of somewhere between 3 and 3.5 students per faculty, which is far lower than any figure that can be derived from the university's current data.
The problem is aggravated by QS's data on Duke which records a total of 12,223 students and 6,244 faculty. The latter figure is obviously far too high and is most probably a data entry error that occurred when someone transferred the figure of 6,244 undergraduates indicated on Duke’s web site to the faculty section in QS's files. This results in a ratio of 1.96 students per faculty, which was probably the figure used by QS in the 2005 rankings. It is probably though not the number used in 2006. If it were, then the scores for other universities would have been very much lower. Rice, for example, would have had a score of around 30 rather than 50 if that had been the case.

It is hard to see how QS came up with the ratio of 3.0 - 3.5 for Duke. It certainly does not come from any information that the university itself has provided. Perhaps it was just another data entry error that nobody noticed.

Anyway, there is no way in which the data can be manipulated, stretched or compressed to put Duke at the top of the faculty- student ratio component. That position probably belongs to Yale, which, according to Yale itself, QS and Wikipedia, has about three students per faculty.Therefore Yale's score, whatever the exact ratio that it represents, should be 100 instead of 93 and the score of everybody except Duke would have to go up accordingly. All the scores for this part need to be corrected and so therefore do the total scores.You might argue that the changes are so small that they are not worth bothering about. At the top, maybe this is true but it might make quite a bit of difference further down. In any case, surely an attempt to rank world-class universities ought to be held to the highest methodological l standards.

If you can provide a reasonable explanation for Duke's high score, such as the use of information withheld by Duke from the general public, I am sure that everybody would be glad to hear it. Otherwise, it might be a good idea to withdrew the rankings and then republish them after they have been thoroughly checked.


Richard Holmes
Shah Alam
Malaysia