The GRE, which made waves in 1993 by transforming into a computer-adaptive exam, is being revamped again:
Although the test will still include sections on verbal reasoning, quantitative reasoning and analytical writing, every section is being revised, and the test lengthened to about four hours, from two and a half hours. About 500,000 students, 20 percent to 25 percent of them foreigners, take the general G.R.E. each year. E.T.S., which administers the test, also offers subject-matter tests in such fields as biology, mathematics and physics, but those tests, taken by far fewer students, are not being changed.To enhance security, every question on the new exams will be used only once, and the test will start at different times in different time zones, so students who have finished cannot pass on questions to those in different zones...
As of next year, the test will no longer be "computer adaptive," with test-takers getting questions tailored to their performance on previous questions, so that each gets challenging questions that provide a clear picture of what they can do. Instead, every student taking the test on a particular day will get the same questions, and those questions will not be reused.
Computer-adaptive tests, as ETS and others have discovered, require item reuse and enormous item pools to prevent any one item from being exposed too often. Good GRE items are not cheap nor easy to come by, and this change addresses security questions and helps to ensure the relationship between the items and the construct by reverting back to the one-use-per-item model. Of course, removing the adaptive algorithm also involves lengthening the exam, because the range in item difficulties for each form once again must be wide enough to adequately assess the geniuses and those who should probably strike graduate school off their "to-do" lists.
Update: Ah, the joys of knowing so many experts. I think this post was up for about two seconds when another psychometrician emailed me to remind me about the CAT version of the ASVAB, the Armed Services Vocational Aptitude Battery. That actually came out before the GRE-CAT, in the late 1980's, and I certainly should have remembered that, considering the truly phenomenal and exhaustive primer that exists on the subject, Computerized Adaptive Testing: From Inquiry to Operation. I can't recommend that book highly enough for anyone who wants to learn more about developing, testing, and implementing a computer-adaptive test.
Posted by kswygert at October 18, 2005 11:05 AM