Archive for November, 2004

How do GMAT scoring algorithms affect you?

Friday, November 19th, 2004

Want to learn more about GMAT scoring algorithms and how they affect you on test day?

One of the important benefits of a GMAT preparation plan that includes simulated GMAT exam sessions with the CATPrep GMAT Simulator is the feedback offered by the incredibly accurate scoring engine included in the simulator software. Students and instructors worldwide depend on our simulator to determine when a prospective test taker is prepared to achieve his or her desired score on the GMAT exam. Testimonials like that of a recent customer who earned an identical score with our software and on the actual exam are one way that we monitor the performance of our software, but many users have expressed interest in the finer points of how we successfully emulate GMAT scoring. In the next few paragraphs, I will attempt to shed some light on this subject.

The actual calculations for raw, scaled sectional, and cumulative scores are not published by Educational Testing Service (ETS), the current publisher of the actual GMAT exam, and the goal of the GMAT is to produce scores that are consistent year to year. In other words, a 650 from several years ago is supposed to be equivalent to a 650 today. To meet that goal, the scaled sectional scores continually fluctuate with regard to the associated percentile. For example, average quantitative scores have been rising for several years and it now takes a scaled score of 51 to reach the 99th percentile while a 48 now represents only the 87th percentile. By comparison, in the verbal section, there is a 7 point difference between the 99th (a score of around 45) and the 87th percentile (around 38).

Since these types of scoring adjustments are not announced publicly, the only reliable way to monitor these scoring fluctuations is to use observations of actual test scores. So clearly software algorithms must be continually monitored and adjusted to provide accurate scoring assessment. At CATPrep we devote the large majority of our effort towards the reliable reproduction of the total cumulative score with regard to test taker performance. We continually adjust our formula for cumulative score generation along with question pool content to reflect the observations and feedback of actual test takers. In stark contrast, many inferior GMAT preparation software products use static formulas and question pools that bear no resemblance to the current exam.

It is important to note that there is no simple relationship between the number of questions answered correctly during a single GMAT session and the associated cumulative score. Each question in each section of the GMAT is assigned a unique weight and earlier questions in the section are worth more than later questions while quantitative questions are generally worth more than verbal ones. Students should be aware that the cumulative score on the GMAT is calculated in increments of 10 points. So, the difference between a 690 and a 700 is only one “tick”. This difference may be attributable to a difference in the number of correct responses, but that is not necessarily the case. 10 points is so narrow a margin in the cumulative GMAT score that the order of your incorrect responses could be the determining factor in whether you receive a 690 or 700.

For example, if you miss 3 verbal questions towards the end of the section during one GMAT session, but miss the same 3 questions in the middle during another session, your second session could easily be scored 10 points lower. This is one reason why our recommended GMAT instructors suggest that you give more attention to the earlier questions on each section. Quite simply, the earlier questions are worth more.

I hope this information helps resolve some of your questions pertaining to the mysterious GMAT scoring algorithms. If you have any further questions or concerns, please do not hesitate to contact us. If you haven’t already, we suggest you read our instructions on how to “Verify Your Preparation Level” using our simulator. The instructions are available on our main GMAT page.

-Cindy Anderson