GMAT Strategy

Heppy New Year everyone!

I sincerely hope that you had a wonderful celebration and/or a nice break and hope that you are as eager as I am to launch into 2007 with loads of energy and aspiration.

As you know, Stacey Koprince, one of ManhattanGMAT's expert instructors and Director of Corporate Development, has joined me in representing ManhattanGMAT here at Beat The GMAT! While you should definitely direct the content questions to her, please feel free to send me notes about your timing, study plans, program choices, etc. I will also continue to post articles from our archive of strategies as well - in fact - here's the first installment for January 2007:

Inside the Mind of a GMAT Test Writer
A four-part GMATTERS series

PART ONE:
If you have spent any time preparing for the GMAT, you already know that it is a Computer Adaptive Test ("CAT"). CATs operate by basing the difficulty level of each subsequent question on the difficulty level of the previous question and whether you got it right or wrong. So, for example, if you answer a question correctly, your next question will be even harder. If you answer it incorrectly, your next question will be somewhat easier. But how do the test writers at GMAC (the Graduate Management Admissions Council) determine which questions are harder than others?

First, a process called "normalization" takes place, wherein all freshly written questions are tested by actual test takers to determine what percentage answer the questions correctly. If too many people answer correctly, the question may need to be toughened up. If too few people answer correctly, the question may need to be dumbed down. The GMAC test-writers are looking to assemble a pool of questions that covers a range of difficulty, from cakewalk to mind-bending. And the test takers help them do so.

How does GMAC find these test takers? Easy. Everyone who takes the GMAT will end up answering approximately 10 unscored "experimental" math questions and 10 unscored "experimental" verbal questions. These questions are interspersed with the actual, scored questions with no way to identify them as experimental. So you, the test taker, do the dirty work.

Second, the writers at GMAC have a general sense of what makes a "500-level" question, a 600-level, 700-level, etc. (By the way, when we talk about a "500-level" question, for example, we mean that if that question represents the hardest level you reach on the exam, you will score in the 500 range.) Since each test is designed to evaluate proficiency in the same range of topics, the writers have to come up with ways to test the same concepts at different levels of difficulty. For example, let's say the writers want to test your understanding of percentages. Consider the following progression:

What is 12.5% of 48?

If 6 is x% of 48, what is the value of x?

If x/48 = 6.25/50 , what is the value of x?

There are 3 marbles in one bag, 2 blue and 1 red. There are 16 marbles in another bag, 1 yellow, 3 blue, 5 green, and 7 red. If one marble is selected from each bag at random, what is the probability that both marbles are blue?

There are 48 men in a certain rowing club. 5/12 of the men are handsome but not rich. 11/24 of the men are rich. What percentage of the men are neither rich nor handsome?

Notice that the answer to all these questions is basically the same, but the amount of thought needed to solve them varies considerably. All the test-writer does is add layers of information to the question to hide the core concept being tested. As you progress in difficulty, the test is less interested in whether you can perform basic calculations and more interested in whether you can peel away the layers to get to the core.

As you prepare for the GMAT, you need to keep this in mind. Every difficult question is, at heart, a puffed-up version of a simpler question. Practice dissecting math questions to see what the underlying concept is, then retrace your steps and see how GMAC layered the information to make the question more difficult. If you can master this skill, or become even moderately proficient, your performance should improve accordingly.

Have a great week, and I'll post the second installment around the 18th!
Kim