I know that it is impossible to say how many correct answers I should have in the real test to get a 41-43 in Verbal. The algorithm doesn't work in that way.
However, in my GMAT Prep experience I noticed that even, if I get 12-13, questions wrong I can get a 49 in the quant score as long as I have answered some difficult questions.
In this sense, I would like to know that whether the verbal section works in the same way. Is it possible to get a 42 with 11-13 wrong answers? According to my experience, it seems that we have to answer correctly more questions.
This is a response to your pm. My friend, I wish I had the information available to give you an intelligent and fully informed opinion. To some extent, what you are asking dives into the mystery of the CAT. GMAC operates a proprietary algorithm designed by some truly incredible data-heads, and all of us in GMAT prep are on the outside looking in. Yes, I would love
to get the inside scoop on how that algorithm worked, but even if, by hook or crook, I somehow got a hold of that proprietary information, if I started to broadcast it, they would throw my butt in the slammer and throw away the key! So, you see, I don't have quite the same authority answering this question that I would have, say, answering a math or grammar question.
First of all, I know for a fact that the CAT algorithms for Quant and Verbal are at least slightly different. I know this because GMAC released an analysis of their own data, with regard to guessing strategies, which I discuss here:http://magoosh.com/gmat/2012/guessing-s ... -the-gmat/
I don't know much about the details of this difference, but it wouldn't surprise me at all that similar performances, in terms of number of right/wrong, would produce somewhat different raw scores in Q vs. V.
Also, I would encourage you to think past the very crude measure of number
of correct answers. That's how high school tests work, but that's not how the CAT works. Theoretically, two different people could have similar numbers of questions right and wrong but get radically different scores. With the CAT, what matters is the difficulty of each question --- if you get difficult questions right, then that will mean something quite different from getting easy or medium questions right. The algorithm is sophisticated enough that those of us who don't have a Ph.D. in Statistics probably wouldn't understand it even if they showed us all the details --- which, of course, they are not going to do.
I know this isn't a full answer to your question, but I hope it helps.
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