GMAT Prep Test Accuracy

HW · Posted: Thu Apr 26, 2007 11:02 am Post subject: GMAT Prep Test Accuracy

Hello everyone,

My test is this Saturday so I took my final GMAt prep test yesterday and scored a 640, which is ok since all I need is a 600. However, someone told me that the real gmat is much tougher and you can expect a much lower score. Is this true?

isisalaska · Posted: Thu Apr 26, 2007 11:09 am Post subject:

Not necessarily. Tthe GMAT prep is a good indicator of your performance. Godd luck!

manishhemnani · Posted: Thu Apr 26, 2007 1:14 pm Post subject: Re: GMAT Prep Test Accuracy

Stacey Koprince · Posted: Mon Apr 30, 2007 12:27 pm Post subject:

Just be aware that the official GMAT has a standard deviation of 29 points. GMAC has not released the figure for the GMATPrep software, but the software should have a higher standard deviation b/c it is only a subset of the real thing (and, therefore, not as statistically valid).

What does it mean to have a st.dev. of 29? Take your 640. If that had been the real test, you could expect a 2/3 chance of scoring between a 610 and a 670 if you took it again, and you could expect a 1/3 chance of scoring below a 610 or above a 680 if you took it again.

In other words, the standard deviation is pretty large - and that's on the real thing. The standard deviation on any test that just mimics the real thing is going to be even larger.