Study and Strategy questions relating to the GMAT.
Stockmoose16
 
 

MGMAT CAT SCORES...

by Stockmoose16 Tue Oct 14, 2008 3:24 am

Hello,

I've been studying for about 11 weeks now, and I'm trying to get an accurate prediction of where my real gmat score will end up. I've taken 4 MGMAT CAT and the GMATPREP #1. The scores are never very close, despite being taken only a week or two apart.

MGMAT CAT #1 (11 weeks ago): 560
MGMAT CAT #2 (4 weeks ago): 530
GMATPREP #1 (3 weeks ago): 600
MGMAT CAT #3 (2 weeks ago): 640
MGMAT CAT #4 (yesterday): 690

I took CAT #1 untimed. CAT #2 was timed, but I was incredibly rushed for time in the quant section. I was basically guessing the last 10 questions.

CAT #3 and GMAT PREP #1 were timed, and I attribute the improvement to learning a timing strategy where I make an educated guess if I don't have a handle on the problem after 90 seconds.

CAT #4 was taken one week after GMAT PREP #1. I didn't study any new timing strategy. I really didn't learn a whole lot of new material, since the tests were only a week apart.

I've gone froma 530 to a 690 in 3 weeks, and that just doesn't make sense to me. My biggest worry is the verbal scoring, which is highly erratic. On my baseline, I scored in the 91st percentile. On the following 2 CATS, I scored in the 72nd percentile. On the most recent CAT, I scored in the 91st percentile again. Mind you, I haven't devoted any study time to the verbal section, since I scored so strongly on the baseline. Why is there a 19 percentile point difference between exams #2/3 and #1/4?

And finally, on my latest test, the overview said I scored a 42Q (70th percentile) and 40V (91st percentile). My OVERALL percentile rank was 91st percentile. How is this possible? If I scored 70th percentile quant and 91st percentile verbal, even a weighted average wouldn't put me at 91st percentile overall, unless verbal was weighted 100%. According to several charts I've looked at, a 42Q/40V score translates into a 660, not a 690. What is going on here?
StaceyKoprince
ManhattanGMAT Staff
 
Posts: 9361
Joined: Wed Oct 19, 2005 9:05 am
Location: Montreal
 

by StaceyKoprince Wed Oct 15, 2008 12:57 am

CAT1 untimed. So basically we really can't tell much of anything from this. Timing is an enormous factor in the score.

CAT2 timed but ran out of time. Guessed on last 10 - that seriously deflated your score. If you got every one of those 10 questions wrong, the hit to your score was on the order of 15 to 25 percentile points.

GP1 and CAT3 timed and not running out of time so much anymore. Excellent. Love your timing strategy here.

CAT4 timed; didn't do a ton to improve in between tests. Little confused about this, because in your timeline, you said you took GP1 3 weeks ago and CAT4 yesterday. Then you said that you took CAT4 one week after you took GP1. Can you clarify?

These tests do have a standard deviation and that SD is a lot wider than most people guess. The SD on our tests is about 50 points. The SD on the official test is about 30 points (and GMATPrep is about the same). Essentially, these kinds of tests aren't as precise as most people assume they are.

The 530 does make sense - your score was seriously deflated by your timing / guessing issue. I do agree that you should try to figure out what's causing the fluctuation in your verbal scoring. I can't, of course, just know what's causing the difference for you. :) Here are some questions to answer:
How was your timing? Were you able to move steadily through the test and spend the time you're supposed to spend on each question type? Or did you move too quickly or too slowly at times?
Did any mismanagement of time cause you to have to guess randomly or work much more quickly than you would have liked?
How was your performance throughout the section? Did you have any strings of 4+ wrong answers in a row?
How was your performance at the beginning and toward the end? Did you have a much higher incidence of wrong answers in the first 10 or last 10 than you did throughout the rest of the section?
Did you take the test under exact testing conditions? (essays, 10 min break, quant, 10 min break, verbal)
What time of day did you take the test? Did you have something to eat and drink on the breaks? Did you get enough sleep the night before? How did you feel, stamina-wise, during the verbal section?

Finally, on the raw score to scaled score conversion, the calculation is not an average of the two scores (or of the two percentiles). It's a complicated measure of how you compare to the rest of the population across both quant and verbal. They do insert a weighting factor, and verbal does weigh more heavily in that calculation than does math - but, again, this is not an average. You can actually have, in some circumstances, an overal percentile that is higher (or lower) than your two individual percentiles.

GMAC does not publish the specific formula it uses to convert raw scores to scaled scores, so it's a bit of an art to recreate this. Basically, we ask our students to tell us their full data when they take the test. Then our algorithm guy crunches the numbers to map the raw score combinations that lead to specific scaled scores. The raw score to scaled score translation does change a bit over time, so it's important to make sure that you're looking at recent data. I believe our algorithm guy updates our data every 2 months.
Stacey Koprince
Instructor
Director, Content & Curriculum
ManhattanPrep
Guest
 
 

by Guest Wed Oct 15, 2008 3:16 pm

[quote="skoprince"]CAT1 untimed. So basically we really can't tell much of anything from this. Timing is an enormous factor in the score.

CAT2 timed but ran out of time. Guessed on last 10 - that seriously deflated your score. If you got every one of those 10 questions wrong, the hit to your score was on the order of 15 to 25 percentile points.

GP1 and CAT3 timed and not running out of time so much anymore. Excellent. Love your timing strategy here.

CAT4 timed; didn't do a ton to improve in between tests. Little confused about this, because in your timeline, you said you took GP1 3 weeks ago and CAT4 yesterday. Then you said that you took CAT4 one week after you took GP1. Can you clarify?

***Yes, I'll clarify. I took CAT 4 yesterday, three weeks after taking the GMATPREP, which I scored a 600 on.

Here are some questions to answer:
How was your timing?
***Timing was fine for the verbal section. Finished with about 10 seconds to spare. That seems to be the case on every CAT.

Were you able to move steadily through the test and spend the time you're supposed to spend on each question type? Or did you move too quickly or too slowly at times?

***I gave ample time to each question.


Did any mismanagement of time cause you to have to guess randomly or work much more quickly than you would have liked?
*** No.

How was your performance throughout the section? Did you have any strings of 4+ wrong answers in a row?
***On Cat #4 (91st percentile), I never missed 4 in a row. On CAT #1 (91st percentile), I missed 5 in a row early on (Qs 6-10). On Cat #3, I had two strings where I missed four in a row, however, they were mostly 700-800 questions. On CAT #2 (72nd percentile), I had two strings where I missed four in a row, but again, they were 700+ questions.

On almost every CAT, I had at least one string of 5+ in a row correct. If I'm getting 5 correct in a row, then I am able to correctly answer 700 level questions on a regular basis. If that's the case, why am I fluctuating so much?



How was your performance at the beginning and toward the end? Did you have a much higher incidence of wrong answers in the first 10 or last 10 than you did throughout the rest of the section?
***Not really. I don't see a pattern.

Did you take the test under exact testing conditions? (essays, 10 min break, quant, 10 min break, verbal)
What time of day did you take the test? Did you have something to eat and drink on the breaks? Did you get enough sleep the night before? How did you feel, stamina-wise, during the verbal section?

I never take the essays, since they're a waste of time and don't count for much. Therefore, the CATs were all taken under the same time constraints. My stamina was good.

Why am I fluctuating between 72nd and 91st percentile? I just can't figure it out. That is well-beyond a normal standard deviation.
StaceyKoprince
ManhattanGMAT Staff
 
Posts: 9361
Joined: Wed Oct 19, 2005 9:05 am
Location: Montreal
 

by StaceyKoprince Sat Oct 18, 2008 1:25 pm

Do not skip the essays any more. I know nobody cares about the score, but they are NOT a waste of time. Mental stamina is a major issue on this test. If you never practice for the full length of time, your verbal score will almost certainly drop on the real test because you will be more mentally fatigued than you are used to being by the time you get to the verbal.

Your 72nd percentile test was #2 and #4 was 91st percentile. Did you not improve at all in that timeframe? (Obviously your score improved - why do you think that wasn't due to improvement on your part?)

Another question: what were the specific sub-types of questions you got wrong? Go make a list of the categories (eg, RC inference) and also things like: topic of RC passage (eg, science vs. business) or was the CR conclusion obvious or tough to find? When you're done, ask yourself: are there any patterns?

If that doesn't start to give you clues, then try this: go back over your last couple of tests and create an error log. Keep track of:
1) Why did I get it wrong (as specifically as possible)?
2) What could I do to minimize the chance of making that error (or those errors) again?  How will I make whatever that is a habit so that I really do minimize chances of making the same error again?
3) What are the right ways to do it? (for math, there's always more than one way to do a problem)
4) Of the right ways, which one is the best way for me (combining both efficiency and effectiveness) given my strengths and weaknesses?
5) How will I recognize problems of similar type in future so that I can apply that "best way" to the problem?

#1 is how you figure out what's going on here - literally, for every single question, figure out WHY you got it wrong. The remaining questions target what to do about it: look at the collective results and see what patterns emerge. If you're not sure how to interpret, you can come post the data here and we'll help you try to figure it out.
Stacey Koprince
Instructor
Director, Content & Curriculum
ManhattanPrep