The GMAT Algorithm and initial estimate

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by zuleron » Sun May 17, 2009 6:49 am
skang357 wrote:I'd rather skip a few hard questions in the middle and then try to answer all of them at the end with ample time than try to get the first 10 right or the first 5.
But don't skip too many in a row coz that WILL tank your score.

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by skang357 » Sun May 17, 2009 9:27 am
zuleron wrote:
skang357 wrote:I'd rather skip a few hard questions in the middle and then try to answer all of them at the end with ample time than try to get the first 10 right or the first 5.
But don't skip too many in a row coz that WILL tank your score.
Yeah thanks... you don't want to skip two in a row. Skipping is only an option that prevents you from getting vested in one question for more than 3 minutes. Even three minutes is too long really but if you solve a few questions in 3 minutes you are bound to get a few that takes you less than a minute to even things out.

Also, I think it's better to "skip" or guess the last 7/8 questions versus the ones in the middle.

I think the greatest bulk of your score is determined by Questions 1-10 and then 20-30. More or less the beginning and the middle.

Skipping means guessing because it's pretty much known that guessing always beats literally skipping a question and getting it wrong. Because it's an adaptive test, if you "skip" it (guess it) and get it wrong, the next question should be easier and that should take care of the problem of getting two questions in a row wrong because hopefully you 'd be able to solve the next one. If the next one is hard/harder maybe you guessed the previous one right. This should at least solve the problem of getting multiple questions wrong in a row more or less.
Impossible is nothing

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by zuleron » Sun May 17, 2009 12:32 pm
skang357 wrote:
Also, I think it's better to "skip" or guess the last 7/8 questions versus the ones in the middle.

I think the greatest bulk of your score is determined by Questions 1-10 and then 20-30. More or less the beginning and the middle.
This is definitely not true. If you get the last 7 wrong your score will suffer badly especially if you were scoring high. i.e. if you were scoring 750 at Q 30 and you get the rest wrong, my guess is you'll probably end up with a 600 or sth. Be very careful with this approach and read the post by Stacey Koprince above.

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by zuleron » Sun May 17, 2009 12:43 pm
skang357 wrote:
Because it's an adaptive test, if you "skip" it (guess it) and get it wrong, the next question should be easier and that should take care of the problem of getting two questions in a row wrong because hopefully you 'd be able to solve the next one. If the next one is hard/harder maybe you guessed the previous one right. This should at least solve the problem of getting multiple questions wrong in a row more or less.
I think you should only skip if you absolutely have to. If you skip one than the get the next one right and then skip the next and get the following one right etc. it is hard to see how your score could increase... and the aim is to get as high a score as possible. Be careful.

I think the best way to approach it is to try answer every question with your best effort and only guess beucause you have to -- not with the aim of getting an easier question. Whenever I guess, it is with a little disappointment coz I know I am going to get an easier question which means I reduce my chances of getting a higher score. I only do it because I know that not guessing will cost me more points later on. Remember, the aim is to get harder and harder questions in order to elevate your score, rather than to get easier question in order to avoid consecutive errors. In other words, guessing is a measure of last resort not an affirmative strategy.

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by skang357 » Sun May 17, 2009 1:52 pm
zuleron wrote:
skang357 wrote:
Also, I think it's better to "skip" or guess the last 7/8 questions versus the ones in the middle.

I think the greatest bulk of your score is determined by Questions 1-10 and then 20-30. More or less the beginning and the middle.
This is definitely not true. If you get the last 7 wrong your score will suffer badly especially if you were scoring high. i.e. if you were scoring 750 at Q 30 and you get the rest wrong, my guess is you'll probably end up with a 600 or sth. Be very careful with this approach and read the post by Stacey Koprince above.
I think what you're saying holds true if you're doing really awesome and then you bomb the last 7 questions. But if you're scoring somewhere lower than that, the last 7 do not hurt you as much.

It seems like the last 7 questions are in the 500 to 600 range. Maybe even the 300 to 500. The last 7 do not seem to contain the 700 to 800.

I guess it all depends on what kind of level you are as a test taker....

Yeah I think skipping questions is something only to do to justify getting a higher score. Dunno but I say it's better to get 3 600 to 700 questions right then get 1 700 to 800 question right then only have time to solve one of the of 3 600 to 700 questions.

Jeez there are so many different variations and trees you can go down. This why I say just forget about everything and stick to answering everything within 2 minutes and 3 minutes if it's a 700 to 800 level question.
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by 4seasoncentre » Sun May 17, 2009 7:11 pm
My advice on guessing is that you hopefully guess at the start of a question before you invest too much time.

When you read a question you need to decide:

A) I can probably get the right answer fairly quickly
B) This looks tough, but if I invest up to about 4 mins I honestly think I can get the right answer
C) Screw this! I'm not wasting any time- C looks kinda right.

The worst situation would be for you to invest several minutes on a question, and not be any closer at the solution. In this case you get it wrong, and you lose time.

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by doclkk » Thu May 21, 2009 12:08 pm
I've read and heard so many things about scoring. Most of it agrees but I guess I will just lay out what I'm confused about.

1. First few questions are worth MORE.

In fact, I know this is true. All the test prep companies make this diagram of the big line up, then big line down and the line gets smaller and smaller. However, I know MGMAT makes a point to show that you will harm your score in the long run at the end because you will have to randomly guess and thus get more wrong. So, I think what this means is that know that they are worth more and just confirm you've got the right answer as opposed to know the answer is B and answer D.

2. You NEED to get a question wrong in order for CAT to begin to even narrow in on your score. I don't know what test taking strategy you can employ from this.

3. You're SUPPOSED to get only 60% right? So people scoring 800 are still getting 60% right? I didn't understand this because my friend said she got all of the quant section right for her to get her 51. Thoughts?

4. 25% of the questions are experimental. My MGMAT instructor says she psyches herself out that when she runs into one she knows she got wrong, she thinks its experimental.

5. Blocks of problems wrong hurt more - From this board, it seems true. I know that MGMAT focuses on the end of the test and that's why there's such a focus on timing.

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by Stacey Koprince » Thu May 21, 2009 2:55 pm
A few comments on the last post.

1. Yes, technically we can think of the earlier questions as "worth more" because there are wider swings in difficulty level there, but as you said, there are severe penalties for running out of time or having strings of questions wrong in a row. So it's not worth it to spend extra time at the beginning - that's the basic takeaway.

2. The strategy you can employ from this knowledge is: I'm going to get stuff wrong. (A lot, in fact.) It's okay to get stuff wrong - it's actually expected! My goal is to make sure that I only get the ones wrong that I should be getting wrong - that I don't get stuff wrong that I really knew how to do. So I let go when the test gives me something too hard, because if I spend way too much time, I know I'm going to get something wrong later in the test - something that I actually knew how to do.

3. The ~60% right rule holds for most test-takers, but not for those at the very top and bottom ends of the scale. Someone at a 750 is probably (note the probably; they don't publish the exact numbers) getting about 75-85% right. Someone at an 800 is getting the vast majority right but still not everything. (Also, just curious: how could your friend know that she got everything right in a section? They don't release that info. And we've all had the experience where we're sure we got something right and we actually got it wrong...)
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by zuleron » Fri May 22, 2009 4:06 am
doclkk wrote:1. First few questions are worth MORE.

So, I think what this means is that know that they are worth more and just confirm you've got the right answer as opposed to know the answer is B and answer D.
I think this is a good approach. I would probably be more inclined to double check the arithmetic on the first few, and double check to see whether I missed any traps. But the absolute max for me would be to spend 2.5 mins on each of the first 10. Again, the aim is with 55 mins left to be starting Q11, but if I am at Q9 with 55 mins left, I will not panic.

I think as you get better GMAT skills, you recognize question types and know how to answer them fairly quickly so your confidence rises to the point that when you pick B, there is usually no need to double check. But I'd still quickly double check for the first 10.

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by Stacey Koprince » Fri May 22, 2009 6:04 am
Just remember - if you do actually spend 2.5m each on the first 10, then you're 5 min behind and you'll have to make that time up somewhere. The best place to make it up is when you see a question that you know is super-hard. Pick something (randomly, if necessary) as soon as you figure out that this one's just too hard. (This is true any time you find yourself behind. If you're not actually behind when you hit something super-hard, then do try to make an educated guess, but don't go over the expected time for that problem - not even a little bit!)

What you want to avoid is saying "oh, I can make up that 5 min by going 30sec faster on 10 questions I think are easier!" and then making careless mistakes. Getting lower-rated questions wrong hurts your score more than getting higher-rated ones wrong.
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by zuleron » Fri May 22, 2009 7:04 am
Thanks Stacey! That is actually my game plan. Try get 7 out of the first 10 correct by double checking (within reason) the first 10. This will mean I'll definitely see some brain-crushers later on in the test, and I will have to have the courage to give up on them in under a minute.

But question: What if you see something super-hard on Q6, do you just randomly guess? I'd be inclined to give it the full 2 mins... what do you think?

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by Stacey Koprince » Fri May 22, 2009 9:09 am
Basically, if I don't know what I'm doing by the halfway mark (1min on quant), then I decide whether I want to make an educated guess or a random guess. If I'm not behind in general, then I spend 30 to 60 seconds trying to eliminate some wrong answers before guessing and moving on. If I am behind in general and need to make up time, then I guess randomly and move on. And, yes, I will do this on question 6 if need be. Maybe I got the first 5 in a row right and 6 is totally a killer!

Also, when making a decision to go over time on a problem, I will go over (up to 30 sec) if I totally know how to do the problem but it's just long or convoluted for some reason and will take a little more time. I do NOT go over if what I'm thinking is, "Well, I don't really know what to do, but I'm sure I'll figure it out if I just spend a little more time..." I know from lots of experience that an extra 30 seconds is not going to magically turn a problem from "I'm not really sure" to "I totally know what to do." And I can't afford to spend more than an extra 30 seconds. So that's the end of that problem - guess (either educated or random, based on whether I'm behind) and move on.
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by zuleron » Fri May 22, 2009 9:56 am
Thanks again for the great tips!