Analyzing Your Practice Tests, Part 2

by , Feb 28, 2011

Welcome to part 2 of our updated process for analyzing your practice tests. As we discussed in yesterday's first half , were basing the discussion on the metrics that are given in ManhattanGMAT tests, but you can extrapolate to other tests that give you similar performance data (note: you need per-question timing and difficulty level in addition to percentage correct/incorrect data).

Last week, we discussed how to assess the data provided in the question list the line-item list of the questions that you received and your performance on each. This week, were going to interpret the analysis given in the Assessment Reports.

In the ManhattanGMAT system, click on the link Generate Assessment Reports. Run your first report based solely on the one test that you just did; later, well aggregate data from your last two or three tests.

The first report produced is the Assessment Summary; this report provides the percentages correct for the five main question types, as well as average timing and difficulty levels. Problem areas are indicated by:

  • percentages correct below approximately 50%, especially when coupled with lower average difficulty levels (though I'm not worried if I see, say, 48% correct with an average difficulty level of 730 - that's a good result unless youre trying to score 760)

  • average timing that is 30 seconds (or more) higher or lower than the expected average

  • a big discrepancy (more than 30 seconds) in average time for correct vs. incorrect questions of the same type; its normal to spend a little extra time on incorrect questions (because those are probably the harder ones!), but not a ton that just means youre being stubborn

Next, if I think there is or might be a timing problem, I take a look at the second and third reports (by Question Format and Difficulty). These two reports (one each for Quant and Verbal) tell me my performance based upon the difficulty levels of the questions.

In these two reports, Im looking for:

  • average timing that is 30 seconds (or more) higher or lower than the expected average, and whether that is happening on correct or incorrect questions (or both)

  • lower percentages correct on lower-level questions than on higher-level questions

In particular, these two things might appear together. If that happens, I might be spending too much time on incorrect higher-level questions and not enough time on lower-level questions that Im then getting wrong as a result. The data here can help me to uncover that problem.

Note: the timing averages for Reading Comprehension can be misleading because the first question for each passage includes the time to read the passage itself. For Reading Comp, you need to dive back into the problem list to look at each problem individually in order to get a true picture of what happened.

Finally, I want to look at the fourth and fifth reports (Quant by Content Area and Topic, Verbal by Verbal Type and Topic). Before I do this, though, I may decide to run the reports based on my last 2 or 3 tests rather than just my last test. Were diving deep into the details with these final two reports, so there will be lots of categories with only one or two questions unless we add more data to the report.

If you took another test relatively recently (within the last few weeks), then its a good idea to add that test to the mix at this point. You may also decide to look at these last two assessment reports based just on the last test first, and then run the reports again using your last two tests your choice. If you use only one test, be aware that your analysis may need to be flexible for those sub-categories with only 1 question. If you get 0% of 1 question right, that doesnt mean that area is a big weakness!

The fourth and fifth reports show all of the questions broken out by question type and sub-type or sub-topic. In general, Im going to split everything into one of five categories:

Group 1. I get these right roughly within the expected timeframe (>50% right and neither way too slow nor way too fast).

These are your strengths. Going forward, theyre not high on your priority list, but there may still be things you can learn: faster ways to do the problem; ways to make educated guesses (so that you can use the thought process on harder problems of the same type); how to quickly recognize future problems of the same type. Also, make sure that you actually knew what you were doing for each problem and didnt just get lucky! Finally, you may want to move on to more advanced material in these areas.

Group 2. I get these wrong roughly within the expected timeframe (<50% right and neither way too slow nor way too fast).

These indicate a possible weakness in content or methodology, but check the difficulty levels perhaps you just happened to get a couple of really hard ones in the same category.

First, you need to figure out why you got each question wrong. If it was 700+, you got another lower-ranked question of the same type right, and you were fine with these on your last test, then your fundamentals may be good, and it may be time to lift yourself into the toughest areas for this particular question type or content area.

Alternatively, maybe you did know the material but you made careless mistakes. You might need to add these questions to your error log (click here for more on error logs).

Finally, something in this category may indicate a fundamental weakness. Is the material something you already studied or something you should know? Return to it. Have you not studied it yet? Time to start. Is the material commonly or rarely tested? Prioritize the commonly tested material first. As needed, return to the relevant sections of your books.

Group 3: I get these wrong way too quickly (more than 30 seconds faster than expected)

Are these really weaknesses or were you just going too fast (and, naturally, making more careless mistakes)? Why were you going too fast on these?

If you chose to rush because you knew you didnt know what to do (in other words, you made a guess and moved on), thats fine. Decide now whether you want to study this area further.

If you chose to rush because you thought it was easy and then you made a careless mistake, add these to your error log as well. And remind yourself not to sacrifice a correct answer just to save 30 seconds!

Alternatively, if you sped up because you were worried about time, then you need to fix your timing problems elsewhere in the section.

Group 4: I get these right way too slowly (more than 30 seconds slower than expected)

These are still weaknesses; it doesnt matter that youre getting them right! Theyre costing you points elsewhere in the section possibly more points than you earned by getting the too-slow ones right.

Figure out why the timing is higher and how you can do these more efficiently. If the timing is just a little bit too high on one problem of that type, that may be okay perhaps the problem is extra hard and long. If you're consistently going long, however, then perhaps you don't know the best way to solve the problem, in which case (a) figure out the best solution, or (b) the best way to recognize that this problem requires a certain set of steps, or (c) both. Also realize that, sometimes, the solution is simply to guess faster and move on. Sometimes, it's better to get something wrong in 2 minutes than right in 4 minutes (because of the eventual consequences).

Don't forget to make sure that you really did know what you were doing on the ones you got right; if you got lucky, then move questions from this group to group 5.

Group 5: I get these wrong way too slowly (more than 30 seconds slower than expected)

These are the biggest weaknesses, obviously. Get them wrong faster. Seriously - you're getting them wrong anyway, so start by just taking less time to get them wrong! Use that time on questions from one of the other groups, where additional time is more likely to make a difference.

What is slowing you down? Figure that out and it will tell you what to do next. You may need to review the material from your books, or do more practice with problems of this type, or find more efficient ways to solve, or learn better how to recognize questions of this type, or be more quick to make an educated guess and move on.

For all of the above, dont forget to think about the frequency with which the material is tested. If something is a great weakness of yours but is not frequently tested, then make that a lower priority than something that is a medium weakness but is really tested a lot. (If youre not sure what is more or less frequently tested, get onto the forums and ask.)


(1) Its critically important to evaluate your performance across all three main axes at once percentage correct, timing, and difficulty. Its not enough to look only at percentage correct. A timing weakness is as much of a problem as an accuracy problem perhaps more. If your timing is bad enough, that can kill your accuracy.

(2) Split out the data into the 5 major groups described above. Groups 2, 3, and 4 typically represent your biggest oportunities to improve (though that doesnt mean you should ignore groups 1 and 5).

(3) Use the forums! When you discover certain weaknesses, present the data on the forums and ask teachers for their advice about how to remedy those weaknesses. Post specific problems, discuss what you did, and ask for advice about how to solve (or how to solve more efficiently), how to guess more effectively, or whatever is relevant for you.