How to Analyze an IR Graph Problem

by on September 5th, 2012

This is the latest in a series of “How To Analyze” articles that began with the general “How To Analyze A Practice Problem” article (click on the link to read the original article). This week, we’re going to analyze a specific IR question from the Graph prompt category.

Let’s try out the question: here it is. Just in case that link changes, you can also click on this link to go to the website, and then, about halfway down the page, click on the “Graphics Interpretation” link. We’re going to try the 2nd of the 4 questions. If you’re going for an average IR score, give yourself 2.5 minutes; if you’re going for a really good score, give yourself between 1.5 and 2 minutes.

Note: when you are done, do NOT click the “next” button. Just leave it up on the screen and come back here.

First, read the complete solution to the problem. In that article, I discussed how I was able to answer one of the questions correctly even though I wasn’t 100% confident that I understood part of the description of the graph. I also talked about an important lesson I learned regarding how to read the questions.

In other articles in this series, I’ve pretended that I answered the question incorrectly. In this one, I’m going to give you my actual analysis from when I did the problem.

1. Did I know WHAT they were trying to test?

- Was I able to CATEGORIZE this question by topic and subtopic? By process / technique? If I had to look something up in my books, would I know exactly where to go?

The question is an IR Graph prompt. The question prompt is pretty distinctive: there’s a graph and two sentences with “fill-in” blanks.

- Did I COMPREHEND the symbols, text, questions, statements, and answer choices? Can I comprehend it all now, when I have lots of time to think about it? What do I need to do to make sure that I do comprehend everything here? How am I going to remember whatever I’ve just learned for future?

I got the question right in a reasonable amount of time. Even so, there are still some things I can learn from this one.

- Did I understand the actual CONTENT (facts, knowledge) being tested?

I struggled with the second sentence of the graph description. It said:

“In the leftmost column grouping, the Precambrian eon is subdivided into chronometric eons shown on the far left; but otherwise, in the rest of the graphic, each subsequent column to the right shows the subdivisions of the timeframes to its left.”

As I mentioned in my original write-up of this problem, I read that sentence twice when I first did this problem, and even then, I still felt like I was missing something. I was fine with the first half; despite the “big” vocab words, the first half just says that the leftmost column is divided into certain time periods (eons). The “but otherwise, in the rest of the graphic” language confused me, though. “But otherwise,” to me, means “I’m about to tell you something that’s totally different.” The other two graphs, though, also show various categories split up by timeframes… so why the ‘but otherwise” language?

I didn’t figure this out while the clock was still ticking. After reading it twice, I finally just shrugged my shoulders and continued to solve. It turned out fine – I answered the question correctly, after all – but this was still bugging me so I spent some time afterwards trying to understand it better.

I finally realized that the “but” contrast language was just to indicate that the two graphs to the right are not using the same overall timeframe as the first one; rather, each shows a subset of the graph immediately to its left. The confusing language of the second sentence made me feel like I wasn’t getting it, but I did actually understand how the graph worked.

2. How well did I HANDLE what they were trying to test?

- Did I choose the best APPROACH? Or is there a better way to do the problem? (There’s almost always a better way!) What is that better way? How am I going to remember this better approach the next time I see a similar problem?

I had a small bobble on the first question but it taught me a very important lesson. I read the first sentence without looking at the possible answer choices and then tried to go back to the chart to figure out the answer – again, without looking at the answer choices. I realized that I didn’t even know what kind of answer I was looking for… “closest to” what? An era? An epoch? Nope, turned out to be a number: closest to a certain percentage of something else.

Clearly, I need to develop the habit of looking at the answer choices when I first read the “fill in” sentence. On the first question, this lesson is reinforced by the fact that the three answer choices are so far apart. No actual calculation is necessary; we can estimate to get to the answer.

- Did I have the SKILLS to follow through? Or did I fall short on anything?

I didn’t have any problems with the minor amount of math involved.

- Did I make any careless mistakes? If so, WHY did I make each mistake? What habits could I make or break to minimize the chances of repeating that careless mistake in future?

- Am I comfortable with OTHER STRATEGIES that would have worked, at least partially? How should I have made an educated guess?

- Do I understand every TRAP & TRICK that the writer built into the question, including wrong answers?

On the first one, estimation (which is an educated guessing strategy) is actually enough to get all the way to the right answer. For the second one, I could imagine that people might get tangled up in the language, especially if they were struggling to understand the graph. The words I’d key in on are “the onset of a new eon, era, and period.” How does the chart indicate a new eon (or era or period)? Right, a horizontal line and a new name for the new eon (or era or period) that then begins.

Glancing at the locations of the other answers, I realize that both the Triassic period and the Pliocene epoch border horizontal lines that cover at least two categories (era and period for the Triassic and period and epoch for the Pliocene). I think that’s why they included these two in the answer choices – they’re traps. Neither, though, spans all three categories (eon, era, and period) that were mentioned in the question. So my lesson here is to be very careful about what they say: they mention three categories, so two isn’t good enough and that’s enough reason right there to cross off Triassic and Pliocene.

3. How well did I or could I RECOGNIZE what was going on?

- Did I make a CONNECTION to previous experience? If so, what problem(s) did this remind me of and what, precisely, was similar? Or did I have to do it all from scratch? If so, see the next bullet.

- Can I make any CONNECTIONS now, while I’m analyzing the problem? What have I done in the past that is similar to this one? How are they similar? How could that recognition have helped me to do this problem more efficiently or effectively? (This may involve looking up some past problem and making comparisons between the two!)

- HOW will I recognize similar problems in the future? What can I do now to maximize the chances that I will remember and be able to use lessons learned from this problem the next time I see a new problem that tests something similar?

I learned a really important lesson. Looking at the answers before starting to solve will help me on all questions of this type going forward. Good thing I took the time to analyze this one, even though I answered it correctly within a normal timeframe!

Note that, of course, the details above are specific to each individual person – such a write-up would be different for every single one of you, depending upon your particular strengths, weaknesses, and mistakes. Hopefully, though, this gives you a better idea of the way to analyze an IR problem. This framework also gives you a valuable way to discuss problems with fellow online students or in study groups – this is the kind of discussion that really helps to maximize scores.

* GMATPrep® question courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

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