Characterstics of 800 Level question?

[steve.westberg]

How do we determine that 800 level question is there?

In exam be it practice or real, How do we know that any question, if attempted right, will confirm 100th percentile? I mean as we know that overall algorthim in GMAT determine the percentile but in general there are only two category of question; simple and difficult then How do we know that particular difficult question is 800 level?

Let's say in RC of verbal I got two paras one is 30 lines and other is 50 lines. The para with 30 line contains the life story of Abraham Lincoln with simple and more generic questions. The para with 50 lines is about NASA scientists working in a specific project with specifc terms and very deep inference related questions. Now in above example we can clearly say that para with 30 line is of medium difficulty and para with 50 lines is of high difficulty. But how do we know that any difficult question is of 690-700 level or 750-760 level or 790-800 level?

Please post the characterstics of 800 level questions.

[esledge]

This is a good general question; I'm going to move it to the General Folder, as my answer applies to both verbal and quant questions.

First and foremost, the GMAC doesn't rely on relative difficulty (lines of text, types of words used, number of calculation steps) to rank the questions. GMAC puts a question out there and measures what happens.

Difficulty for a question is not just a single number--it is a probability function. The x-axis is "GMAT ability level" (ultimate score) and y-axis is probability of answering the question correctly. Each question has its own curve. For low ability level, the probability of answering correctly is about 20% (corresponding to random selection between 5 choices). The higher the GMAT ability, the higher the probability of answering the question correctly, so the curve slopes up, in sort-of an "S" shape. This is why the GMAT has to test questions in "experimental" status before using them officially: 1000 to 2000 people will answer the experimental question, so that probability of correct answer can be calculated for each question for test-takers in general at every ability level.

The inflection point of the curve (ability below which most people miss the question, and above which most people get it right) is the "difficulty" as most people think of it.

How do we determine that 800 level question is there?

In exam be it practice or real, How do we know that any question, if attempted right, will confirm 100th percentile? I mean as we know that overall algorthim in GMAT determine the percentile but in general there are only two category of question; simple and difficult then How do we know that particular difficult question is 800 level?

When taking the exam, there is simply no way for you to gauge the difficulty of a question with any accuracy. If the GMAC has been doing this for many decades, and they still need all that research to figure it out, how could you possibly know just by looking at a question for less than 2 minutes?

So the practical take-away is this: You can't tell the absolute difficulty of a question, but you can tell how difficult a question is for you. Give every question a fair try, but if you aren't on a path to a solution at 1:30 into it, additional time is unlikely to help. Use the remaining time to strategically guess and move on.

The GMAT probably distinguishes between 760, 770, 780, 790, and 800 by some questions that are at these difficulties...but it's also possible that the 800s just go to the people who make fewer mistakes on the top questions than the people who get 760s do. So whether there are truly 800 level questions or not is pretty unimportant; either way, 800 is tough to get!

[tomslawsky]

So, are they forced to throw out any question with less than a 20% correct rate, as a "trick" question?

[StaceyKoprince]

Nope - that's just a really, really hard question. Only the best will be able to avoid all of the distractions and traps to get to the right answer! :)