You cannot judge a fish's true ability by asking it to climb a tree. Every candidate who appears for CAT is different – different strengths and weaknesses, different accuracy levels, different comfort zones when it comes to time for practice. Thus, to form a good exam taking strategy each student must have a customised preparation/practice programme. This is the reason “Adaptive Practice” and “Adaptive Preparation” are the new buzz words in CAT Preparation. Having read quite a few posts on PG forums, I felt it was a good idea to write about the same.
What does adaptive test practice mean?
Adaptive Practice essentially means that the test and the questions very depending on the responses of the candidate. If you take the GMAT for example (one of the first adaptive exams), if you answer a question correctly, the next question is slightly tougher and has a greater impact on your final score. One the other hand if you answer a question wrong, then the next question would be easier and would have a lower weightage (or in other words would have a lower impact on your final score).
How do you make a test adaptive?
The key is to make a test adaptive is to understand the difficulty level of the candidate on a scale and then deliver questions accordingly. This can be done in two ways – using either Bayesian Probability or by having a large set of questions and a large set of responses for each question (meaning you would be able to calculate the difficulty level of the question based on the number of correct/incorrect responses). Needless to say, the first method is far more difficult to implement and far more reliable.
What are different types of adaptive products?
There are different kinds of CAT preparation products available in the market – let's look at each of them.
Type A Products
You would be asked to give a diagnostic test (or a set of diagnostic tests). Based on the results, the evaluator would know (with reasonable certainty) your weak and strong areas. And then you would be given additional classes for the weak areas. This would also be coupled with difficult tests for the areas where you are strong in (or maybe no special effort) This is not adaptive in the true sense.
This is merely diagnostic/remedial if you may call it so. In case you are strong in a particular area, you are asked to take a more difficult test (remember not a difficult question, but a more difficult test altogether). This is called “single point adaptivity”. There are a fixed number of tests and a fixed set of questions in each test – what varies is how and when I attempt it.
Type B Products
There is no diagnostic test. Each candidate is given a slew of average difficulty level questions and then after the first 2-3 questions the following questions vary depending on the previous response. The next test will start from the same level where you left off the last test. The tests are dynamic in nature. The set of questions I attempt in each test is different. This is “continuous adaptivity”. Since each and every question is dynamically evaluated for its difficulty level (based on the responses received), the candidate does not waste time on an entire test of too difficult or too easy questions. Every question is just right for the candidate.
Is CAT Adaptive?
The CAT exam is not adaptive - at least not in the true sense of the word. But whatever little information is available in the public domain about "normalisation", there is a clear indication that one, there are certain difficult questions as benchmarks, and second, accuracy is highly valued (something that is imitated by an adaptive algorithm).
Which kind of product to pick?
Courses offered by type B institutes would offer faster improvement (because of low wastage of time) and quicker understanding (better analysis because of better algorithm). But because of the dynamically delivered tests, courses offered by type B institutes will almost always be entirely online. Now you need to pick depending on your need as well as what helps you the best.
(Deepak Nanwani is the co-founder of MyPrepMate.com, an online adaptive solution for GMAT and CAT. An alumnus of IIT Guwahati and IIM Bangalore, he is a master strategist for all competitive exams.)