In this blog article, I’d only like to talk about the IIMs’ scoring system for boards examinations and graduation marks. The fact that they consider a heavy weightage for the marks obtained in boards examination as compared to the CAT score is another contentious issue which I’d like to discuss some other time.
A rough pattern of weightage of various marks for any IIMs’ scoring system looks something like this:
CAT marks: 60%
Xth: 10%
XIIth: 10%
Graduation: 10%
Work Experience: 10%
The score given for marks obtained in boards and graduation is a step function defined as: Score = 10 for %age=< 100 and >= 95, Score = 8 for %=<95 and >90 , and so on)
Here, I’d like to compare two candidates A and B. The differences between their percentages in boards and graduation is small and A has performed better than B in the CAT exam.
Suppose candidate A has secured 264/450 (A percentile of 99.85 overall) in CAT, 89.6% in Xth, 79.4% in XIIth, 84.2% in graduation and no work experience. On the other hand, candidate B has secured 253/450 (A percentile of 99.54 overall) in CAT, 90.4% in Xth, 80.8% in XIIth, 85.6% in graduation and no work experience.
In this case, IIMs calculate the score from the CAT exam by linearising it through the following equation:
Score = (Cat score / 450) * 60
This gets A 35.2 + 6 + 2 + 4 + 0 = 47.2/100, while it gets candidate B 33.73 + 8 + 4 + 6 + 0 = 51.73/100.
Instead of this, had the IIMs linearized the scoring system for boards as follows:
Score = (percentage – 75) / 2.5,
A would’ve had a total of 35.2 + 5.84 + 1.76 + 3.68 + 0 = 46.48/100, while candidate B would’ve got 33.73 + 6.16 + 2.32 + 4.24 + 0 = 46.45/100.
The candidate B is helped by the fact that his percentages are on the right side of the percentage range while candidate’s A percentages fall on the wrong side. As we see, unlike in the first case with the final score difference between A and B is huge, the first case makes their score comaparable. Hence, when we linearize both the CAT scores and boards, graduation percentages before adding them up, it gives us far more just results.
Also, it is a known fact that boards across the country are far from uniform in their scoring. So, it makes very difficult for a person from, say Rajasthan board to compete against a person from Andhra Pradesh State Board.
This faulty and unjust system has surely robbed a lot of candidates who did extremely well in CAT the chance of getting into and IIM. Since my marks in boards and graduation are similar in manner to candidate A and the fact that I can't go back to my past and write the board exams again or work harder for my cgpa, I don’t think I am going to write CAT again, knowing the fact that the top IIMs are always going to elude me.
[Certain data used in this blog post is based on the scoring criteria released by IIM C and IIM L.]
