CAT 2015: Percentile calculation formula decoded; know how to calculate sectional and overall scores

After appearing in a fully revamped CAT 2015 exam on November 29, 2015, the test takers have been registering on many websites to get the glimpse of their percentile. All of them claim to be nearly accurate but none of the percentile predictors share how they have arrived at the percentile score of the candidates based on their attempts in CAT 2015 in different sections.

This confusion persists although CAT 2015 website claims to have the most transparent process on score normalization and calculation of percentile. A bit of information on score normalization process in CAT 2015 is also available on CAT website. The process claims to focus on Fairness, Equity and comparison of performances across both the test sessions in CAT 2015. But the Normalization process has only scanty details which may not bring home the clear picture of percentile calculation formula in CAT 2015.

Scoring process claims transparency CAT Centre 2015 has declared In order to ensure fairness and equity in comparison of performances of the candidates across different test sessions, the scores of the candidates shall be subjected to a process of Normalization. The Normalization process to be implemented shall adjust for location and scale differences of score distributions across different forms and the scaled scores obtained by this process shall be converted into percentiles for purposes of shortlisting.

GATE pattern followed On the question of transparency of normalization process across the multiple sessions CAT Centre 2015 states The process of Normalization is an established practice for comparing candidate scores across multiple Forms and is similar to those being adopted in other large educational selection tests conducted in India such as Graduate Aptitude Test in Engineering (GATE).

Now to understand the score normalization process in CAT 2015, you are supposed to understand first the GATE process which stands a bit changed. Those appearing in GATE or have understood the process can understand it better but for those who are unaware about the process have to understand the GATE process first. In fact the commerce, science, medical, paramedical and graduates in Humanities who appeared in CAT 2015 still remain oblivious of the percentile calculation formula in CAT 2015.

GATE normalization process During 2015, the CE, CS, EC, EE and ME examinations are conducted in multiple sessions. Suitable normalization process is therefore applied to take into account any variation in the difficulty levels of the question sets across the different sessions. The normalization is done based on the fundamental assumption that in all multi-session GATE papers, the distribution of abilities of candidates is the same across all the sessions.
According to the GATE committee, this assumption is justified since the number of candidates appearing in multi-session subjects in GATE 2015 is large and the procedure of allocation of session to candidates is random. Further it is also ensured that for the same multi-session subject, the number of candidates allotted in each session is of the same order of magnitude.

Application of formula in CAT 2015

The formula to calculate the percentile in CAT 2015 can be devised. At MBAUniverse.com and Vista Mind experts have been working and have decoded the pattern of normalization and calculation of percentile in CAT 2015. The score normalization process formula, as understood by Ankit Jindal, CAT expert would be as follows

Expect high percentile with good scores The above score is supposed to fetch a percentile near about 99.05. On the similar note and going by the relative difficulty level across the both sections in CAT 2015 examination, it is expected that CAT 2015 takers could score a higher percentile in than they could score in earlier CAT exams.

In CAT 2015 sections were found moderate and more balanced. More options to attempt the questions were available. A candidate could crack 70 correct out of 100 in CAT 2015 but it was much difficult to crack 35 correct out of 60 in earlier CAT exams despite the fact that more time per question to solve was available in earlier CAT exams.

Besides the introduction of 28 Non-MCQ type questions without any penalty for wrong answers, it is expected that the candidates would score high and would record higher percentile.

Earlier all the questions used to be of MCQ type and due to negative marking system the percentile got dipped low in earlier CAT exams. In CAT 2015 with more questions available most of the candidates who refrained from attempting doubtful and difficult type of questions can expect a high percentile.