How CAT is scored? Find out the process and the reasons that Prometric and the Indian Institutes of Management selected this scoring method for CAT

Sunday, July 03, 2011

Overview

The Common Admission Test is scored using scientifically proven and internationally accepted techniques which ensure accuracy and fairness. This article explains the process and the reasons Prometric and the Indian Institutes of Management selected this scoring method. More information is available on the CAT  and Prometric websites.

Requirements

In order to expand access to as many candidates as possible, the test design for the CAT must accommodate these requirements:

Fairness

Each submitted test must accurately reflect the performance of the candidate. No external factors, such as the date, time or location of the test, should impact the final score. All candidates must be compared against a common scale.

Convenience: The test must be administered across multiple testing locations, dates and times.

Security: Test content must be protected from exposure and theft.

Solution

In order to meet these requirements, Prometric creates multiple forms, or versions of the paper, and scores them using a multi-step process which ensures that even though each candidate took a slightly different paper, they are evaluated on equal terms.

How does this work?

Step One: The first step in scoring is to calculate the raw score. The raw score is derived by providing candidates with three points for each correct answer and subtracting one point for each incorrect answer. This helps ensure that candidates are only rewarded for what they know and are not awarded points for random guessing.

Step Two: Because versions of the paper are different, some forms may be slightly more difficult than others. If two candidates take different versions of the paper and get the same number of answers correct, it would not be fair to consider them equally capable unless we could prove that each form was equally challenging.  For this reason, the second step of the process involves equating the forms.

A small number of questions are present in more than one version of the paper. These questions allow us to measure how candidates taking different forms compare against each other when asked the same question.  By using enough of these questions across all forms, we can adjust each candidate’s raw score and provide each candidate with the score they would have earned had each candidate taken the exact same form, at the exact same time.

Step Three: The process is completed by placing the equated scores on a common scale. Scaling creates a range of scores which can be used to create a percentile rank for the test as a whole, and for each section. Candidates scoring in the top percentile performed at the highest level when compared to all other candidates.