SSC adopts new method of normalisation of scores in recruitment exams

New Delhi: The Staff Selection Commission (SSC) has adopted a new method of normalisation of scores in different recruitment examinations conducted by it.

In an explanatory note, it said when candidates take exams in multiple shifts, the difficulty level of each shift might vary -- some could be harder or easier than others.

"To make sure everyone is treated fairly, the Commission normalises the scores. This means that the scores are adjusted so that candidates from different shifts can be compared fairly on the same scale," it said.

According to the earlier method of normalisation, this was done by considering the top scores and average scores from all shifts, as well as how much scores vary within each shift, the SSC said.

"Using this information, a new, adjusted score for each candidate was calculated. This new score shows how well a candidate performed compared to everyone else, not just those in his/her own shift. This process of normalisation is effective at ensuring that candidates who took tougher shifts aren't unfairly disadvantaged, and everyone's scores can be compared fairly, no matter which shift they appeared in," it said.

After evaluating the impact of normalisation, the SSC has adopted a new procedure of normalisation based on the equipercentile method.

The details of this method have been published on the website of the commission vide its notice dated June 2.

Under the equipercentile system, instead of adjusting scores using averages and variation (spread), the ranks or percentiles of the candidates in each shift are considered, the SSC said.

According to this system, the most important determinant of a candidate's performance is his ranking within his own shift, which is reflected by the percentile score.

For example, a candidate who scored better than 80 per cent of the examinees in one shift will be matched with a candidate who scored better than 80 per cent examinees in another shift, the commission said.

By matching candidates based on their relative positions in their own shifts, this method creates a fair way to compare scores across different shifts, even if the difficulty varies, it added.

"Thus, the new method ensures that candidates who faced certain problems relating to content in one shift won't be unfairly ranked compared to candidates in other shifts who didn't face similar problems," the SSC said, adding that it will continue to work towards improving the systems so as ensure the sanctity of the examinations conducted by it.