Many of the UPSC CSE candidates break their heads trying to figure out the scaling system done by the UPSC. A lot of candidates who take up maths or science subjects as optionals worry that because of scaling, they stand to get fewer marks than what they should be getting. But the UPSC does scaling only to ensure some level of uniformity in the evaluation. Since there are a lot of subjects involved in the UPSC exam, there tends to be a lot of subjectivity. This article tries to throw some light on the process of scaling by the UPSC in the IAS exam.
The exact process of scaling (normalization) done by the UPSC is not clear. But in simple words, it can be explained as follows. Take a subject like mathematics. It is common knowledge that you can score high marks in this subject (even full marks) compared to a humanities subject like history or sociology. So, the UPSC normalizes the marks obtained by a candidate in this subject to bring parity with students who take history or other ‘less scoring’ subjects. So, if you get an actual score of 450 out of 500, the marks you are awarded would be quite less than 450. But students should not worry unnecessarily about this as even with scaling, they tend to score higher marks in science/maths/engineering compared to the humanities subjects.
You would be amused to know that the UPSC does scaling or moderation even in the IAS prelims exam where all the questions are of the MCQ type. This is done for two reasons: to ease out the variations in the inherent difficulty of the different subjects and also the variations in the difficulty of each question paper in a given year.
Scaling is done in the IAS mains exam for one more reason apart from the two reasons mentioned above. It is to moderate the subjectivity involved because of the examiners. Evaluation by examiners tends to be non-uniform because some examiners are ‘strict’ whereas others are ‘liberal’. (This is not a problem in the UPSC prelims since evaluation is done by scanners and computers.)
The process of evaluation is such that uniform standards are applied to the assessment. There is a head examiner who sets the standards of assessment in the initial stage itself. This is imparted to all the additional examiners. The head examiner periodically assesses the evaluation by the additional examiners to make revisions if necessary.
Apart from this, UPSC also tries to bring about uniformity in the difficulty levels of the 48 subjects offered as optional subjects in the IAS mains exam. According to the UPSC, it indulges in “statistical moderation by linear transformation wherever considered necessary.”
We hope this article clears your doubts regarding scaling by the UPSC. However, we recommend candidates to not worry about this aspect too much. Simply focusing on your IAS preparation will ensure that you crack the exam and also get the desired rank. You can moderate the effects of scaling just by studying really hard!