The Concept of Relativity

Tech 101 Nov 7, 2017

A dawn in your efforts to discern the labyrinth of relative grading.
By Sriram Ravichandran (B.E Mechanical, 2016-2020)

It was 7:30 pm and the entire hostel was filled with loud voices of men – some crying and some screaming and sounds of phones ringing. Yes, it was the much awaited D-day of every student – the day the results were declared.

”Am I better than him? Or is he better than me? But I prepared better than him. I deserve more than this” – these are some  questions that arise in the minds of many on the day of results, especially in colleges following relative grading system.  Every student wishes to have a good grade in his report card and has the right to know the way it was evaluated and awarded. We, THE BRIDGE, decided to answer few FAQs regarding the grading system followed here and clarify some of the misconceptions .

This is a common question in the mind of every fresher- Is the grading system followed at PSG Tech any different?

Well, PSG Tech has a unique way of grading system which is called ‘RELATIVE GRADING’. In this system, the grades are awarded to the students based on their performance relative to others in theory courses having Continuous Assessment and Final Examination (which is basically the semester exam). So, scoring high grades is not only a function of one’s cognitive ability, it also depends on his/her relative standing in the class.

So, how is grading done in this system?

Initially, for each theory course, the total mark M [ i.e. the sum of CA and FE] is computed for every candidate. The statistical parameters Mean (µ) of marks obtained by all students(in that particular class) who have passed in that particular course and Standard deviation(σ) of the distribution of marks of the former are as follows:

\[µ = \frac{\sum_{i=1}^n M}{n}\]

\[σ = \sqrt{ \frac{\sum_{i=1}^n{{(M_{i} – µ)}}^{2}}{n}}\]
Here, n =number of students who appeared for the examination in that particular course.
Mi = total mark of ith student in that course

After calculating the required mean and standard deviation, the respective grades are generally allotted according to the following intervals:

[table id=5 /]

Thus, the level marks are set accordingly and the respective grades are granted.

(P.S. Don’t chide me for too much usage of mathematics here)

Just like all other systems, this system also has some exceptions. If the score is below 80%, ‘O’ Grade cannot be granted . If the maximum marks awarded in a course is greater than or equal to 95% and if the number of candidates securing ‘O’ grade is less than 7% of the total number of candidates, then some candidates with A+ grade may be awarded with ‘O’ grade. In such cases, some candidates having ‘A’ grade may be awarded with A+ and so on…

This is an attempt to push students to achieve better standards without jeopardizing their grades.

Finally, the Performance Analysis Committee chaired by our esteemed principal, consisting of Controller of Examinations and all Heads of Departments will, by collective wisdom, normalize the marks secured by students and would ensure that students are graded in a reasonable manner.

Among whom is relative grading done? i.e. Scores of which group of students affects a person’s grade?

Well, some say that scores of all students in a department are taken into consideration which is not always true. According to the recent data obtained by us, the scores of students who are lectured by the same faculty are taken into consideration, irrespective of the department.

For example: If professor X gives lectures in department Y consisting of 70 students and in department Z consisting of 60 students for the same course/paper , then the scores of the entire 130 students is taken into account for calculating mean and deviation.

So, are all the subjects or papers graded relatively?

As the main aim of relative grading is to compare students on a common ground and to provide them equal opportunities to score high, this grading system is not followed when the aim is not fulfilled. For instance, absolute grading system is used rather than relative grading for all laboratory or practical papers. This is done as each student may get different experiments during their lab exams and it would be unfair to grade them relatively under such circumstances.

How exactly do grades of other students influence one’s grades?

There is a common misconception among students that one’s grades would always increase if the performance of students in his/her class is very low. Well, this is not always true. For instance, if 20 students fail in a class of 100 students then, only 7%* of the remaining 80 students will be assured of an ‘O’ grade (approximately 5 students*), whereas if all pass then 7%* of the entire class (100 students) will be assured of an ‘O’ grade ( 7 students*). This condition applies for other grades too. Thus, as the number of failures increases the probability of students scoring high grades decreases. This system makes the faculty to concentrate on low scoring students, thereby maintaining the standards of entire batch equal. Thus, it is the difficulty of the paper that actually influences the grades and not the performance of others always.

( * represents the minimum value )

Is the difficulty level of scoring a particular grade at PSG Tech the same as at any other institution? (or) How competitive is a GPA acquired at PSG Tech, with the same obtained in some other institution?

This is a critical question which might have various answers. Before answering it, we must understand that relative grading is not something new which is followed only at PSG. Many other prestigious institutions, from IITs and VITs to Harvard university, all follow the same system of evaluation. Hence, the grades obtained here are comparable to any other top institution’s in our country. But as the level marks for grades vary drastically from one institution to another, the comparison cannot be done numerically and this is one of the reasons why many companies consider various parameters other than GPA for placements.

Renowned journalist Malcolm Gladwell once said, “In a class full of Einsteins, relative grading would amount to some of the Einsteins getting 10, some of them getting 6, and some of the Einsteins failing.

Thus, students must believe in themselves and in their abilities and not feel low when their grades go low. For those who want to frame strategies to learn better and score more but are unable to do so, there is a popular saying – “There are strategies to score or to be ahead but there is one strategy to learn which is curiosity.

The master of ‘Theory of relativity’ once said “Curiosity has its own reason for existing”. I think, he was talking about the curiosity of learning, not scoring. Ain’t I right?

SRIRAM RAVICHANDRAN (B.E Mechanical,2016-2020) is enthusiastic and has an inquisitive mind set. He is keen on understanding the world and keeps a constant update on engineering sector. He is an elocutionist and was a member of “THE BAIT” debate club.
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