THE Board of Intermediate and Secondary Education (BISE), Lahore, is incorrectly using statistical terms like ‘percentile score’ and ‘relative grades’ instead of mathematical notations ‘percentage’ and ‘absolute grades’ in the online mark sheets/academic transcripts of its matriculation results announced on Sept 19.

Percentile scores and percentages are altogether two different terms, but perhaps owing to lack of understanding, the board is using both terms as synonyms for each other.

A percentage is a number or ratio expressed as a fraction of 100, while a percentile is a term used in statistics to express how a score compares with other scores in the same set of data.

The percentile score is typically communicated as the percentage of values that fall below a particular value in a set of data scores.

To elaborate, suppose there are 100 students in a class taking a test of 100 marks. If a student gets 80 marks out of 100, the percentage marks of the student will be 80pc.

If the marks of 90 students are less than the student who got 80pc, the percentile score of that particular student will be 90. However, if the student who got 80 marks is the top scorer, his percentile score will be 100 with 80pc marks.

Similarly, relative grades and absolute grades are entirely different terms. Relative grades are based on percentile score, while absolute grades are calculated with percentage of marks obtained by students. The grading system will be an absolute grading system if it defines that all students who get, for example, 80pc in any subject, will be given A grade. On the other hand, the grading system will be a ‘relative grading system’ if it determines that all students who get, for example, percentile score of 80 in any subject, will be awarded A grade.

All intermediate and secondary education boards practise absolute grading systems wherein the grades are determined on the basis of percentage marks. The BISE, Lahore, should take note of these anomalies.

Madeeha Rafi
Gujrat

Published in Dawn, October 21st, 2020