What is the 'percentile' of exam scores and what does it mean?

For the first time, the Ministry of Education and Training announced the percentile of 7 university entrance exam scores. So what is the percentile and what does it mean?

Associate Professor, Dr. Bui Hoai Thang - Head of Training Department, University of Science and Technology (Ho Chi Minh City National University) - answered questions from parents and students at the 2025 Choice Day organized by Tuoi Tre newspaper - Photo: TTD

According to Associate Professor Dr. Do Van Dung - former principal of Ho Chi Minh City University of Technical Education, percentile is a statistical concept that helps determine the relative position of an individual in a group based on scores or measurement values.

With composite scores, instead of just looking at the absolute score, percentiles show how a candidate "ranks" compared to the entire group of participants.

Mr. Dung commented that this year English is difficult, so the combined exam score of math - physics - chemistry is higher than math - physics - English or math - literature - English. If all candidates in these three groups are considered with the same standard score, candidates taking A01 and D01 will be at a disadvantage compared to A00.

With this percentile, candidates know how much their score is equivalent to the score of other groups. Universities also know the scores of candidates according to the groups and have a way of selecting and setting the standard score to suit that difference.

For example, a candidate with combination D01 has a score of 23, looking at the A00 score spectrum, the D01 score is lower, the candidate does not dare to register for admission. However, with the percentile of the admission combinations just announced by the Ministry, it can be seen that 23 points of D01 will be equivalent to 25 points of A00.

With the same percentile but different scores, these two candidates are considered to have similar abilities because they are both at the 91st percentile.

The candidate's percentile is at position 91, which means he is in the top 10% of candidates with the highest test scores in the admission groups, even though his test scores are lower. Thus, the candidate knows where his test score is in relation to other groups.

Top 10% of candidates with the highest test scores (from 90th to 100th percentile) - Screenshot

Suppose there are 100 candidates taking the exam and the candidate scores at the 90th percentile. This means that the candidate's score is higher than 90% of the remaining candidates, with only 10% of the candidates scoring higher. Conversely, at the 50th percentile, the candidate is at the average level, higher than 50% of the candidates.

This method does not rely on absolute scores, but focuses on the score distribution of the entire group, which helps to evaluate more fairly, especially when scores can fluctuate due to the difficulty of the test.

In layman's terms, percentiles can be thought of as a "ranking scale": not only does a high score win, but also how a candidate ranks relative to other candidates.

This is more beneficial for candidates in determining their major, as well as their chances of being admitted to the desired university.

This is also the basis for converting test scores to assess ability and thinking on a 30-point scale, in order to determine that scores from different exams have equivalent value when considering university admission, avoiding the situation where one test is easier, leading to unfairness.

When converting, it will be based on statistics of corresponding score ranges according to percentile levels (for example: top 0.5%, top 1%, top 3%, top 5%, top 10%...).

For example, if a candidate's score is at the 95th percentile in the aptitude test (meaning the top 5%) it will be converted to the equivalent score at the 95th percentile of group A00 in the high school exam.

Divide the test score into 100 equal parts

To calculate the value in converting test scores, education expert Sai Cong Hong said that some commonly used score conversion methods are: linear conversion, percentile, z-score, classification, and statistical simulation.

Usually for tests with differences in difficulty or score distribution, people use the percentile method to convert scores (percentile is a way to convert scores using the percentile method), dividing the data into 100 equal parts, each part representing 1% of the total data.

With the percentile method using percentiles, a sample of several thousand or more is needed to help the results reflect most accurately.

However, Mr. Hong also said that only data from candidates taking both exams should be used to build a percentile conversion table.

Absolutely do not use the distribution of all candidates in each block separately. That can easily lead to serious errors in score conversion and cause unfairness in admissions.

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Source: https://tuoitre.vn/bach-phan-vi-diem-thi-la-gi-y-nghia-ra-sao-20250723103324949.htm