Meet the Woman Who Calculates Your ATAR

8 Jun 2018

There was an excellent story in the Sydney Morning Herald last Friday about the process by which the NSW Universities Admissions Centre (UAC) calculates students’ ranks. As well as putting a human face to what has always been seen as an impersonal and robotic process, the article about Dr Helen Tam was also very informative. I would recommend every student in Years 10, 11 and 12 and their parents read it.

The numbers are enormous – 57,000 students in NSW qualify for an ATAR every year and they typically take 27,000 different subject combinations.

The Australian Tertiary Admissions Rank (ATAR) seeks to rank all of these students against each other so that universities can choose who they should offer subject places. Dr Tam says “The ATAR is simply the universities’ way of choosing students most likely to succeed in higher education. It is nothing more than a reflection of a student’s rank in their own year group.”

The ranking process is done by using an algorithm that calculates the average academic achievement of the people taking each course across all their other subjects. Once this has been calculated, students’ raw marks for each course are turned into scaled marks, based on the scaled average. The best 10 units are used to calculate the final ATAR, which is expressed as a number. The highest possible ATAR is 99.95 with roughly 40 students being placed on each 100th of a decimal place. Later, universities publish ‘cut-offs’ for each subject expressed as an ATAR figure.

Both Dr Tam and her predecessor, Prof George Cooney of Macquarie University stress the same messages about choosing subjects for the HSC. This is that, contrary to rumours, students cannot get a better ATAR simply by choosing certain subjects “that scale well”.

Instead, Dr Tam and Professor Cooney suggest a different methodology for picking subjects. Professor Cooney always stressed that students should do subjects which they enjoy, that they are good at and that they are prepared to work hard at. Similarly, in the article, Dr Tam’s advice is to “Forget about scaling,” she says. “Just concentrate on doing your best, and concentrate on learning when you have the opportunity and the time to do so.”

Both also agree that ATAR-predicting websites are not very accurate because they cannot compare students from the right year group. ATARs are calculated by comparing students alongside their peers, rather than on historical data. In this article, Kim Paino from UAC says this about online ATAR calculators, “They use old data – that’s all they can use. They obviously don’t know what the data is going to be for the year ahead – nobody knows that.”

Finally, it is comforting to see that the people who calculate ATARs take their role very seriously and genuinely want the best for every student.

If you have any questions about the ATAR process, please feel free to contact Philip Fielden, the Director of Studies, at school.