What actually is an ATAR? First of all it's a rank, not a score

The Australian Tertiary Admissions Rank (ATAR) is a number mainly used by universities to select which students, out of high school, will be offered a place in a particular course.

The ATAR is not a score, it’s a rank. If a student gets an ATAR of 80, this doesn’t mean they averaged 80%. It means they performed as well as, or better than, 80% of the other students also graded.

How is an ATAR calculated?

Each state and territory does their own calculation of students’ ATAR. Although differing in certain details, they follow the same principles.

A student must be studying a minimum number of subjects that can be used in the final calculation. The specifics depend on state and territory.

In WA the calculation is based on a student’s four ATAR subjects and the student has to satisfy English competency requirements. In NSW, you have to study at least eight ATAR “units”, of which six have to be what are called Category A, plus two units of English. Category A units are defined as having “academic rigour” and a “depth of knowledge” required for tertiary studies. They include maths, English, science and history, as well as some arts and physical education subjects.

Queensland traditionally used something called an Overall Position, not the ATAR, but is moving to an ATAR in 2020.

Read more: Don't stress, your ATAR isn't the final call. There are many ways to get into university

In most cases, students are marked on how they did in the school assessments that count towards the ATAR. Again, this can differ across states.

In NSW, the assessments that count form part of the Higher School Certificate (HSC). In Victoria, it’s the Victorian Certificate of Education (VCE). In VCE, units 1 and 2 are generally taken in year 11, and units 3 and 4 in Year 12. Units 3 and 4 generally count for the ATAR, but sometimes the first two units also count, such as in some VET programs.

The purpose of providing these examples is to highlight how complicated the creation of an ATAR is and how much it is affected by local factors, including the state or territory you are in.

Using the relevant units, a raw score for each subject is created.

But remember, an ATAR is a rank, so the scores need to be re-interpreted as a rank. Each mark needs to be scaled, which means adjusting it so it can be more fairly compared with the marks for other students and subjects.

Scaling takes into account how competitive, not how difficult, a subject is.

One type of scaling considers where each subject’s mark ranks the student compared to the other students at the same school doing the same subject. Say a student gets 85% for a subject, if the average mark for their class was 90%, they will be ranked lower.

Another type of scaling considers how many students take a subject, and their average marks, compared to other subjects. This is because some subjects have relatively small numbers of students compared to others.

Unfortunately, advice - often on the internet - on how to “game” the system and get a higher ATAR is mostly incorrect. The best advice to ensure your best ATAR is, in the words of one admission centre,

to choose your studies according to what you are interested in; what you are good at; and what studies you need for future study.

What is the ATAR used for?

The main purpose of the ATAR is to determine who gets offered a place in a university course. Think of a queue. When places are limited, the closer to the front of the queue the student is, the more likely they will get in.

Some years there are less people in the queue, or more places in the course. These affect the ATAR required to get in.

Universities sometimes set minimum ATARs, either for a course or the university. So, the student can only apply to the university/course if they achieve this minimum.

A minimum might be set because the university believes this is the minimum ATAR required to succeed. It might also be a way of branding a course, or an entire university, as elite.

It could be a combination of both. And again, because it’s a queue, achieving the minimum still doesn’t guarantee a place.

Universities can and do sometimes make adjustments to its ATAR requirements. This might be due to special consideration - perhaps illness - or because the student received a bonus for studying a language other than English.

For example, for 2019 applicants, Curtin University published advice the minimum ATAR for the Bachelor of Advanced Science (Honours) in Coastal and Marine Science was 95. The minimum selection rank for that course actually ended up being 98.9 – above the university minimum. But at least one student was selected with an ATAR of 94.25 – slightly below the published minimum.

Why is the ATAR contentious?

An ATAR is primarily designed, and works best when it is used, as an efficient way of allocating limited places in a course in a first-come, first-served basis.

But because it’s a rank, it is not a direct representation of a student’s academic ability or potential to succeed in higher education. However, there is a correlation.

Read more: FactCheck: does your entrance score strongly correlate with your success at university?

A recent study by the University Admission Centre found:

the ATAR is the best available predictor of university success[…] The higher the ATAR, the higher the student’s first-year GPA is likely to be.

It also cautioned:

[…] the ATAR is not perfect. There will be instances where the prediction will ‘miss the mark’. Also, there will be cases where selection based on the ATAR alone would not be optimal.

There are always exceptions to the rule that ATAR can predict success. And these exceptions are not just numbers on a spreadsheet but people. For this and other reasons, many would like to see the ATAR scrapped.

But so far, agreement has not been reached on an alternative system that is fairer than the ATAR or as efficient.

In the meantime, it’s important to have alternative pathways to higher education for students who do not have the required ATAR but nonetheless have the capacity to succeed in higher education.