Universities Admission Index - Calculation in NSW

Calculation in NSW

To calculate the UAI, the UAC used the raw exam marks of the HSC and the moderated assessment mark.

The assessment mark was obtained from the internal school examinations a student sat over the last term of Year 11 and the three terms of Year 12. The school marks were sent to the UAC from the Board of Studies, and from these students were ranked from first to last. The student ranked first was then assigned a moderated assessment mark equal to the highest examination mark scored by that group of students, regardless of who scored it, and similarly the student ranked last would receive the lowest examination mark. The rest of the students had their assessment marks moderated between these two values, with the proportional difference between the marks remaining the same (for instance, the gap of 10 between two marks spread over a range of 20% would be halved if the range was further halved to 10%).

The student who came first in the subject was then assigned the maximum mark, normally 50.0 on a one unit basis but may have changed with scaling. Following that all students who sat the course had a scaled mark calculated based on an estimate of what each student would have achieved had they sat that course. This was repeated for all of a student's units.

The student's two best English units were added along with their next best eight units, which may have included further English units, to give an aggregate mark, out of 500.0. Students were then ranked - however, this rank did not translate directly to the UAI. The distribution of students was uneven. Ranking scaled upwards - only 29.3% of students would receive a UAI of under 50, and the median UAI was around 65, a statistical trend which was applicable at every UAI level. This was because the spread of marks took into account those who did not complete their HSC or otherwise attend the post-compulsory years of education. Their hypothetical marks were determined by the School Certificate, one compulsory for all students in NSW. As their marks were generally lower than those who complete the HSC, they caused the uneven spread across the spectrum of the UAI. Hypothetically, assuming that everyone continued to complete the HSC, the spread would have been completely even. However, NSW retention rates for students stood at around 70%, and there were students who completed the final years without gaining an HSC.