The Board of Studies (BOS) and University Admissions Centre (UAC) have to do a lot of mathematical modification to your results before your school marks and final HSC exam can be turned into an ATAR. I try to give a brief overview of how they make their adjustments.

Watch part 2 (about moderation): http://youtu.be/J-7qZ6iPZ10
Watch part 3 (about alignment and scaling): http://youtu.be/kZlaqG9t4Qo

For more information, you should check out the BOS explanation of how results are determined: http://www.boardofstudies.nsw.....edu.au/hsc-results/d

You can also have a look at UAC's reports and scaling tables: http://www.uac.edu.au/undergra....duate/atar/reports.s