How do my SACs get scaled?

Do you know what happens to your SAC scores once you’ve been given your mark? Read on to learn more about the (rather complicated!) statistical moderation process that occurs with your SAC scores. Remember that it is the moderated (not raw) SAC scores that are used to calculate your study score.

Why do SACs get scaled?

VCAA (the people who calculate your raw study score) statistically moderates all SAC scores to compensate for differences between schools in SAC difficulty. Each school runs their own SAC for a particular Units 3&4 subject, but this isn’t necessarily fair. SAC scores, therefore, need to be moderated against a common standard.

Firstly, take this example. If I wanted to buy the cheapest iPhone from a trip to the USA, UK and Europe (I wish!), I could collect the following prices:

  • In the USA: US$649
  • In the UK: £539
  • In Europe: €749

How can I tell which place has the cheapest iPhone? We have to convert these to a common scale; for example, Australian dollars.

  • US$649 = $902
  • £539 = $1134
  • €749 = 1108

Now I can tell that the cheapest place to buy an iPhone is the USA. The same kind of conversion to a common scale happens with your SACs! The common scale that is used is called the ‘external score’, which is based on your end-of-year exam and GAT performance.

Your actual SAC score does not matter. Consider two schools which both have four students in a particular Units 3&4 subject:

Pretty Easy High School
External exam grades Raw SAC %Final SAC grade
A+ 100A+
Not-So-Easy High School
External exam grades Raw SAC % Final SAC grade

The raw SAC score is irrelevant to the final SAC score – so it doesn’t matter if your teacher is a harsh or lenient marker. Only the ranking matters (and what the SAC tells you about what skills and knowledge you have, and what you need to work on). Basically, how you (and everyone at your school) performs on the exam will adjust your SAC score.

As I’ve told my Year 12s, if we all get an A+ on the exam, then it’s pretty likely that everyone will get an A+ for their SAC scores, no matter what percentage they get throughout the year.

The next step is to turn your statistically moderated SACs into a VCE Study Score.

Have these tips been useful? If so, we’d love it if you could share or like our post on Facebook, so you don’t need to explain the calculation process to your friends!

ACED wishes you the best VCE exam success!

I've ACED it!

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