HSC Scaling and Its Importance

HSC scaling is a popular topic to HSC students andHSC. In order to quantitatively compare the
parents, and is often an area that is commonlyscaling  effect of different courses, you will need
misunderstood. Scaling is important as it affects allto get familiar with reading statistics published by
students aspiring to get into university after theUAC. The rest of this article will highlight the
HSC.important things to note.
Scaled marks versus HSC marksReading 'scaled means'
A commonly misunderstood concept is theFirstly, what are 'scaled means'? The scaled mean
relationship between HSC marks and scaledfor each subject is the average scaled mark
marks. HSC marks are the marks the Board ofreceived by all students who took that subject
Studies awards you, and appear on your Recordfor that year. For example, in 2008, the scaled
of Achievement. These marks determine whichmean for Maths Extension 2 was 43 out of 50.
performance band you fall in (e.g. Band 6 or E4)This means that among the Maths Extension 2
for each of your HSC subjects. These marksstudents in 2008, the average of their scaled
measure how well you did according to themarks was 43 out of 50. This subject has
subject's requirements. E.g. if you received a Bandtraditionally been one of the highest scaled
6 in English Advanced, it means your performancesubjects available for the HSC. In terms of
satisfied all the criteria required by the HSC Englishreading these scaling statistics, generally the higher
syllabus to achieve a Band 6. However, in anythe scaled mean, the higher the scaling effect.
year, any amount of HSC students can get aEach year, the UAC publishes a scaling report
Band 6. For example, in a particularly smart year,which contains important scaling statistics for all
a higher proportion of students may receive BandHSC subjects eligible to contribute to a UAI. For
6 in English Advanced. It is not how well you do inmore information, read about UAC scaling
your subject, but rather, how well you do relativestatistics. In the report, there is an important
to other students which determine your UAI.section called Table A3, which is a table setting
Here's where your scaled marks come into play.out the scaled means of all subjects.
Your scaled marks will NOT be shown to you atTo illustrate the effect of scaling, in 2008, a Maths
the end of your HSC, as you will only be shownExtension 2 student only needs to be in the top
your HSC marks (aligned marks, to be precise).46% out of all Maths Extension 2 students to get
Ironically, it is your scaled marks which are thea scaled mark of 45 out of 50 (or 90/100). A
most important determinant to your UAI. ScaledMaths (2 unit) student would need to be in the
marks are calculated by the UAC (not the BOS)top 3% out of all Maths (2 unit) students in order
under a totally different process. Basically, theseto achieve the same result. These facts are read
marks measure your performance relative tooff the UAC scaling report. In the 99th percentile,
other students. (For a more technically accuratea Maths (2 unit) student receives a scaled mark
discussion on scaled marks and what they mean,of 46.1 out of 50. In the 75th percentile, a Maths
as well as the mathematics behind UAI calculation,Extension 2 student receives a scaled makr of
please read our article on the mechanics of46.2 out of 50. Arguably it is easier to be above
scaling) Remember, your HSC marks are aaverage in Maths Extension 2 than to be near the
measure of how well you did in your subject, buttop of the state in Maths (2 unit). This is the main
your scaled marks measure how well you didbenefit derived from choosing high scaling
relative to other students. It is your scaled markssubjects.
which are used to calculate your UAI, not yourEffect on UAI calculation
HSC marks.Simply put, the higher the total of your scaled
Through the process of scaling, the UAC convertsmarks, the higher your UAI will be. Sometimes
your raw examination marks (the actual markswhen students choose subjects with lower scaled
you received in your external and moderatedmeans, do spectacularly in their HSC (e.g. receive
internal assessment) into scaled marks.TheseBand 6 for all of their units) but receive a UAI
scaled marks are then added up to arrive at yourthat is lower than what they had expected.
aggregate mark (students refer to this as yourFor example, if you did English Standard, IPT,
'aggregate') out of 500. The UAI is simply aLegal Studies and Biology, and scored 90 in all of
percentile rank of your aggregate, which is theyour subjects, your UAI would be around 94 in
total of your scaled marks in your top 10 units.2008. While this is in no way a poor UAI, if you
How can knowledge of HSC scaling help me?received the same HSC (aligned) marks for
Understanding the process allows you to plan yourEnglish advanced, Maths Extension 1 &
HSC, to an extent, in such a way as to make2, Chemistry and Physics, your UAI would be in
scaling work to your advantage. For example, ifthe vicinity of 99. Again this is because of the
you enjoy maths, you should choose Mathsscaling effect across different subjects. While all
Extension 2 in order to take advantage of itssubjects are different and some will be more
enormous scaling effect. Similarly, if you enjoydifficult than others, the best approach to dealing
science, you should take Chemistry and Physics,with HSC scaling is to choose the subjects you
as they scale relatively well.are interested in, while giving consideration to the
In other words, comparing subjects in terms ofscaling effect of your choices. (For more
their scaling effect can assist you with yourinformation, read our article on HSC subject
decision as to which subjects to take for yourselection).