Objective, simple, unequivocal: they are great antidotes for thought. We like them best as charms against complicated issues. Inflation. Global warming. Selecting students into universities.
For university entry, we practise the blackest of black statistical arts. At the end of Year 12, every student gets an Australian Tertiary Admission Rank (ATAR), which is used for course cut-offs. Simpler students, parents and employers see it as an objective intelligence rating branded on your forehead.
So whenever ATARs fall, in specific courses or generally, there is mass panic. Teachers will be illiterate. Accountants will be innumerate. Doctors will not know a pacemaker from an iPhone.
At present, with our university system rapidly expanding, these fears are fanned by an alliance of educational elitists and enthusiasts. Apparently, without an average ATAR that would have shamed Einstein (who actually muffed his first university entrance exam) Australia’s universities will become gulags of mediocrity.
We should all take a deep breath, and some should hold it indefinitely. The Year 12 score is not what it used to be. In fact, it never was. In reality, an ATAR is not an IQ test administered by God.
There is no heavenly score for law at the University of Sydney. Actually, the ATAR is a more modest mechanism that matches the number of places supplied in a course to the demand for that course. It is useful, not definitive.
Consequently, if the number of places goes up, the ATAR goes down, and vice versa. This is called mathematics. There is no necessary correlation between a Year 12 score and a course’s difficulty, or the required quality of student in that course.
In an expanding university system, the effect is obvious. ATARs typically fall. But Year 12 scores have more issues than an inflated reputation. Realistically, they suffer from serious limitations as a total proxy for student quality. At the student end, how does a one-year ATAR take account of social disadvantage? Do kids get their A grades for talent and industry, or partly for postcodes?
Critically, how good is an ATAR at predicting university performance? Pretty good at high scores, but in the middle, in the 5Os and 60s, ATARs have the discriminating certainty of selecting life partners by throwing eggs at a map of Hungary. Yet much debate is about whether it is a national disaster if you can enter accountancy at 59 instead of 65. Do not let anyone prepare your tax return who says they can tell the difference.
Then there is the embarrassing truth of institutional selection scores. In many cases, they are about as transparent as budget estimates. A cut-off of 82 is not always 82. For a start, most institutions give bonuses. These can be for good reasons, such as attracting disadvantaged students, or they can have the desired effect of inflating cut-offs to implausible levels of market plausibility.
Then there are alternative entry schemes. Some are better, more sophisticated and more valid than the ATAR itself. Others conveniently pull herds of students in under the publicised ATAR.
Finally, there are myriad random loopholes through which low-scoring students can be dragged into a high-scoring course without their numbers ever embarrassing the authorities.
The net effect is students, parents and politicians should look at many cut-offs with the suspicion reserved for cheap Mercedes. All too often, they are marketing positions, not mathematics.
Of course, if you really are an ATAR junkie, it is not the marketing ATAR, but the median ATAR that matters. Good luck finding it.
We should be remembering it is not how students go into universities but how they leave that counts.
We should all be concerned with the quality of our universities: quality of resources, teaching, research, staff and students. But obsessing unduly about the ATAR is like judging the economy by the design quality of the $100 note.