Please don’t misunderstand me, I am not saying that these schools are not good at teaching, but it is not easy to definitively demonstrate that they are.  Schools tend to claim to be good at teaching when they get good VCE scores and expensive schools usually have good VCE scores.

My question is whether the good VCE scores are attributable to the quality of the teaching the students receive or something else.

What could the something else be?  What if the school fees were a genetic screening device?  If this was the case then the fees themselves would be a contributor to the high VCE scores.  Sound fanciful?  Hear me out.

My proposition is as follows:

  1. There is a strong correlation between IQ and income. Please see the diagram above which comes from the USA – one of the few places where they collect such data.  As you can see, the higher the income, the higher the IQ, with quite a strong relationship.  This is not to say that at the individual level people with low income will have low IQs, but if you take larger numbers of people into account the trend can be seen.  There is also a personality effect on income (Roberts et al, 2007).  People who are highly conscientious and emotionally stable have higher incomes.
  2. Parents who can afford pay high fees are therefore likely to have high IQs and personalities suited to job performance.
  3. IQ is highly genetically determined – inherited. Some people put the effect size as high as 80%, others as low as 50%, so we all agree that genes have a big input.  Personality is also heavily genetically determined, with similar or perhaps wider variability in opinion about how much so.  Personally, I believe from considering a range of recent literature that around two thirds of these characteristics are genetically determined.
  4. Therefore there is a high likelihood that the children of parents who can afford to pay high fees will have high IQs and personalities suited to job performance.
  5. These are also predictors of academic performance(Komarraju et al, 2009)
  6. So expensive schools start out with a big advantage in terms of marks for VCE as they are teaching a genetically screened population.
  7. They often have merit based scholarship programmes which increase this effect of prescreening.

The psychologist Steven Pinker speaks often on a related topic.  He coined the phrase “nurture myth” to describe the pressure parents put themselves under to help their children to be smarter, have more well balanced personalities, to be healthier and so forth.  He points to research which shows that when you measure the IQs and personalities of identical twins who grow up in the same family versus those who grow up separately the correlation is the same.  This is whether they grew up cheek by jowl or have never met their parents or siblings.  Where is the nurture in that?  He says, more or less, ‘Don’t beat yourselves up parents, the hand of cards has already been dealt’.

He also says that all the studies which show that parents who read to their children cause their children to be smarter are entirely useless and prove nothing until they control for genes, which none of them do.  Otherwise, all you are proving may be that those who are smarter and interested in books are likely to have kids who are smarter and interested in books for purely genetic reasons.

So, I think the same thing may well go for expensive schools.  I understand that many parents send their children to expensive schools for a range of reasons other than teaching quality, but how good are they at teaching?  Who knows until we control for genetic background?

Andrew Marty
Managing Director

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Komarraju, M., Karau, S. J., & Schmeck, R. R. (2009). Role of the Big Five personality traits in predicting college students’ academic motivation and achievement. Learning and Individual Differences, 19, 47−52.

Roberts, B. W., Kuncel, N. R., Shiner, R., Caspi, A., & Goldberg, L. R. (2007). The power of personality: The comparative validity of personality traits, socioeconomic status, and cognitive ability for predicting important life outcomes. Perspectives on Psychological Science2(4), 313-345.

Andrew Marty