The finding by a Melbourne University study that Catholic (and other private) school students have higher lifetime earnings than public school students is not surprising. Lifetime earnings are influenced by education results which in turn are strongly influenced by socio-economic status (SES) and Catholic schools enrol proportionately more high SES students and fewer low SES students than public schools.
However, the study shows that Catholic school students still earn slightly more after accounting for differences in educational qualifications. It estimates an adjusted wage growth gap of $2 per hour in favour of Catholic school students that appears only after 15 years work experience, increases to $3 per hour after 20 years and then stops after 25 years.
It estimates the wage gap at 11% of average earnings. Assuming a 40-hour week over the 10 years, this would amount to only just over $50,000. For comparison, lifetime earnings of university graduates are $1 million, or 70%, more than those who did not complete Year 12.
The study attributes the small wage gap that mysteriously appears and then disappears to greater prospects of promotion because of assumed superior non-cognitive skills of Catholic school students. This is a highly speculative, unwarranted supposition for which no evidence is presented. If private school students have an advantage in non-cognitive skills why does it only have an effect after 15 years of work and then disappear after 25 years?
The study dismisses school-based social networks as an explanatory factor because it would be expected to benefit early in careers. However, an alternative explanation is that at entry level, the priority is more a matter of getting a desirable job whereas biases in promotion related to the person’s school are more likely appear later. The study offers no explanation for the disappearance of the wage gap.
The study suggests that Catholic schools do a better job of developing non-cognitive skills (self-discipline, resilience, persistence, self-motivated learning, etc.) than public schools. However, it ignores research by the Nobel Laureate, James Heckman, and others showing the importance influence of family background in acquiring non-cognitive skills.
Moreover, developing non-cognitive skills is not uniquely provided by Catholic schools (or other private schools). In fact, public schools appear to more successfully develop these skills.
The study ignores the substantial body of evidence that public school students outperform private school students at university when comparing students with similar entry scores. It is suggested this is because private school students have difficulty in adapting to the more unstructured learning environment of university. In other words, public school students have more of the non-cognitive skills required to succeed.
What the study has picked up is another facet of how the odds are stacked against disadvantaged students, the large majority of whom attend public schools. It shows why Australia’s school funding system should be changed to give greater priority to improving the results of disadvantaged students to enable them to better compete for higher paying jobs and positions of influence, power and status in society.
This article was originally published in The Guardian Australia.