I’ve seen a bunch of reports from the census saying that the proportion of Australians reporting “no religion” has increased substantially, to around 22 per cent. I’d be interested to know if this is mainly a cohort effect (non-believing younger generations entering the population) or the result of people who previously reported a religious affiliation switching to reporting none. I’d be surprised if much of it was the result of people abandoning previous religious beliefs, as opposed to nominal affiliations, but I don’t think the data allows a test of this.
I just had a brilliant idea for how to motivate this effort. The first person to give a good answer gets to nominate the next topic for crowdsourcing. As a hint, the ideal way to answer the question would be to compare responses from a given age group in 2006 with the same group, now 5 years older, in 2011, adjusting, if possible for migration effects.
Update: The evidence, collected in the comments threads, suggests that cohort and conversion effects each account for about half of the shift.
The prize goes to David Barry, with honorable mentions to Aldonius and Luke Elford. I’ll give Dave first shot at proposing a new topic (in comments), but also invite suggestions from Luke and Aldonius. Meanwhile, I’m going to suggest something a bit more challenging for crowd-sourcing. If anyone would like to use the data to develop a simple model to project likely changes in stated Census affilations over the next two decades, with a specific focus on the question “When will (Census reported) Christian affilation become a minority response in Australia”, I’ll add a write up and send it as a joint post to The Conversation, the new(ish) academic-focused website.