Revenge of the Back of the Envelope Demography

AKA, “Follow ups no-one asked for”.

Last year I spent some idle time doing some rough work to see if ethnic and religious populations[1] were more clustered in Sydney than in Melbourne – presumably due to geographical factors. This was done by calculating Gini coefficients and Herfindahl indices on the numbers of various foreign born populations by postcode.

The answer was “plausible”.

OK, it was about a week of work, but since then I have discovered far quicker ways of doing things, and this morning the 2011 Census results were made available to plebs. Subsequently I have done the same calculations for the 2011 data.

For the three people who are interested here are the Gini Coefficients. I don’t think the Herfindahl Indices add much, but they are available if you really want them, as well as comparative Lorenz curve graphs. I’ve included the 2006 results for comparison.

2011 Melbourne Sydney Difference
Assemblies of God 68.24 66.35 -1.89
Atheism 45.39 42.89 -2.50
Buddhism 63.97 63.81 -0.16
Hinduism 63.67 72.39 8.71
India 64.88 72.00 7.13
Islam 73.96 76.63 2.67
Judaism 87.22 83.21 -4.01
Korea 69.62 72.52 2.90
Philippines 69.67 67.09 -2.58
Samoa 83.55 84.36 0.81
Everyone 42.85 39.91 -2.94
2006 Melbourne Sydney Difference
Assemblies of God 60.43 59.52 -0.91
Atheism 42.88 44.99 2.12
Buddhism 64.79 65.59 0.80
Hinduism 61.71 70.97 9.26
India 60.97 68.86 7.89
Islam 73.21 75.82 2.61
Judaism 87.54 83.64 -3.89
Korea 70.65 72.46 1.81
Philippines 67.91 68.80 0.89
Samoa 82.30 83.02 0.72
Everyone 42.88 39.44 -3.44

Green has a sign that supports the hypothesis that there is greater clustering in Sydney. I’ve arbitrarily denoted differences of more than 2.00 as important and coloured them bright green. “Everyone” is an indication of the the inequal distribution of all residents accross postcodes in the city. This indicates that even if there were no difference in clustering tendency, you’d expect to see higher Gini numbers for Melbourne.

Like last time, the ethnic group that prompted the investigation (Indian Australians) has the most remarkable divergence.

Atheism has swapped places. There were minuscule numbers in 2006, so I expect any change has a lot to do with the rise of Movement Atheism, and not much should be read into things.

Filipinos still do not show any non-clustering nature relative to other groups, so that’s still not a good hypothesis to explain the lack of Pinoy restaurants.

Samoans seem very clustered, but I think this is a relic of low numbers.

The Jewish population seems more clustered in Melbourne. Are there more Orthodox in the South whom need to be in walking distance of the synagogue?

All in all, the major finding is how much the differences between ethnicities is larger than the difference between cities. In almost every case, if you wanted to see how clustered a group in Sydney was, you’d get a very accurate estimate by looking at Melbourne. These cities are really staggeringly alike, despite our constant efforts to find differences between them. There are no two cities this size in the world that are so similar. I doubt this will discourage the eternal narcissism of small differences though.

[fn1] And presumably other groupings of like mindedness. Unfortunately the ABS does not have a “hipster” box in the census, so I was restricted to recorded characteristics.

About Richard Tsukamasa Green

Richard Tsukamasa Green is an economist. Public employment means he can't post on policy much anymore. Also found at @RHTGreen on twitter.
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Paul Frijters
Paul Frijters
9 years ago

yes, the city-similarity is remarkable. You’d intuitively think because of the similarity of the sub-populations rather than the cities (i.e. mainly a function of how much different ethnicities stick together).
I would expect these concentration indices to correlate highly with inter-marriage rates, which one should be able to calculate from the census.

john r walker
9 years ago

Are historical figures available for clustering? are there figures for say 1960, 1970 and 1980 ..?

9 years ago

I’m not sure that putting hipster on the census is needed. I find it pretty easy to avoid them by not going to places with single origin / fair trade coffee or milk crates for seats.

9 years ago

And keeping an eye out for men with no socks; see my tumblr below for assistance.

Avi Waksberg
Avi Waksberg
9 years ago

Interesting stuff Richard, thanks. There are two points that occur to me. First is that the 2006 data for atheist and no-religion was a bit weird because there was a movement to get ‘Jedi’ recognised as a religion in the 2006 census. Consequently, it is better to compare 2001 to 2011, at least regarding atheist and no-religion responses. Second is that Sydney is far hillier. I may be wrong, but I got the impression that suburbs are more inter-connected in Melbourne than Sydney.