Are these really the most (and least) liveable suburbs in Melbourne?Posted: November 27, 2011
I never read those glossy magazine inserts in The Age (who does?) but on Friday I made an exception for The Melbourne Magazine because it promised to tell me “the most liveable suburb in the world’s most liveable city”.
The Age’s Our liveable city project ranks the “liveability” of 314 suburbs from top to bottom and claims to reveal “Melbourne’s best suburbs, the ones improving the most, and where you should buy your next home”.
Liveability is defined initially as “the general quality of a place that makes it pleasant or agreeable for people to reside in”. Fortunately, someone saw that was a tautology and wouldn’t be of any practical help. So liveability is subsequently defined by 13 measurable criteria.
These cover topography, traffic, crime, cultural facilities and parks, as well as proximity to a range of amenities – the CBD, beaches, public transport, schools, restaurants and shops. Scores out of five on each criterion are added to give an overall summary score for each suburb. Each suburb is subsequently ranked from 1 to 314 on an Index of Liveability.
Unsurprisingly with this sort of exercise, there was a lot of criticism from readers, with many pointing to apparent anomalies in the rankings. One said, “once I saw Footscray was rated higher than Middle Park I stopped reading”.
Disagreement is inevitable. People are different and so it’s hard to get consensus on just what does, or doesn’t, make a place liveable. That shouldn’t be surprising – an elderly couple, for example, is likely to have a very different definition of liveability to that of a young single. Throw in further differences, say in education, income or ethnicity, and it gets much more complex.
There is a much more straightforward and reliable way of establishing the relative liveability of suburbs. That simply involves measuring what people are prepared to pay to live in them i.e. property prices. It doesn’t require complex measures and weights (not that The Age bothered with the latter). In fact it sidesteps entirely the hardest and most intractable question of all – defining apriori just what liveability is.
Moreover, it provides a clear ranking and allows us to measure the size of the difference between suburbs. And it’s based on the actual decisions of hundreds of thousands of householders. Knowing that the average property value in South Yarra is three and a half times higher than in Hallam is a much more useful and valuable piece of information about the relative merits of the two suburbs than knowing one ranks 350 places ahead of the other on the Index of Liveability.
There’re distortions in the market so property values aren’t a perfect representation of the relative liveability of Melbourne’s suburbs. I would argue however that this approach involves infinitely fewer compromises than the methodology used by The Age. Of course it wouldn’t make a very interesting story when there’s the option available to the newspaper of bringing some “science” to the issue.
That’s not to say exercises like the Index of Liveability don’t have value. They can be useful to establish just why residents think one suburb is more liveable than another. Knowing why properties average $1,300,000 in South Yarra and $369,000 in Hallam would be very important information for policy-makers.
Interpreted this way, I think The Age’s attempt is actually better than many of the commenters are prepared to concede (even though I’m annoyed that very little information about the methodology is disclosed). You can argue the toss at the margin – for example, I suspect proximity to schools only matters in the case of certain institutions – but by and large the criteria are a reasonable compromise.
Even so, the project does have flaws. One is the questionable assumption that all criteria are of equal weight. This is highly unlikely even in terms of the way The Age conceived of the project. Had it sought to explain why property values differ between suburbs, the differences would’ve been very important, as the objective would’ve been to understand the relative contribution of each of the thirteen measures.
The key shortcoming, though, is simply that The Age tries to infer way too much from the data. The level of measurement just isn’t fine enough to discriminate between 314 suburbs, much less rank them cardinally.
For example, one of the compromises the researchers make is to measure proximity to various amenities from the centroid of each suburb, not from each house. Using the centroid is a common simplification made by researchers and that’s OK for measuring proximity to the CBD, but it’s problematic for measuring access to local amenities and facilities, especially with a polygon as large as a suburb. Researchers tend to limit their inferences to aggregates, not individual suburbs. They also tend to use smaller polygons – for example, the traffic zone layer for Melbourne has over 2,000 zones.
Despite its flaws, I think the Index of Liveability captures the general direction of differences across Melbourne, particularly at the extremes. Proximity to the CBD seems very important (although that’s partly because this measure “double counts” others like proximity to public transport). It’s just that it doesn’t even come close to delivering on the claims the newspaper makes on its behalf.