Discussion about cities

Are Michelle Obama’s ‘Food Deserts’ a myth?

May 25, 2012 – 8:32 am, by Alan Davies
   

What's the most incongruous thing about the world's largest ($1 billion) swimming pool? (click for more)

I’ve always felt there’s something dubious about the “food deserts” hypothesis that’s so captured Michelle Obama’s imagination. Now a story in the New York Times suggests my instinct might be close to the mark.

Food deserts are places that have good access to fast food outlets selling high-fat, high-sugar junk food, but poor access to supermarkets and grocery stores offering healthier food options. The hypothesis, based on research like this 2007 study, is that poor childhood health outcomes like obesity, most especially in poor neighbourhoods, are in part a direct result of the low density of supermarkets.

That theory’s never sounded convincing to me. While I don’t doubt there’s some accessibility effect, my feeling is there are other factors that explain much better why fast food is so attractive to poorer communities.

One is lots and lots of people like the taste of fast food. That’s in large measure because it’s laced with stuff we’ve evolved to crave. That was OK when sugar and fat were hard to get, but it’s bad for us when it’s plentiful.

Fast food is also just plain convenient – it requires no preparation, so it saves time and effort. That’s likely to be very attractive to a poor, single mother who might be working two jobs.

And although it’s not as cheap as buying the basic ingredients and cooking at home, fast food is affordable. It’s much cheaper relative to incomes (including low incomes) than in the past. And it’s extraordinarily cheap given it requires no labour input or skill from consumers.

Bear in mind too that not all lower socioeconomic households have the high level of education that alerts the middle class to the health dangers of fast food. Indeed, some might not feel they have the sort of positive future that makes it worthwhile to sacrifice a bucket of fries now for possible health benefits in the medium to longer term.

A study done in 2004 by Burdette et al lends support to my doubts. It examined the relationship between the body weight of 7,020 Cincinnati preschool children and three environmental factors – the proximity of the children’s residences to playgrounds; proximity to fast food restaurants; and the safety of the children’s neighbourhoods. The authors found:

There was no association between child overweight and proximity to playgrounds, proximity to fast food restaurants, or level of neighborhood crime. The association between child overweight and playground proximity did not differ by neighborhood crime level.

A new study published earlier this year also supports my reservations. An and Sturm examined daily servings of fruits, vegetables, juice, milk, soda, high-sugar foods, and fast food taken by 13,450 children and adolescents in California.

They compared their consumption against the density of businesses in their neighbourhood, distinguishing fast-food restaurants, convenience stores, small food stores, grocery stores, and large supermarkets within a specific distance (varying from 0.1 to 1.5 miles) from a respondent’s home or school. The authors found no robust relationship between food environment and consumption.

I don’t have access to the full article, so here’s what the New York Times reported last month about the An and Sturm study:

Dr. Sturm found no relationship between what type of food students said they ate, what they weighed, and the type of food within a mile and a half of their homes. He has also completed a national study of middle school students, with the same result — no consistent relationship between what the students ate and the type of food nearby. Living close to supermarkets or grocers did not make students thin and living close to fast food outlets did not make them fat.

So I’m inclined to the view that food deserts aren’t an important part of the explanation for child obesity in poor neighbourhoods. Even if there were abundant supermarkets and grocery stores in these areas, I doubt it would make a lot of difference.

But here’s a surprise. A story published last month in the New York Times, reporting on new research by Dr Helen Lee of the Public Policy Institute of California, suggested that the basic premise of food desert theory might be false. She finds low income areas don’t in fact have a significant shortfall in supermarkets and grocery stores. Read More »

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Will culling bottle shops cut domestic violence?

May 23, 2012 – 6:29 pm, by Alan Davies
   

Beautiful abandoned railway stations from all over the world - this one's in Manhattan (click to see more)

According to La Trobe University economist, Professor Harry Clarke, there’s a “bone-headed argument making the rounds” that reducing the number of liquor stores in a neighbourhood will reduce domestic violence.

The bone-headed argument comes from Michael Livingston, a research fellow at the Turning Point Alcohol and Drug Centre in Melbourne. According to the Sydney Morning Herald, Mr Livingston studied the density of liquor outlets in Victoria.

As you increase bottle shops in a neighbourhood you increase rates of domestic violence and rates of chronic disease. We know that they’re concentrated up to eight times more in poor neighbourhoods than rich neighbourhoods in Victoria.

Mr Livingstone acknowledges domestic violence is caused by a range of factors, but reckons reducing the number of packaged liquor outlets has got the potential to make a difference. “A lot of energy”, he says, “has gone into regulating the late-night economy, the pubs and bars, and that’s having some impact. I think packaged liquor is the next area that needs to be focused on.” Read More »

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Is strata title keeping up with higher density?

May 22, 2012 – 7:46 pm, by Alan Davies
   

1,011 owners of strata title properties were asked "To your knowledge, have any of the following defects ever been present in your strata scheme?' (multiple responses permitted)

More and more city-dwellers choose to live in apartments so they can live in more accessible locations. In the order of three and a half million Australians now live in multi unit housing.

Living at density with shared ownership of common property provides many benefits, but it also presents big challenges. The strata title system was introduced in the 1960s to address those problems but it’s getting old and creaky.

A new report prepared by the City Futures Research Centre at the University of New South Wales reveals a litany of difficulties with NSW’s strata titles system. It shows there are worrying inadequacies in the way multi-unit buildings in Sydney are managed and maintained.

The researcher was undertaken by Dr Hazel Easthope, Prof Bill Randolph and Sarah Judd. They consulted 1,550 individuals including 1,020 strata owners, 413 executive committee members, 106 strata managing agents and 11 peak body representatives.

They found a high incidence of building defects, a lack of engagement by owners in the running of their strata schemes and inadequate financial planning for repairs and maintenance in a lot of buildings. Many strata owners do not understand their responsibilities and rights and resolving differences can be a bitter and unhappy process. Read More »

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Do most cyclists run red lights?

May 21, 2012 – 10:08 pm, by Alan Davies
   

GeoLitt - someone has geocoded all the places mentioned in books written by J G Ballard (click for more)

More than half of cyclists ignore red lights according to British motorising organisation, The Institute of Advanced Motoring (IAM). The Institute conducted a survey which found 57% of respondents answered yes to the question: “As a cyclist, do you ever jump red lights?”

It’s a highly sensational number but it’s also highly dubious. There’s every chance the tabloid media in Australia will get onto it soon, so it’s worth looking at it more closely to see what it really means.

For starters, it comes from an on-line self-selecting survey, so there’s no reason to believe respondents are representative of cyclists as a whole. Those more inclined to take risks – read young males in particular – might be over-represented.

Or the survey might’ve been “gamed” by members of a group unsympathetic to cycling – say the members of an activist motoring organisation.

The most obvious flaw though is the way the data is presented by IAM. What it shows when looked at more closely is just 2.2% of respondents said they jump red lights “frequently” when cycling. Another 11.1% said they do it “sometimes”. Read More »

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Should cars be subsidised?

May 20, 2012 – 1:43 pm, by Alan Davies
   

Costs per passenger-km for cars and public transport in Sydney, 2005/6 (from Glazebrook, 2009)

It’s a truth universally acknowledged that private cars are massively subsidised. Indeed, cars are an object lesson in the consequences of under-pricing.

Because we don’t take account of the social costs of driving when we get behind the wheel, we drive too often, too far and in vehicles that are too large. Our cities sprawl, our roads are choked by congestion and public transport languishes for want of passengers.

All that’s pretty familiar stuff, yet despite the central role under-priced travel plays in shaping our cities, it’s astonishing how difficult it is to find reliable and objective data on the level of subsidy for cars.

The Bureau of Infrastructure, Transport and Regional Economics (BITRE) published figures last year showing expenditure on roads by all levels of government in 2008-09 was $15.8 billion. Revenue from charges and taxes levied on motorists (excluding GST) was $15.6 billion in the same year.

However this doesn’t take account of social costs. The topic appears to be so under-studied that the Victorian Competition and Efficiency Commission (VCEC) identified only one set of numbers in its 2006 report on traffic congestion. Those weren’t prepared by a technical expert but came from a submission made to VCEC by an advocacy group, the Public Transport Users Association (PTUA).

The PTUA says motorists cost the Australian community $42 billion annually in cash outlays and negative externalities. However they only pay $27 billion in taxes and charges, therefore requiring a net subsidy of $15 billion. Read More »

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Does car-sharing reduce emissions?

May 17, 2012 – 7:33 pm, by Alan Davies
   

Potential Reduction in emissions from car sharing under three scenarios (Source: Rand)

The Washington Post and DC.Streetsblog both report on a new study which estimates the potential savings in carbon emissions from car-sharing are relatively modest (see exhibit). The study was prepared by Rand Corporation for the US Department of Energy.

Car-sharing differs from car rental in a number of respects. With sharing, rentals are short term, fees are usually charged hourly, and cars are parked close to members’ dwellings or workplaces. It’s also much more reliant on automated systems for booking and accessing vehicles. And it’s up to members to keep cars clean.

Compared to owning, sharing reduces drivers’ emissions in three ways. First, drivers cover fewer kilometres, largely because standing costs like depreciation are incorporated in the hourly tariff. The perceived cost of driving is considerably higher and acts as a disincentive to low value trips.

Second, car-share vehicles are more fuel efficient. That’s partly because they tend to be newer, since they rack up kilometres fast and hence are turned over relatively quickly. It’s also partly because members can match the size of vehicle to the task. Owners on the other hand usually purchase a vehicle large enough for the most demanding task, notwithstanding that most of the time a smaller vehicle would be adequate.

The third reason is fewer vehicles need to be manufactured in the first place. One estimate cited by Rand is each car-share vehicle replaces between nine and thirteen privately owned vehicles. Read More »

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Should Freo go helmet-free?

May 16, 2012 – 6:35 pm, by Alan Davies
   

Subterranean London - all things underground, old and new (click to see more)

Fremantle City Council is proposing cyclists over 18 years of age have the option of riding without a helmet within the municipality for a trial period of between two and five years. The proposed trial would apply to segregated cycle paths and streets with a speed limit of 50 km/h. (H/T Michael McPhail).

The rationale for the trial is familiar. Council says the social cost of “lost” exercise deterred by the helmet law exceeds the social benefit from the head injuries that helmets avoid.

Presumably Council has done its due diligence, but the trial probably requires State Government permission – or perhaps even legislation – so I think it’s got very little chance of getting up. The politics just don’t work.

It would be a pity though, because from what I can see (e.g. here, here and here), much of the Australian evidence relied upon in this debate is either too old or too weak. The discussion would really benefit from some contemporary and objective data. Read More »

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Should public transport be subsidised?

May 15, 2012 – 7:29 pm, by Alan Davies
   

Index of subsidy per household and selected CityRail weekly tickets (including inflation). Source: IPART

Public transport travel in Australia’s capital cities gets a massive, growing financial subsidy (see exhibit). Passengers don’t pay for any of the capital costs and on average only pay for around a third of operating costs. Yet in spite of the subsidy, public transport only accounts for around 10% of all motorised trips.

The single largest group of beneficiaries are those who work in the CBD. They’re the main reason transport authorities have to provide enormous capacity to meet demand in the peaks. They don’t however tend to use public transport in the off-peak when there’s plenty of spare capacity – they prefer to drive.

A key question is why CBD workers – or any traveller who doesn’t qualify as disadvantaged – warrants such a massive subsidy.

One of the traditional justifications is equity. Yet most passengers aren’t on low incomes – indeed many are on quite good incomes. In fact most passengers aren’t even entitled to one of the many and varied concessions offered by transit authorities (not that even these necessarily indicate need – for example, in Victoria anyone aged 60 years or more is entitled to a generous Seniors concession, whether they’re working or not). Read More »

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Is congestion charging a good idea?

May 14, 2012 – 7:00 pm, by Alan Davies
   

TV interview with Jane Jacobs, circa 1969, on the planning of Toronto and Montreal

Every time Governments contemplate massive investments in urban road infrastructure, it’s instructive to bear in mind there’s a much better alternative. Instead of building something gargantuan like a road tunnel, they could instead elect to implement congestion charging across the metropolitan area.

This involves charging motorists for the use of road space. Ideally, the charge will vary with demand, rising to whatever level is necessary to keep traffic flowing at some minimum speed (which would in most cases still be well below the maximum permitted).

Congestion pricing has been introduced successfully in some cities e.g. Singapore, London, Stockholm. These implementations use simple cordon systems but the technology exists to implement far more sophisticated forms of pricing e.g. using transponder and GPS technologies.

Here are ten reasons why charging motorists to use congested roads would be a good idea – it would potentially: Read More »

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Is geography why some countries are richer than others?

May 13, 2012 – 8:58 pm, by Alan Davies
   

A brilliant, 360 degree panorama of Sydney. Click to view

I’ve pointed to the dangers of physical determinism many times. Space and geography are important variables explaining how cities work, but some disciplines have a marked tendency to over-state their importance and, more seriously, under-state the importance of more decisive economic and social variables.

My interest has to date been at the level of cities. So it’s interesting to see the authors of a new book, Why nations fail, point to the dangers of physical determinism at a global scale. However what really surprised me is Daron Acemoglu and James Robinson reckon Jared Diamond, author of the widely-hailed book, Guns, Germs and Steel, didn’t really nail it.

It seems like almost everyone I know has read Guns, Germs and Steel either wholly or in part, or is at least pretty familiar with the key hypothesis. Diamond addresses a question put to him in 1972 by Yali, a New Guinea politician. Yali asks: “Why is it that you white people developed so much cargo and brought it to New Guinea, but we black people had little cargo of our own?”

Diamond’s thesis is that relative differences in the material and technological development of continents can be attributed to different historical endowments of plant and animal species. Some places had more species that could be readily domesticated than others – this led to farming and ultimately to greater technological and material achievement relative to continents that weren’t endowed so fortunately. Read More »

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