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For many years during my undergraduate degree I was living on a scholarship alone and so learned to be a very frugal person. As computers and mobile phones got cheaper, I would always take advantage of that to get cheaper rather than better models when upgrading. Last year for instance I bought a basic smartphone for $100 and a netbook for $250. This year on the sage advice of Luke Muehlhauser I changed my approach and splurged on a MacBook and higher end Android phone. Having experienced both I realised that buying the cheap electronics was a false economy and that if I had thought about the decision properly I would have worked that out much earlier.

The reason is simple.

A high quality laptop cost me $1100 while a comparable low quality one would have cost me $500. I use my laptop an average of about 2 hours a day, and expect it to last around two years. Over its lifetime then I should expect to use it about 1400 hours. A high end laptop then costs $0.42 an hour over a low end one. I estimate that the MacBook’s design and reliability boost my productivity by at least 10%. Do I value a 10% productivity boost at $0.42 an hour? Given my wages and the importance I place on getting things done – definitely. And then there is the pleasure and serenity I get from using a well designed product on top of that.

Likewise, a good phone cost $200 more and I use my phone about half an hour a day and also expect it to last for two years so it comes to about 55c extra each hour of use. While I don’t use the phone as much, it is particularly valuable to be able to do what you need to do on your mobile quickly, for example when you are trying to find an event, some piece of information or a person you a meeting. The faster processor and better software on the expensive phone allow me to perform most tasks almost twice as quickly as on the cheap phone. This is certainly worth the cost.

My instinct without doing the numbers was that ‘to be frugal is a virtue’, but in order to save my money I was inadvertently a spendthrift with my time. In future I will divide the price of durable items like laptops into hourly costs as I have done above in order to make it easier to work out the best decision.

I recently spent some time with my brother who regaled me, as he often does, with stories of diseases I had never heard of and accidents I had never worried about. Not being too keen on death I set myself to researching tire explosions and Lyme’s disease. But I soon remembered that just because I’m hearing about or scared by something doesn’t mean it’s a significant cause of death or injury. If I don’t work from some actual numbers I will probably waste my time avoiding salient but rare causes of death. So if I really want to increase my life expectancy, what are causes of death that I should actually worry about, and what can I do about them?

Fortunately death is something we keep very good data on, and the Australian Bureau of Statistics publishes the figures broken down by location, age and gender so I can get a good idea of the risks for someone in my approximate circumstance. I encourage you to do the same using data from your own statistics bureau. Here is the rate of death per 100,000 people between 2007 and 2010 for men aged 25-35 living in Canberra:

Cause of death
Intentional self-harm (X60-X84)(g) – 18.9
Accidental poisoning by and exposure to noxious substances (X40-X49) – 10
Motorcycle rider injured in transport accident (V20-V29) – 8.9
Other forms of heart disease (I30-I52) – 5.6
Assault (X85-Y09) – 4.4
Car occupant injured in transport accident (V40-V49) – 4.4

Starting from the bottom, death in a car accident is a notable risk. No surprise there and as I usually ride a bike I’m probably at even greater risk than that figure suggests. I should travel carefully on roads and invest in lights, helmets and so on.

A few people were also killed in assaults. I don’t tend to hang around violent people so that’s probably not such a significant risk for me.

Heart disease also killed a number, which surprised me for such a young age group. My guess is these are unexpected heart attacks due to inherited heart problems. Probably not a lot to be done about that, and there is no history of early-onset heart problems in my family.

Motorbike accidents killed a huge number given how few people ride motorbikes. I’m not a motorbike rider and given this figure I don’t think I’ll take it up!

Second most significant is “accidental poisoning by and exposure to noxious substances,” which I wouldn’t have suspected. Unfortunately I couldn’t get more detailed information describing the kind of poisonings but I would guess the main ones are drug overdose and food poisoning. I will do some further research on this later using a different dataset from the Bureau of Statistics.

However the top risk by far is that I will kill myself. Though I have never had depression or been suicidal there is a history of depression and suicide in my family, so that figure probably reflects a real risk for me. How can I make sure I don’t go and kill myself? Maintain strong connections to friends and family, get help and treatment if I start feeling depressed or suicidal, join religious or cultural groups that oppose suicide, and avoid having guns, knives and poisons around the house. [1] While none of these is hard per se, the high frequency of young male suicide suggest that not everyone in my position manages to do them. Given the self-reinforcing nature of unhappiness, I should probably organise for myself and others to intervene early if I feel myself spiralling into depression.

This excellent piece of journalism outlines the importance of social supports and resilience for achieving a lot in life over the long run. If the anecdotes from that study are representative it is actually very common for smart and successful people to fly off the rails due to traumatic experiences in their lives.

Ultimately though the figures show that my risk of dying between 25 and 35 is under 1%. This is 1% too high, but it is still a pretty low risk. To find the low hanging fruit for increasing my life expectancy, I should look beyond causes of immediate death and think about my long term health. To do so I’ll take a look at what causes of death at any age result in the largest loss of potential years of life for men in Canberra in a future post.

I’m going to do a back-of-the-envelope calculation on ‘local food’ and then later ‘fair trade’ to explain why I don’t think they are worth putting much effort into. I hope it will inspire you to do the same for whatever approaches you currently use to make the world a better place.

As you probably know, local food or locovorism is where people aspire to buy food made near to where they live. On a recent trip to the States I was astonished at the size of the local food movement. Everywhere I went people would beam with pride about how nearby their food was produced. There are several proposed benefits of local food [1] but probably the most common one is wanting to reduce the environmental damage caused by food transport, so called ‘food miles’. For this to be the best thing for someone to dedicate their attention to a few things need to be true:

  • environmental degradation and climate change would need to be valuable things to direct attention to on the margin;
  • reducing your personal environmental footprint would need to be an effective thing to do about those problems;
  • buying food produced near you would need to be a cost-effective or effort-effective way to achieve that.

Let’s assume for the moment that environmental degradation were the most important problem to work on. Reducing the effect of your personal consumption would be only one way to direct your effort. Others would include working to change environmental regulations, convincing others to do more themselves, expanding humanity’s ability to adapt to environmental degradation (for instance through poverty alleviation, migration or geoengineering) or assisting researchers developing green technology. Intuitively I expect all of those to pack a bigger punch per hour than trying to change your own consumption habits. But let’s say my instinct is wrong about that.

If you wanted to reduce the environmental impact of your own consumption, would buying food produced nearby be an effective approach? Let’s get some indication of the good you could hope to do:

Desrochers and Shimizu cite a comprehensive study done by the United Kingdom’s Department of Environment, Food and Rural Affairs (DEFRA) which reported that 82 percent of food miles were generated within the U.K. Consumer shopping trips accounted for 48 percent and trucking for 31 percent of British food miles. Air freight amounted to less than 1 percent of food miles. In total, food transportation accounted for only 1.8 percent of Britain’s carbon dioxide emissions.

In the United States, a 2007 analysis found that transporting food from producers to retailers accounted for only 4 percent of greenhouse emissions related to food. According to a 2000 study, agriculture was responsible for 7.7 percent of total U.S. greenhouse gas emissions. In that study, food transport accounted for 14 percent of the greenhouse gas emissions associated with agriculture, which means that food transport is responsible for about 1 percent of total U.S. greenhouse gas emissions.

So if we assume that buying local food eliminated all emissions from food transport you could hope to cut 1-2% of your total greenhouse gas emissions. Then there are some offsetting effects. A strong preference among consumers for local food would tend to drive agriculture towards places where it is otherwise less efficient, requiring more machinery, labour or land to produce the same food. This would also be bad for the environment. On top of this, as indicated in the quote above, retail-to-home transport has about the same impact as farm-to-retail transport. If someone drives further to the farmers’ market to buy local, they could end up producing more food miles overall. How significant these offsetting effects are will vary depending on the person and the food they are buying, but they suggest that 2 per cent is a generous upper bound.

What would be the rough value of a 2 per cent reduction in your emissions? Let’s say you are a big polluter and produce 20 tonnes of CO2 equivalent each year. Let’s also take a high value of emissions reductions of $100 per tonne. This is several times the current marginal cost of reducing emissions and is probably more than enough to get us climate stabilisation at 450 CO2e, but let’s use it anyway. A 2% reduction in your emissions would then be worth $40 of good to the world (20 tonnes * $100 * 2%). This seems small to me for a year’s work buying local food, and that is the best case scenario. Insulating your home, not eating livestock or holidaying by plane, or buying up and ‘retiring’ carbon credits in carbon markets are likely to offer much more bang for buck.

Could eating local still be worthwhile? Sure. If you would eat food produced nearby for selfish rather than altruistic reasons, or are tossing up between a local and foreign item it’s little or no difference to you to choose the local one, go ahead. But if your goal is to effectively convert your time and money into good outcomes for the world it would be very surprising if ‘eating local’ were something worth making a fuss about.

[1] Other reasons I’ve heard offered are ‘I enjoy having a relationship with the farmer/land or helping small growers’ or ‘I like knowing how the animals/land are treated’. Insofar as you are eating local food because you enjoy it more you can disregard this post. As for being more informed about the effects of the farming techniques employed, or wanting to support small scale farming over big the same considerations apply. Does this really offer a high return on your effort? My other question would be: should you really have to eat locally to know how your food is produced? It seems like a less elegant solution than certification labels like ‘organic’ or ‘free range’.

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Robert WiblinHi! I am a young Australian man ostensibly interested in the truth and maximising the total number of preferences that are ever satisfied, weighted by their intensity. I also enjoy reading and writing about the topics listed above. If you share my interests, friend me on , , or or subscribe to my RSS feed .

All opinions expressed here are at most mine alone, and have nothing to do with any past, present, future or far future employers.

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