If you run the numbers, it's a good time
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Tess Vigeland: Today we're continuing our series Econ Fun-01, about what economists do with their free time. You know, how they have fun, or try to, if only their big money brains would turn off. Commentator Justin Wolfers takes exercise to a competitive level. What's economics got to do with it? For Justin, just about everything.
JUSTIN WOLFERS: I'm not just an economist, I'm also a runner, training for the Marine Corps Marathon.
Runners World magazine recently argued that marathon running is an incredibly cheap sport. All you need is a pair of shoes, and you're off and running. But they're wrong.
You see, they were emphasizing the out-of-pocket cost, which is small. But the foundation of all economics is something called opportunity cost. It says that the true cost of something is the alternative you have to give up.
So each hour that I spend running is an hour that I don't spend hanging out, working, or sleeping. How do I choose? Following economic theory, I keep doing an activity only as long as it yields greater benefits than the alternative.
And as I spend my hours slugging out the miles, I'm forced to confront my choices. Instead of sweating it out on the trails, I could take on extra teaching and earn a few extra bucks. And so going running costs me good money.
The same logic applies to you. Each hour you spend on your hobby is an hour you don't spend working harder to get a promotion, studying for a degree, or shopping around for the cheapest groceries.
By my calculations my 16-week training program comes at an opportunity cost of several thousand dollars. A quicker runner would have a smaller opportunity cost. It's only because I'm both slow and an economist that I fret that the world's cheapest sport is actually incredibly expensive.
But to an economist, the choice is still a no-brainer. We think you should only do what you love, and pay for it by doing what you are good at.
By sticking to economics, I make time for running. Rather than spend hundreds of dollars worth of time cleaning my house each Sunday, I hire a cleaner, who does a better job, at a better price.
When a friend asks me to help them move, I write them a check to pay professional movers instead. It's just more efficient.
And while it can be hard to forgo extra income for a long run, it is even harder to justify wasting that time on Facebook. And with the time that saves, I'm pulling on my shoes to head out for another run.
VIGELAND: Justin Wolfers teaches business and public policy at The Wharton School at the University of Pennsylvania.