I'm an avid, one might even say evangelical, bike commuter. It's no slower, in DC, than driving a car, and it's considerably cheaper and healthier. It's also more flexible--no more fractional hours wasted looking for parking when every lamppost and street sign offers a spot. And it's a whole lot better for the environment (please no silly pseudostatistics about the calories burned cycling to and from work; there's no way they're exceeded by the pint of fossil fuels you burned idling in DC traffic).

I also eagerly await the day when more people bicycle. Every other biker on the street gladdens my heart with the knowlege that we are creating a constituency for a more Megan-and-bicycle friendly world. Bike lanes! Bike racks in front of stores! Drivers and pedestrians who treat us as the special vehicles we are, rather than slow cars or fast walkers.

So as you can imagine, I'm pretty sympathetic to analyses which purport to show that bikes are economically great stuff. The problem is that these studies invariably seem to come out of the field of pseudoeconomics, which is like pseudoscience but with fake financial figures that scientifically prove you should do what you already wanted to do anyway. The leading lights of this field are found, of course, in the field of stadium construction analyses, where consultants with green eyeshades and team t-shirts produce, using only a toaster oven and 7,000 reams of 28 lb laser paper, reports showing that spending several hundred million dollars constructing a new stadium will ultimately generate 17 trillion dollars for the economy of Skokie, Illinois.

Though no one else approaches this level of creative artistry, the pseudoeconomists are rife throughout the policy world, especially among interest groups, and in local politics. Little wonder, then, that the infection frequently spreads into the environmental movement, as with this post from Gristmill. Along with fairly sensible claims about the health and pollution benefits of building bikeways to substitute for car trips, it does things like ignore non-monetary costs (whatever the bikeway land is currently being used for presumably has some value for someone), and flagrantly abuses trade theory in talking about the glories of local jobs.

Besides, lots of cyclists on the street make for a lively, inviting community -- the kind of place where families want to live, where business owners and retirees want to stay. And those things make a huge difference to local economies. Every retiree who stays in a neighborhood effectively creates a local job through his or her spending, as I noted in "Green-Collar Jobs."

Repeat after me: a community gets wealthier by making itself more productive. It does not get wealthier by making sure that more of what it consumes is produced locally.

Matt Yglesias and I cannot enrich the Atlantic community by giving up blogging in favor of hand crafting cunning little decorative objets out of gingham and rickrack and selling them to our officemates. Though Matt is a hell of a fine seamstress, and I myself am widely sought after for my exquisite color sense, we can produce our new line of country-inspired home collectibles only if we write less. Though it is true we would have created two jobs right here in the Watergate, not to mention a large number of ribbon-encrusted dust collectors, we would have lost two associate editor jobs. And people are willing to give us a lot more for our writing than for Matt's new line of Little House on the Prairie themed crocheted beer cozies .

Similarly, a bike path is good for the economy to the extent that it makes people more productive. It is not good for the economy because it produces local jobs maintaining the bike path, selling bicycles, or repairing the inevitable physical consequences of bicycle-car collisions.

Moreover, even if local spending were as fantastic as boosters claim, keeping a retiree in the community doesn't create any jobs; what that retiree spends would, to a rough approximateion, have been spent by whoever lived in his house. The only way to generate extra spending, and jobs, from retirees, is to build more houses to put them in.

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