Alex Tabarrok gets shot
Posted by Daniel Hall on November 12, 2007
The flu shot, that is. And so did I. And so should you. Alex explains:
People who have the flu spread the virus so getting a flu shot not only reduces the probability that I will get the flu it reduces the probability that you will get the flu. In the language of economics the flu shot creates an external benefit, a benefit to other people not captured by the person who paid the costs of getting the shot.
Hooray for public goods!
Update: Lynne Kiesling, in a very smart post about externalities, posits that the private benefits to Alex of vaccination well outweigh his costs. His decision is thus inframarginal and a public subsidy for his vaccination would be a wealth transfer but not improve behavior. I would say this illustrates a public good created by families and other tight social networks — they encourage citizens to act selflessly. I would also say that surely someone out there is on the margin about a vaccination decision, and it would make sense if we could target a subsidy at them. Off-hand I would guess that this group would include the poor and uninsured — although that might primarily be a problem of access and information — and the young, single, and socially mobile, since they are less likely to have compelling reasons to act selflessly. And, let’s face it, they are frequently lazy. I rarely got a flu shot when I was in my early 20s; I knew it was a good idea in theory, but just couldn’t be bothered.