October 30, 2016
What do criminal records tell us about Adam Smith and the Industrial Revolution?
Emily Skarbek
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I was struck when he showed the graph of deaths from whooping cough and concluded giving whooping cough vaccinations was irrational.
Because whatever your position on 'the war on terror' that is the logic behind his use of the first graph. Perhaps the post 2001 numbers are a sign of success. Freakonomics made a similar point about the relatively low number of lynchings after WWI.
Am I the only troubled by the loose use of 'irrational'? If your aim is to advance your country's economic wellbeing then supporting protectionism really is irrational, as it is counter productive. But it's a lot less clear that supporting say the Patriot Act or the Iraq invasion is irrational in the same way. It could be misguided, immoral, mistaken, or illinformed but it could also actually serve the desired purpose. The war on drugs is disastous but it's not so clear it's irrational as it does in fact reduce drug use. Just arguing, ah but the cost is too high is not good enough as it assumes a valuation of the costs involved. Irationality should be judged using the valuation of the advocate himself I suggest.
It's worth remarking that, whatever the merits of his presentation, he uses the government's definition of terrorist activities, which excludes any and all government acts of terror. This means, for example, that the federal government assault on the Branch Dravidians in their Waco compound does not count as terrorism.
His analogy of policymakers being like doctors who pick treatments out of a hat may be overly optimistic in some cases.
The doctors pick blindly, i.e., randomly (assuming they forgo the use of other senses like touch). Public support of policies, however, may sometimes be systematically biased in the exact wrong direction (for example, we may be hardwired to generally support protectionism).
Thus, randomly picking gets the right policy some of the time by pure luck. Systematically looking into the hat and purposely discarding any treatment that might actually work, however...
At Ken B:
I'm not so sure. The point that I think you are missing is WHY people desire some specific outcome when choosing some policy. For example, why do people care if drug use is reduced? The implication is that decreasing drug is socially better than the status quo of drug use, and advocating a policy to decrease drug use therefore would seem to me to be aimed at social improvement.
From this standpoint one can show that the drug war is indeed irrational because it is counterproductive to the actual desired goal: decreasing social disfunction.
Slim934: I certainly agree that the war on drugs causes vastly more harm than it prevents. I suspect that most people, if they saw that, would abandon their support. That is what happened with prohibition. But not everyone would or did back then, and have not yet. In either case it requires a measure of the good and the harm, and my point is you need to use the advocate's measures to tell if his advocacy is irrational. I don''t think Huemer does that consistently.
Great video, but I have a question.
When people talk about the irrationality of voting, how are they calculating the odds that you will flip an election? I get a much more optimistic estimate than the (I think) “1 in 10 million” odds that Huemer gives. I’m not picking on Huemer, either; I’ve seen other writers do this flippantly without explaining how they got their numbers.
If there are two other voters, and it’s a dead heat (each has a 50/50 chance of flipping the election), your odds of flipping an election are 50%. If there are 20 voters once again in a dead heat, the odds that you will be a tiebreaker are ~18%. For 200, the odds are ~6%. For 2 million, the odds are around 6 in 10,000. This falls off like 1/sqrt(N), not like 1/N. There are numerous considerations you can incorporate in this simple model, but some make them MORE favorable to your odds of being the deciding vote. (Consider that 90% of the population have probably locked in their votes, and only 10% of the election is truly in a “dead heat.”)
If you care about only the PRIVATE benefit of voting, then sure, it’s irrational. But note that the public benefit should scale like sqrt(N), where N is the number of voters. (Assume the benefits of a policy scale with the size of a population, multiply the benefit of achieving a good policy by the odds that your vote will decide that policy, and you get something that scales like sqrt(N).) Someone with a mild preference for being altruistic should be MORE willing to vote as the population increases.
Is there a more sensible model than the one I described here that’s well known to the pundits of irrational voting? If you model a deadheat election not as “Everyone has a 50/50 chance of voting either way” but rather as “everyone has an X/(1X) chance of voting either way, with X centered around 50,” do you get much smaller odds like the one Huemer gives?
@Greg S:
To make it simpler assume that there are 2n + 1 voters, and all 2n others vote. You are the one. There are some enormous number of possible youless outcomes, 2n to 0, 2n1 to 1, etc. Since there are 2n ways the vote can be 2n1 to 1, etc the numbers explode fast. You decide the election only in the n to n cases which in the grand schemes is very few. N does not have to be very large before we get to 1 in 10 million or scarcer, which is in any case just a way of saying 'so remote you it's not worth even a fraction of a second spent worrying about it.'
I share Ken B's discomfort with Huemer's use of the term "irrational." Seems to me that if one were to define "irrational" as knowingly acting against one's self interest, then the ignorance that Huemer describes voters possessing is a perfectly rational way to go about one's business as a voter/citizen. How is it acting against one's self interest to fail to become informed when acquiring information has no net positive payoff?
Did he offer a single interesting point that you didn't make first? Why doesn't he credit you?
@Ken B
Calculate a few probabilities and see for yourself. The numbers I present, and the "falls off as 1/sqrt(N)" implication, take your combinatorial argument into account. If you assume a "too close to call" election means essentially everyone has a 50/50 chance of voting either way, the possible outcomes are very strongly centered around a close tie.
I understand the intution you're using: "Combinatorial considerations make any given outcome unlikely." But I've gone a step further and computed some actual probabilities, and I'm still convinced of my position.
Okay, I think I have to withdraw my claim and admit that my model is insufficient.
From "The Empirical Frequency of a Pivotal Vote" by Mulligan and Hunter:
"Roughly one of every 30,000 elections with 100,000 votes are decided by one vote. For elections with 5,000 or 20,000 votes, the frequencies are 1/1500 or 1/6000, respectively."
The probability of swinging an election probably drops off like 1/N. Still, if the benefit of a good outcome grows like N (a reasonable assumption), the social benefit of voting scales like a constant. I still wish economists who teach that "voting is irrational, if one considers the private benefit" would add "but it's still worth doing if you consider the public benefit." We need economically literate people to be MORE willing to vote; they tend to only learn the arguments that make them LESS willing.
Behold the difference between this blog and most on the web:
"I think I have to withdraw my claim and admit that my model is insufficient." Here when someone realizes he made a mistake he says so. It would be nice if this kind of honesty were common.
I take Bryan's suggestions serious but I'm underwhelmed. Starts off with a dubious example of irrationality and then doesn't get much better.
It is mainly a pejorative to call something 'irrational'. People have reasons for what they do, and hence they must in one important sense be rational. This seems more about what is inefficient than irrational.
Moreover, it is also far from clear that people are being personally inefficient when they do not pay much attention to the inefficient political system or enjoy expressing strong but not carefully considered views.
...rather as Michael Huemer has done? ;)