The law-enforcement/courts system has significantly better first-time odds than Russian Roulette. For most crimes, the odds that I will be arrested and convicted and sentenced to significant jail time for a first crime are significantly lower than one in six.
"But Dave," someone will now patiently explain to me, "that doesn't matter. An N% chance of death is always going to be significantly worse than an N% chance of a paintball in the head, no matter how low N%. It's scale-invariant!"
Except the decision to ignore the psychological effects of scale is precisely what I'm skeptical about here. Sure, if I make prisons bad enough (supposing I can do so), then everyone rational does an EV calculation and concludes that even a miniscule chance of going to prison is more disutility than the opportunity cost of foregoing a crime.
But I don't think that's what most people reliably do faced with small probabilities of large disutilities. Some people, faced with that situation, look at the magnitude of the disutility and ignore the probability ("Sure it's unlikely, but if it happened it would be really awful, so let's not take the risk!"). Some people look at the magnitude of the probability and ignore the disutility ("Sure, it would be awful, but it's not going to happen, so who cares?").
Very few look at the EV.
That said, if we restrict our domain of discourse to potential criminals who do perform EV calculations (which I think is a silly thing to do in the real world, but leaving that aside for now), then I agree that doubling the expected disutility-of-punishment (e.g., making prisons twice as unpleasant) halves their chance of performing the crime.
Of course, so does doubling the expected chance of being punished in the first place .
That is, if I start out with a P1 confidence that I will be arrested and convicted for commiting a crime, a P2 confidence that if convicted I will receive significant prison time, and a >.99 confidence that the disutility of significant prison time is D1, and you want to double my expected disutility of commiting that crime, you can double P1, or P2, or D1, or mix-and-match.
So a system primarily interested in maximizing deterrent effect among rational EV calculators asks which of those strategies gets the largest increase in expected disutility for a given cost.
It's not at all clear to me that in the U.S. today, doubling D1 is the most cost-effective way to do that if I consider decreasing the QALYs of prison inmates to be a cost. So if someone insists on doubling D1, I infer that either...:
...(a) they value the QALYs of prison inmates less than I do, or
...(b) they have some reason to believe that doubling D1 is the most cost-effective way of buying deterrence, or
...(c) they aren't exclusively interested in deterrence, or
...(d) something else I haven't thought of.
In practice I usually assume some combination of (a) and (c), but I considered (b) potentially interesting enough to be worth exploring the question. At this point, though, my confidence that I can explore (b) in this conversation in an interesting way is low.
Some people look at the magnitude of the probability and ignore the disutility ("Sure, it would be awful, but it's not going to happen, so who cares?").
It seems rather difficult to actually affect those people, though. The difference between P1=.04 and P1=.08 would have dramatic effects on an EV-calculator, but very little effect on the sort of person who judges probabilities by 'feel'.
...That is, if I start out with a P1 confidence that I will be arrested and convicted for commiting a crime, a P2 confidence that if convicted I will receive sig
The next discussion thread is here.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 85. The previous thread has long passed 500 comments. Comment in the 15th thread until you read chapter 85.
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