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> Two people engaging in consensual trade would be better off by the definition of trade. Not if their swap implicitly makes everyone else worse off though; an
by smallnamespace 8y ago
> Two people engaging in consensual trade would be better off by the definition of trade.
Not if their swap implicitly makes everyone else worse off though; and this is precisely the claim that judges make, that you cannot simply isolate the effects of the swap without considering the global consequences of the state of the 'game', so to speak.
- andrenth 8y agoNo one is worse off by others’ exchange, they’re the same as before.
- dctoedt 8y ago> No one is worse off by others’ exchange, they’re the same as before. Not necessarily. Second-order global effects need to be considered as well.
- andrenth 8y agoPlease be specific. What are these effects?
- dctoedt 8y agoFor example: Externalities — https://en.wikipedia.org/wiki/Externality https://en.wikipedia.org/wiki/Externality Instrumental rationality — https://en.wikipedia.org/wiki/Instrumental_and_value_rationality https://en.wikipedia.org/wiki/Instrumental_and_value_rationa... Cognitive biases of various flavors — https://en.wikipedia.org/wiki/Anchoring https://en.wikipedia.org/wiki/Anchoring
- andrenth 8y agoAgain, please be specific. You trade places with someone else. Now you're on your preferred school and so is the person you traded with. I wasn't able to trade, therefore I'm in the school I was assigned by the lottery. My situation is exactly the same whether you traded your place or not. How can it possibly be worse? And the global consequences, which seem to be the main concern here, has clearly improved, as more people are happier in their preferred schools.
- dctoedt 8y agoOK, we'll talk about your specific example and not globally. Suppose that Alice inherently belongs to some identifiable Group A — based on IQ, artistic- or athletic ability, ethnicity, whatever — but she gets randomly assigned to a school where the majority of students belong to Group B. It's the other way around for Bob, who inherently belongs to Group B but is randomly assigned to a school where the majority of students belong to Group A. Now suppose that Alice and Bob would each rather be in schools in which the majority consisted of "their own kind." And imagine that there are, say, 50,000 Alices and Bobs in the school district. In that situation, allowing Alices and Bobs to swap schools at will could easily result in self-sorting that might legitimately be disfavored by the school district, the state government, etc. For example, the school district might well legitimately want students to experience school with a cross-section of students from other groups, not just with "their own kind."
- andrenth 8y agoWell honestly this example isn’t very convincing. If some bureaucrat thinks children should go to this or that school, we should do it because...? Would you prevent Alice and Bob from experiencing schools that are perfect matches for their abilities? Shouldn’t this be their or their parents’ call?
- smallnamespace 8y agoWhy not go to the actual example from the article, which is that if you allow trading, then you will encourage strategic behavior from parents in picking schools in future rounds. People who don't engage in strategic ranking will on average be worse off than they were before. If all people engage in strategic ranking, then it essentially imposes the 'search cost' of gaming the system optimally on all participants; this search cost may be much greater than the local benefit of swaps. Also, some parents (e.g. the locals, the wealthy and connected) may be much better at doing strategic ranking then other parents, so it may inherently advantages certain groups over others. I think there is legitimate debate over whether the local benefits to the few are more important than global objectives, but denying that there are shared objectives (e.g. 'fairness' and de-escalating local competition) that sometimes demand local sacrifices is silly. I would be individually better off if I didn't have to pay taxes and not receive services, and yet we all recognize that if everyone could individually opt out of taxes, then the entire system would probably collapse. And don't tell me that I had the rational choice to pay taxes: my tax obligation was put on me because of my citizenship and birth, which I did not enter in out of my free will.
- ambicapter 8y agoThey might be worse off if the two traders optimized for tradeability in their initial choices.
- andrenth 8y agoIt seems unlikely that this was the case in this instance. You could argue about future lotteries, but it would make more sense to have a system design to avoid these situations. If you and I have each other’s first selection, then we should have been assigned them in the first place.