What's the win to society to "mitigate" an "incentive"?
The main incentive is reducing time and energy devoted to a zero sum game.
A hypothetical: imagine a sunken pirate ship is discovered. Now suppose 10 crews of divers get into a race to retrieve the pirate gold. It's useful to society to bring up the gold. It might be useful to society to have a race between 2 crews to bring up the gold, to make sure the first crew doesn't dilly dally. The gain to society is $GOLD - 2 x $DIVER_COST, or perhaps $GOLD_AFTER_LONG_DELAY - 1 x $DIVER_COST. On the other hand, having 10 crews of divers all competing for the gold is pointless - the gain to society is $GOLD - 10 x $DIVER_COST, which is 8 x $DIVER_COST less than if 2 diver crews chased the gold.
HFT is basically the same situation as the race for pirate gold - a lot of smart people in a race to create a fixed amount of alpha. We might be better off if they were creating new alpha elsewhere instead of all simultaneously chasing after the same alpha.
(That's not to say I'm advocating a ban on HFT on this ground. A certain amount of effort devoted to HFT is certainly a good thing, and I doubt the government would get things right. I just don't think the market is getting things perfect either.)
So this argument makes a lot of sense, but you see that it's not the argument that's being employed against HFT in general, right?
What I see are a lot of people arguing that the HFTs are getting an unfair edge on other traders, as if some main street stock picker was actually in competition with an HFT prop trading shop.
My sense of it is that many of the people making this arguments believe that were it not for HFT's, people would have frictionless access to a real efficient price for any instrument they wanted to buy, when in fact they'd just be dealing with a much clunkier and less reliable set of middlemen.
I know this is an uncommon argument against HFT - I've only heard Tyler Cowen pushing this argument, but it's the one I find most plausible.
As I said, a certain amount of HFT is a good thing. If I thought it was harmful, I'd quit my job as an HFT programmer and find something else [1]. I'm just pointing out that there are costs, which don't necessarily outweigh the benefits after a certain point.
[1] This was a major reason why I quit my job as a postdoc, rather than trying to become a professor. I believe college is mostly rent seeking and I don't feel it's right to participate in that.
So you left academia to become an HFT programmer because you thought academia was too unproductive in the context of larger society? That's one hell of a scathing critique of academia and, er, um, I can't help but wonder if the money might have had something to do with it?
Actually, the money wasn't a major factor. It's piling up, but I literally have no idea what to spend it on.
Here are my opinions from when I was an academic (I've only been working in HFT since March 2010, full time since May 2010):
My opinion from 347 days ago: universities have vastly more problems than that. They are huge bloated organizations structured around funneling money to employees (from both students and the government) rather than educating students. The main reason people still go is for status signaling purposes, otherwise they would have been replaced long ago.
From 406 days ago: a $10 million grant; my university will take about $5 million off the top in "overhead" (to be spent on overpaid administrators, student stress counselors, the latino student center, and maybe even education).
(This was roughly the period when I decided to leave academia.)
From 469 days ago: The job description of "professor" is certainly a strange beast: teacher/scientist. It makes about as much sense as actor/programmer...The perverse incentives this creates are massive. Universities hire scientists rather than teachers in order to get their hands on half the scientist's grants. Scientists waste their time masquerading as teachers... This is harmful both to science (I'm not doing research in class) and students...Actual teachers are squeezed out, since there is no room for them.
From 999 days ago: Another part of the problem is that there is no incentive for cost control in the university...I'm currently teaching a "Quantitative Reasoning" class right now. Basically, take Weeks 1-2 of Prob&Stat and expand it to fill a whole semester (half a semester, due to poor planning and miscommunication). Some of this is my fault, some of it not...Plus, my students are all art/history/literature majors, and just don't need it. Everyone in the room would be better off keeping their $4,000 and not sitting through my class.
As a fellow HFT programmer I sort of think of HFT as another asset class: eventually (as more divers go for the gold) the returns will be on par with alternative asset classes. This is the beauty of capital investment and the free market--if an industry produces outsized returns, then capital/resources/effort will be poured into that industry until the returns diminish.
The main incentive is reducing time and energy devoted to a zero sum game.
A hypothetical: imagine a sunken pirate ship is discovered. Now suppose 10 crews of divers get into a race to retrieve the pirate gold. It's useful to society to bring up the gold. It might be useful to society to have a race between 2 crews to bring up the gold, to make sure the first crew doesn't dilly dally. The gain to society is $GOLD - 2 x $DIVER_COST, or perhaps $GOLD_AFTER_LONG_DELAY - 1 x $DIVER_COST. On the other hand, having 10 crews of divers all competing for the gold is pointless - the gain to society is $GOLD - 10 x $DIVER_COST, which is 8 x $DIVER_COST less than if 2 diver crews chased the gold.
HFT is basically the same situation as the race for pirate gold - a lot of smart people in a race to create a fixed amount of alpha. We might be better off if they were creating new alpha elsewhere instead of all simultaneously chasing after the same alpha.
(That's not to say I'm advocating a ban on HFT on this ground. A certain amount of effort devoted to HFT is certainly a good thing, and I doubt the government would get things right. I just don't think the market is getting things perfect either.)