[grandinj]

"latency arbitrage" ?

The euphemism HF traders use to help themselves sleep at night.

[kasey_junk]

Thats one way to describe it. Another way to describe it is "hey prices at 2 different venues get out of whack some times, when that happens there is an opportunity to make money by bringing them back into alignment".

We don't assume other kinds of middle-men require sleep aids when they do this kind of behavior (and in fact we usually encourage it), so I don't know why HFT folks would need them either.

[grandinj]

And confidence tricksters perform trust arbitrage.

This is all just ways of saying HFT is exploiting a loop-hole in a system to make money for themselves.

They could all be eliminated overnight and the free-market system would not notice their absence at all.

They don't provide a service to anyone besides themselves, they don't provide liquidity, they are nothing except parasites.

[tptacek]

This is a little like saying the CAP theorem is a euphemism that distributed systems designers use to help themselves sleep at night.