See also "Man vs. Machine on Wall Street: How Computers Beat the Market (and should they be banned?)", above.
Oops, here's the paper:
Relativistic Statistical Arbitrage
From Kevin Drum at Mother Jones:
Via Tyler Cowen,
A. D. Wissner-Gross and C. E. Freer investigate where you should open a high-frequency trading facility given that light-speed propagation delays are a key factor in arbitraging trades between two exchanges. After much fiddling with partial differential equations, they come up with this map, which shows "Optimal intermediate trading node locations (small circles) for all pairs of 52 major securities exchanges (large circles)....from 2008 data reported by the World Federation of Exchanges." I call dibs on the location just north of Greenland.