"skynet is learning!": robot stock trades are weird, pretty, fast
Crop circles. That's an apt name for the visualizations we see of this alien world of milliseconds of bot trading. And it certainly gets at a central mystery surrounding them: if trading firms aren't sending out these orders, how are they getting into the market? On the quantitative trading forum, Nuclear Phynance, the consensus on the patterns seemed to be that they simply just emerged. They were the result of "a dynamical system that can enter oscillatory/unstable modes of behaviour," as one member put it. If so, what you see here really is just the afterscent of robot traders gliding through the green-on-black darkness of the financial system on their way from one real trade to another.
--Market Data Firm Spots Tracks of Bizarre Robot Traders, The Atlantic
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