Whenever I blog or comment on high frequency trading or the flash crash in a manner that suggests that monitoring and controls would go a long way toward solving fat finger or market manipulation issues, I get some very interesting responses. Some are useful, some ridiculous and some downright conspiracy-theory worthy. The diversity of these comments makes me wonder if we are talking about the same thing at all.
I am not against HFT, far from it; at Apama I pioneered the technology that gave traders the ability to build and customise these algorithms. Therefore I would like to define some of these ‘hot button’ terms as I see them. Although I do not own these terms I do have a personal interpretation of them.
My restriction will be ‘short but sweet’ definitions in one sentence. (I will refrain from using the restriction of the 140 character Tweet, because Forbes’ excellent Emily Lambert did this in one of her blog posts last year).
1. Flash crash: An anomalous event where the price or prices of an instrument or asset class spike or plummet violently (and, in some cases, immediately recovers).
2. High frequency trading: HFT exploits short-term pricing inefficiencies in order to profit from rapid, usually small, computer-driven trades.
3. Algorithmic trading: The process of a trade being made whereby a computer is programmed to make the buy/sell, when/where/what decisions.
4. Monitoring and surveillance: Using technology to detect problems, anomalies and potential abuse in real-time and over time, then flagging it up to the relevant market participants – enabling them to investigate.
5. Splash crash: The possibility of a flash crash in one asset class spilling over or ‘splashing’ across other asset classes (due to correlations either in algorithms or via ETFs), with a domino-like effect.
A free capital markets environment allows each individual his or her own interpretation of market conditions or events, and rarely will they all be 100% in sync. For example the widely used flash crash moniker was recently questioned in a Forbes blog by John Navin. Navin asserts that the ‘crash’ part of it is inaccurate. He has a point and perhaps “flash dip” is a more relevant term, but we are stuck with flash crash for the moment.
Ultimately it is up to each writer or blogger to define these terms in order to lend clarity. Criticism, of course, is still always welcome.