Four short links: 19 August 2009
Survivor Bias, Algorithmic Trading, S3 Tools, DIY GSM
- Business Advice Plagued by Survivor Bias — “Burying the other evidence: [...] Doesn’t most business advice suffer from this fallacy? Harvard Business School’s famous case studies include only success stories. To paraphrase Peter, what if twenty other coffee shops had the same ideas, same product, and same dedication as Starbucks, but failed? How does that affect what we can learn from Starbucks’s success? (via Hacker News)
- A Bestiary of Algorithmic Trading Strategies — insight into the algorithms used by quant traders. Statistical arbitrageurs are a sort of squishy area, similar to arbs, but distinct from them. They find “pieces” of securities which are theoretically equivalent. For example, they may notice a drift between prices of oil companies which should revert to a mean value. This mean reversion should happen if the drift doesn’t have anything to do with actual corporate differences, like one company’s wells catching on fire. What you’re doing here is buying and selling the idea of an oil company, or in other words, a sort of oil company market spread risk. You’re assuming these two companies are statistically the same, and so they’ll revert to some kind of mean when one of the prices move. (via Hacker News)
- s3cmd — commandline tool for moving files into and out of Amazon S3.
- DIY GSM Network — wow. How to build your own GSM network. Bit by bit, the telcos are getting pressured by the hobbyists. This barbarian is looking forward to the day when the walled gardens are sacked. (via Slashdot)