Fooled By Randomness

While focused on investment banking there are many generally applicable concepts from Fooled by Random. The basic idea is that far more of our lives, our successes and failures, are dominated by chance than we care to admit, or are even able to perceive. Survivorship bias plays an outsized role in how society celebrates success. The hero worship around the rich and famous incorrectly ascribes the majority of their success to skill or intelligence or hard work or other traits that we claim to hold worthy; while the reality is they likely have some of those traits but no more so than the many others who did not get that pivotal first role, or whose company did not time their product market fit as fortuitously. While the societal implications of this survivor bias are interesting, especially in the age of social media and widespread feelings of inadequacy, more relevant to security is the trading strategy he proposes, wherein one seeks to make small gains during normal events while protecting yourself from going bust on unexpected events, or better yet capitalize on ‘impossible’ events to make large returns. He is highly critical of the value of historical data in predicting future performance. That leaves me wondering how to make decisions under uncertainty. Should we go back to reading entrails as in the beginning of against the gods? Are those outcomes just as good as Bayes or Dempster-Shaffer could produce? I think the key is that priors can be useful, if imperfect, while systems are operating in a common mode. You need to plan for radical switches in mode, where fundamentals no longer apply - think cheap quantum computing rendering most encryption easily breakable - but for the 90% cases prior knowledge is valuable, and therefore the rigor around adding quantitative methods to experience still holds value. 

Interestingly, the author does not read the daily news. This is something I am actually interested in, focusing my reading on longer form analysis like the Atlantic, or full length books, and skipping the Apple news headlines - I just click through the ones about dogs anyways.