June 1st, 2004, 1:00 pm
If I could add one catchphrase that suprises me by its absence here, it would beincomplete information - of all formsIf you take the black-scholes model, it looks like hedging an option is a piece of cake, because you know everything you need to know. For real investors and traders, this is not that close to reality. Investors don't know the pitfalls, traders don't know that CEOs are pull a hostile takeover, don't know where the liquidity went, etc. Believe me, the daily bread of banking is not in hedging derivatives. Models are often used to gauge the impact of actions and reactions which are often fairly qualitative in nature. Such a user is not going to be very patient with your lecturing on the finer points of certain sigma-algebras. Markets are made when the incomplete information isn't too big - that's basically Akerlof'sthesis in 'the market for lemons'. Knowing which piece of the information to offer without giving away your edge is the moneymaking part of this game. Models don't fit cleanly into this viewpoint because of the high level of real uncertainty (i.e. the risk that is not quantifiable), but they still offer real power to make qualitative decisions. So, I think that trying to push people into a 'quantitative trader' box completely misses the point. We're not here to build a perpetual motion machine. Managing investments requires active engagement - you don't just come up with the golden goose and then follow the exponential growth of your wealth from your Chateau.