Burns on Cramer
I read this paper, http://www.burns-stat.com/pages/Working/cramer_vs_pseudocramer.pdf, and found it to be interesting, however, the idea of judging real-world results against artificially constructed portfolios leaves me cold. The only reasonable way of judging performance is against stated goals. Goals tend to be specified in terms of returns (relative or absolute), variability (volatility, draw down and so forth) or a combination (Sharpe, Sortino...) and the only reasonable question is to what extent the goals are met. Judgment against a basket of random portfolios, however cleverly constructed, is simply not defined in relation to the efforts of the manager. (In this particular case, one might well ask what Cramer's goals are. They would seem to be to have fun and gather fame. Since it seems that he is eminently successful on both counts one is forced to acknowledge that he is doing a good job.) As for the challenge to chartists in the paper's conclusion, they too should be measured individually against their goals, not random portfolios. Why this emphasis on goals? Because this goals are what investors pay for. They may use past performance as a gage to ascertain whether the goal is obtainable, but by and large investors pay for specified goals and retain or fire managers on whether those goals are met. Other assessment alternatives matter little, even if they are 'better', unless investors agree and contract for them. This is after all a contractual relationship and results need to be evaluated in terms of expectations. jab
John Bollinger, CFA, CMT www.BollingerBands.com If you advance far enough, you arrive at the beginning.