On Sun, Aug 4, 2019 at 7:03 PM Jose Mario Quintana < [email protected]> wrote:
> "So I'm not seeing the problem." > > The paper, of which you are fond, implies that there might (or there might > not) be at least one mighty ghost technical trading strategy which, in a > simulation, would have convincingly beaten a given market for a period of > time in the past, and one would probably never know depending on whether > P≠NP or not. > However, even if a mighty ghost makes a sudden apparition, there is no > assurance it would be able to beat the particular market (in which it was > backtested) in real-time betting real money because, for example, a phantom > concealed unregulated trading strategy might (or might not) start operating > ruining the actual mighty ghost trades. (Once again, "Past performance is > not [necessarily] indicative of future results.") Instead of invoking > ghosts and phantoms I prefer to cite an actual trading record, such as the > one from the very smart lady I mentioned, as likely concrete evidence > against the EMH (in a specific context). That's not what it says. It does suggest that EMH would have implications about the nature of trading. But its central argument is that is the market were efficient that we could expect the market to have problem solving properties which it doesn't have. -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
