Black Monday October 1987 > the DJIA fell 508 points and roughly 600 million shares were traded, both > records.
> markets, left to their own devices, can and will break down into panic and > chaos. Donna Y [email protected] > On Aug 6, 2019, at 6:11 PM, Jose Mario Quintana > <[email protected]> wrote: > > "That's not what it says." > > Really? Be that as it may, meanwhile you have not shown a single instance > of a technical strategy, of the kind entertained in that paper, able to > beat the market with a statistically significant level according to a > backtest, let alone one which can do so in real-time betting real money. > Have you? > > "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." > > You are not trying to imply, based on the claims of that paper, that the > market is inefficient. Are you? What the paper says is, > > "To be clear, we are also not trying to determine if P = NP or, for that > matter, whether markets are efficient." > > > > > > > > > > > > > > On Mon, Aug 5, 2019 at 9:23 AM Raul Miller <[email protected]> wrote: > >> 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 >> > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
