Discussion in 'Trading' started by Commisso, Jan 22, 2002.

  1. dottom


    Commisso, with all due respect, if you understand expectancy, then you should also understand elementary probability theory.

    If you define the "micro view" as the result of an individual trade, and the "macro view" as the sum of all trades, then the average probability of each individual trade is the same as the average probability of all trades. The probability of all trades has to be the sum of its parts. This is high school math, guys.

    Now if you want to argue that each individual trade (what you call the "micro view") has a different probability, I will agree. The only thing we can know with statistical sampling is the average probability of each individual trade.

    But to say that each individual trade is 50/50 is to say that the average probability of all trades is 50/50, and that you believe in random walk.
    #51     Jan 24, 2002
  2. Cesko


    This discussion is, of course, interesting and very intellectual making some people feel really good about themselves but for all practical purposes it is useless.
    All you need to know about randomness and how it relates to individual trader is in the book "Fooled by Randomness" by N. N. Taleb (spec.p.69-80)

    After you read it if you realize that it all comes down to money management, risk-control, self control and flexibility you understand what trading is all about.

    I do not mean to approve or disapprove any previous comments, just make the board little more helpful.
    #52     Jan 25, 2002