Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Win Streak Probability

Options
  • 04-04-2017 3:21pm
    #1
    Registered Users Posts: 501 ✭✭✭


    Anybody know of an online calculator that will calculate the probability of a win streak of X games from a series of Y bets or can go through the method to calculate it? Thanks.

    E.G) If I place 500 bets at odds of 1.25 with a strike rate of 80% what is the probability that I will win 20 bets in a row?


Comments

  • Registered Users Posts: 2,338 ✭✭✭Bit cynical


    I don't know of an online calculator but I think you should be able to do it in a spreadsheet. I would appreciate if someone could point out possible flaws in my reasoning.

    The formula would be

    =1-(1-Probability^StreakLength)^(Bets - StreakLength+1)

    Probability: the probability of winning any one bet (e.g. 0.8 for 80%)
    StreakLength: how many winning bets count for a streak (e.g. 20)
    Bets: The total number of bets (e.g. 500).

    Reasoning:

    Probability of winning one streak is Probability^Streak Length.

    Probability of losing a winning streak is 1 - Probability^Streak Length.

    We get Bets - StreakLength + 1 chances of getting a a winning streak.

    Probability of failing to get a winning streak in all our chances is
    (1 - Probability^Streak Length)^(Bets - StreakLength + 1)

    and therefore the chances of getting at least one winning streak is
    1-(1 - Probability^Streak Length)^(Bets - StreakLength + 1)


Advertisement