1. #1
    yisman
    yisman's Avatar Become A Pro!
    Join Date: 09-01-08
    Posts: 75,682
    Betpoints: 246162

    How would I calculate the odds of either of two outcomes happening?

    Say a soccer/futbol book has the odds of Team A winning at -110, the odds of Team B winning at +300, and the odds of a draw happening at +240.

    What would be the odds of betting against Team A winning? IOW, the latter two outcomes combined.

    I would guess it would be at somewhere between -110 and -130, but I'm mostly curious about how to apply this to other situations.

    cheers

  2. #2
    reno cool
    the meaning of harm
    reno cool's Avatar Become A Pro!
    Join Date: 07-02-08
    Posts: 3,567

    1/2.1= .476

    1/4=.25

    1/3.4=.294 total youd have to bet to return 100 for all3 is 102 ... 1/1.02= 98.03 ret

    the chance of the other 2 happening is .25+.294= 54.4%

    consider what you'd have to bet to return the same amount regardless which bet wins.
    29.40 at +240 returns 99.96
    25.00 at +300 returns 100

    so you would have to bet 54.40 to win 45.60 looks like -119

  3. #3
    Ganchrow
    Nolite te bastardes carborundorum.
    Ganchrow's Avatar Become A Pro!
    Join Date: 08-28-05
    Posts: 5,011
    Betpoints: 1088

    foo

    Quote Originally Posted by yisman View Post
    Say a soccer/futbol book has the odds of Team A winning at -110, the odds of Team B winning at +300, and the odds of a draw happening at +240.

    What would be the odds of betting against Team A winning? IOW, the latter two outcomes combined.
    If you're looking for the effective wagering odds of betting against A, then recalling that +300 and +240 are expressed as 4 and 3.4 in decimal odds, respectively:
    Odds(not A) = -100*(4 + 3.4)/(4*3.4 - 4 - 3.4) ≈ -119.35

    If, on the other hand, you're looking for the fair odds of betting against A then:

    Overround = 110/(110+100) + 100/(300+100) + 100/(240+100) ≈ 106.793%

    Pr(A) = 110/(110+100)/106.793% ≈ 49.049%
    Pr(not A) ≈ 1-49.049% ≈ 50.951%

    Odds(not A) ≈ -100*50.951%/(1-50.951%) ≈ -103.88

    See http://www.sportsbookreview.com/forum/handicappe...rcentages.html and http://www.sportsbookreview.com/forum/handicappe...ical-hold.html.

  4. #4
    yisman
    yisman's Avatar Become A Pro!
    Join Date: 09-01-08
    Posts: 75,682
    Betpoints: 246162

    thanks.

    I'm looking for effective wagering.

    Ganchrow, I'll use your method for something else and see if I got it right.

    Odds are +225 and +240

    Odds(not A) = -100*(3.25 + 3.4)/(3.4*3.25 - 3.4 - 3.25) ≈ x

    -100 * 6.65 / 11.05 -6.65

    -665 / 4.4 ≈ -151.14 = x


    Did I do that correctly?

  5. #5
    Ganchrow
    Nolite te bastardes carborundorum.
    Ganchrow's Avatar Become A Pro!
    Join Date: 08-28-05
    Posts: 5,011
    Betpoints: 1088

    Quote Originally Posted by yisman View Post
    thanks.

    I'm looking for effective wagering.

    Ganchrow, I'll use your method for something else and see if I got it right.

    Odds are +225 and +240

    Odds(not A) = -100*(3.25 + 3.4)/(3.4*3.25 - 3.4 - 3.25) ≈ x

    -100 * 6.65 / 11.05 -6.65

    -665 / 4.4 ≈ -151.14 = x


    Did I do that correctly?
    Yes, that is correct.

    A potentially more intuitive way of looking at this would be in terms of implied probabilities:
    Event X: +225 ⇒ Prob. = 100/(100+225) ≈ 30.769%
    Event Y: +240 ⇒ Prob. = 100/(100+240) ≈ 29.412%
    Hence:
    Prob(Not A) = Prob(X or Y) ≈ 30.769% + 29.412% ≈ 60.181%

    Prob. of 60.181% ⇒ decimal odds = 1/60.181% ≈ 1.6617

    1.6617 converted to US-style odds = -100/(1.6617-1) ≈ -151.14

  6. #6
    yisman
    yisman's Avatar Become A Pro!
    Join Date: 09-01-08
    Posts: 75,682
    Betpoints: 246162

    Seems the books are pretty precise on this (or at least Bodog is).

    England/Spain today.

    Bodog had Spain at -110, England at +330, and a draw at +210.

    I used the formula in your last post to eight decimal places. Answer was exactly -125.

Top