1. #1
    ms61853
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    Why are parlays considered bad plays for good players?

    I don't understand why parlays are considered sucker bets for good players. Average, I see, but why for good players?

    For example, let's assume a professional can expect to hit 53% of his bets in a standard 10/11 payout.

    Playing single bets, his winnings would be:

    0.53 * (10/11) - 0.47 = 0.012 expected return.

    But what if he consistently bet 3 team parlays? His return would be:

    (0.53^3) * ((21/11)^3) - 1) - (1 - 0.53^3) = 0.037 expected return

  2. #2
    Santo
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    If you're making +EV or correlated bets, they're not bad. You're quite correct.

    The one thing they are is higher variance, and that needs to be allowed for in bankroll management.

    See Ganchrow's (excellent) posts on the Kelly Criterion for more.

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  3. #3
    knicknut
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    Usually because parlays don't get true odds. In a true 10 team parlay, the payout for a 1 unit bet would be like betting 10 "if bets", so it would pay out (21/11)^10. Often it's up to 50% below that, since they capitalize on squares who want a chance to "hit it big" and don't realize what terrible odds they're receiving.

    BTW I haven't done the math but I suspect your second expected return is exactly three times your first one, just with some rounding error.

  4. #4
    ms61853
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    Quote Originally Posted by knicknut View Post
    Usually because parlays don't get true odds. In a true 10 team parlay, the payout for a 1 unit bet would be like betting 10 "if bets", so it would pay out (21/11)^10. Often it's up to 50% below that, since they capitalize on squares who want a chance to "hit it big" and don't realize what terrible odds they're receiving.

    BTW I haven't done the math but I suspect your second expected return is exactly three times your first one, just with some rounding error.
    No it's this:

    Chance of winning * Amount won when winning - chance of losing times amount lost when losing.

    I went over the math and I believe it s quite correct:

    (0.53^3) - the odds of winning the parlay



    ((21/11)^3) - 1) - the winnings win a bet is won (note the subtraction of "1" to account for the wager placed which is not winnings)


    (1 - 0.53^3) - the odds of losing the bet. This times "1" equals the expected loss from each from losing bets.

    BTW, I used a three team parly because you tend to get better odds on those. I haven't seen ant book which wouldn't give you at least a 10/11 win on each of the teams bet (5.95 winning return on the parlay), and many actually up the payout to 6-1.

  5. #5
    LT Profits
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    ms61853,

    I wrote an article on this topic a few years ago and posted it here in the last few months. Let me search for it anf bump it up.

  6. #6
    Ganchrow
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    Quote Originally Posted by Santo View Post
    If you're making +EV or correlated bets, they're not bad. You're quite correct.

    The one thing they are is higher variance, and that needs to be allowed for in bankroll management.

    See Ganchrow's (excellent) posts on the Kelly Criterion for more.
    Thanks, Santo.

    The OP might want to check out two of my earlier articles on Parlays and Correlated Parlays, both of which may serve as good introductions to parlays.

    And as always, if you have any questions, comments, concerns, or corrections, please don't hesitate to speak up.

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  7. #7
    Dark Horse
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    Read the book Win More, Lose Less. All the math about parlays, synthetic parlays, combinations of straight bets and parlays, teasers, etc. One of the best books on sports betting. (see gamblersbook.com). I'll be rereading it before football.

    The sucker bets are not parlays, which do require a high winning percentage, but teasers. (one clue is that many books advertise teasers, but you'll hardly ever hear them advertise parlays).

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  8. #8
    BrentCrude
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    These kind of parlays have been my savior!

    I have been killing the books doing this.Take hometeam moneyline favorite baseball teams but don't play the moneyline.Here is my winning formula with measely $5 bets that I play by the bunch.

    I go the home team moneyline favorite let's say at -1.5 +160 or so then I go the over all the time and it's nice when the over is 7 or 8.I do a 4 parlay taking two -1.5 +160 and take the over on both.You have a heavy hometown moneyline favorite where you only need an extra run scored by them to go from -130 to +150 or +160 and since they will win by 2 runs you figure they will go over 7,8 or 9 runs.

    The $5 4 team parlay usually pays $115 to $140.

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  9. #9
    Big Razorback
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    Ha funny you wrote that

    I just won that exact type of bet today.

    I had

    Detroit Tigers -1.5, over
    Boston Red Sox -1.5, over


    Except I had 250 on it... payed out nicely!!!!

    good luck

  10. #10
    Santo
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    Quote Originally Posted by Dark Horse View Post
    Read the book Win More, Lose Less. All the math about parlays, synthetic parlays, combinations of straight bets and parlays, teasers, etc. One of the best books on sports betting. (see gamblersbook.com). I'll be rereading it before football.

    The sucker bets are not parlays, which do require a high winning percentage, but teasers. (one clue is that many books advertise teasers, but you'll hardly ever hear them advertise parlays).
    Well not all teasers, there's basic strategy teasers and some other subsets, but Dan P's book is excellent.

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