1. #1
    indio
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    Test your gambling instincts (4 question multiple choice quiz)

    Andy A shoots free throws at 75%, Bobby B shoots free throws at 70%, and they have a contest to see who makes more free throws shooting 10 free throws each. Naturally, degenerates want to gamble on it so you are asked to set lines.

    Which option is the only line where neither side would have an advantage. (Question #1)

    A. Andy -150/Bobby +130 B. Andy -170/Bobby +150 C. Andy -190/Bobby +165 D. Andy -210/Bobby +190


    Now, Bobby is stubborn because he's playing Andy even up but after getting beat a few times he wants a spot so now they decide to play where Bobby gets 1/2 a free throw (wins on all ties). The degenerates are still gambling, you now have to set a line with Andy -1/2. Which option is the only line where neither side has an advantage. (Question #2)

    Andy -1/2 vs Bobby +1/2

    A. Andy -130/Bobby +110 B. Andy +110/Bobby -130 C. Andy +100/Bobby -120 D. Andy -110/Bobby -110


    Now you're asked to put an over/under on the combined free throws made by both Andy and Bobby. You figure since one averages 7.5 per 10 and the other 7 per 10, that 14.5 would be a good line, which it is. So you offer OVER 14.5 at -105 and UNDER 14.5 AT -105. As good as this line is, one of the sides has a very slight advantage of expectation for the player.

    Which side has a slight +EV for the player (Question #3).

    A. Over 14.5 -105 B. Under 14.5 -105



    Now that some of the gamblers are stuck, they want something with a higher payoff to get even so you offer the draw as an option. Of course, there are a few who have large rolls that might want to lay against the draw. Which line offering Andy and Bobby to tie is the only one where neither side has an advantage. (Question #4)


    A. No Draw -375/ Draw +300 B. No Draw -480/Draw +400 C. No Draw -550/Draw +450 D.No Draw-600/Draw +500


    For those that can figure the math, you should get all 4 right if you don't make a mistake, for those that can't or don't want to but want to see how good their instinct is, i think 3/4 will be a good score. I'll reveal the answers when I get home around 2am EST.

  2. #2
    xdodger19
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    1 shooter 100 attempts 1 shot
    Player B
    70 times Player B makes the shot, 30 times player B misses and 22.5 times when the miss occurs player a makes it. so Player B can Expect to tie 77.5 percent of time, win 8.75 percent of time and lose 11.25 times.
    then you go 11.25/8.75 to find your even spread

    So this means the odds should be at Andy -128/Bobby +128
    after the half point Andy would be at +788

    Question 3 the answer is its a loss because the juice is -105, there is no edge either way if their is no juice.

    It should be a draw 60 percent of time

    22.5 percent of the time player A wins

    17.5 percent player B wins
    that is why the half point changes everything because player b now wins 88.75 percent of the time.
    Last edited by xdodger19; 03-28-15 at 03:25 AM.

  3. #3
    MoMoneyMoVaughn
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  4. #4
    indio
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    Here's the answers to the questions.

    Question #1. The correct answer is B.

    The chances of Andy winning outright is 50.08%, the chances of Bobby winning outright is 30.65% and the chances of a draw is 19.27%, so the true no margin money line would be Andy -163/ Bobby +163 making B. the correct answer.

    Question #2. The correct answer is D.

    when Bobby is +1/2 and wins on ties, this is about as close to a pick'em as possible. Andy is 50.08% and Bobby is 49.92% making this a virtual coin flip.

    Question #3. The correct answer is A.

    The combined score for both will be 15 or higher 51.52% of the time, making over 14.5 a true -106 and making the price of -105 a very very slight edge to the player.

    Question #4 The correct answer is B

    Since they will be expected to draw 19.27% of the time, the true odds are +413 which makes B. the only line with no player edges.

  5. #5
    statnerds
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    that's all bull pucky until we define:

    are they shooting indoors or outdoors

    clear backboard or solid white

    whom shoots first

  6. #6
    indio
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    Quote Originally Posted by statnerds View Post
    that's all bull pucky until we define:

    are they shooting indoors or outdoors

    clear backboard or solid white

    whom shoots first
    This was a math probability/odds question. So the conditions are the same as the ones that they established their make percentage. If it makes you feel better, they both have a sample size of a million free throws each.

    Who shoots first has absolutely no effect on anything.

    Judging by the content of the only 3 replies this thread got, the quality of these boards has sunk to new depths.

    If this is any indication of the types that hang in the handicapper think tank these days, I don't think threads like this are worth the time to write them. Perhaps I'll come up with something more fitting for this new generation of SBR think tankers next time, and maybe I can write it in a crayon font.

  7. #7
    LT Profits
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    Actually for Question #1, give me the underdog for the max for each option because the right answer is Andy wins 51.7% of the time and Bobby wins 48.3% for a no-vig line of Andy -107.1. You set TWO-WAY lines with no DRAW option, meaning Draws are ignored. The answer you gave is for three-way line option.

  8. #8
    LT Profits
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    Quote Originally Posted by LT Profits View Post
    Actually for Question #1, give me the underdog for the max for each option because the right answer is Andy wins 51.7% of the time and Bobby wins 48.3% for a no-vig line of Andy -107.1. You set TWO-WAY lines with no DRAW option, meaning Draws are ignored. The answer you gave is for three-way line option.
    Actually that last sentence is partly true, you set you two-way lines based on three-way computations. For two-way, draws are ignored so no-vig over 100 non-draws is simply .75/.70 = .517.

  9. #9
    BuckyOne
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    [QUOTE=indio;23792875]Here's the answers to the questions.

    Question #1. The correct answer is B.

    The chances of Andy winning outright is 50.08%, the chances of Bobby winning outright is 30.65% and the chances of a draw is 19.27%, so the true no margin money line would be Andy -163/ Bobby +163 making B. the correct answer.

    What does the math look like on Andy and Bobby winning outright. How did you get those %'s?

  10. #10
    nate686
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    Awesome quiz, thanks

  11. #11
    the_orangekat
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    A
    a
    b
    b

  12. #12
    indio
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    Quote Originally Posted by LT Profits View Post
    Actually for Question #1, give me the underdog for the max for each option because the right answer is Andy wins 51.7% of the time and Bobby wins 48.3% for a no-vig line of Andy -107.1. You set TWO-WAY lines with no DRAW option, meaning Draws are ignored. The answer you gave is for three-way line option.
    It's a two way line so obviously draws are pushes. Since Andy wins 50.08% of the time, and Bobby wins 30.65% of the time, the -163 true money line is correct (50.38/30.65). The fact that they draw 19.27% of the time is irrelevant. On question #2 when there is a spread line of 1/2, then Bobby will win on draws, and increase his win rate to 49.92%.

  13. #13
    indio
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    Quote Originally Posted by LT Profits View Post
    Actually that last sentence is partly true, you set you two-way lines based on three-way computations. For two-way, draws are ignored so no-vig over 100 non-draws is simply .75/.70 = .517.
    Your math is completely faulty. In fact, it's so bad that you might want to take a basic statistics course. To set the proper line, we must look at the probability of all 121 scenarios and their respective probabilities.

    Take a long look at your statement and reason it out, and you should begin to understand how silly your statement is.

  14. #14
    indio
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    [QUOTE=BuckyOne;23799725]
    Quote Originally Posted by indio View Post
    Here's the answers to the questions.

    Question #1. The correct answer is B.

    The chances of Andy winning outright is 50.08%, the chances of Bobby winning outright is 30.65% and the chances of a draw is 19.27%, so the true no margin money line would be Andy -163/ Bobby +163 making B. the correct answer.

    What does the math look like on Andy and Bobby winning outright. How did you get those %'s?
    All we do to get the proper numbers is to look at every scenario and figure out the chances. This is done with a binomial calculator.

    There are 121 scenarios possible when Andy and Bobby take 10 free throws each. Andy will make 10,9,8,7,6,5,4,3,2,1,or 0, and Bobby will make 10,9,8,7,6,5,4,3,2,1,or 0. This gives us 121 possibilities each with separate probabilities of occurring. For example, we can figure the chances of a draw occurring by adding together the chances of each draw result, of which there are 11. Some of the draw results have such a ridiculously low chance of happening that we can ignore them. the chances of 0-0,1-1, and 2-2, are off the charts (a 2-2 score has about a 1.8 million to one chance). The draw score lines that we add up would be 4-4, 5-5, 6-6, 7-7, 8-8, 9-9, and 10-10.
    For example, Andy has a 28.16% chance of making exactly 8 free throws, and Bobby has a 23.35% chance of making exactly 8 free throws, so obviously the chances that the final score being 8-8 would be .2816 x .2335 for a total of 6.58%. When we add up all the draw chances, we get our 19.27% chance of a draw.

    4-4 = 0.06
    5-5 = 0.60
    6-6 = 2.92
    7-7 = 6.68
    8-8 = 6.58
    9-9 = 2.27
    10-10 = 0.16
    draw = 19.27%

    And you can get the picture of how we can evaluate the 55 ways Andy can beat Bobby, and the 55 ways Bobby can beat Andy..

  15. #15
    DRB
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    Bravo on such a clever application of binomial probability to gambling.
    Obviously you have had excellent training in this area.

    Here is my follow up intuitive question :

    If you walked into a large vegas Sports Book ( MGM, Westgate, whatever ) please use your gut ( Indio in particular but
    anyone of course ) and presented one of the more straightforward of your problem set to 100 gamblers, please set the OVER/UNDER on how many would have a clue on how to proceed. I look forward to some answers tomorrow.

    Good nite and Good Luck

  16. #16
    indio
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    Quote Originally Posted by DRB View Post
    Bravo on such a clever application of binomial probability to gambling.
    Obviously you have had excellent training in this area.

    Here is my follow up intuitive question :

    If you walked into a large vegas Sports Book ( MGM, Westgate, whatever ) please use your gut ( Indio in particular but
    anyone of course ) and presented one of the more straightforward of your problem set to 100 gamblers, please set the OVER/UNDER on how many would have a clue on how to proceed. I look forward to some answers tomorrow.

    Good nite and Good Luck
    Ha-ha.

    Let's see, a large Vegas sportsbook to a random selection of 100 gamblers. I'll put the over/under at 1.5, and then, considering we're in a Vegas corporate square book, I'll lay 1/5 that anyone who knows how to proceed is instantly limited by that sportsbook, and all their future bets need "management approval".

  17. #17
    Pappas40
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    confusing??

  18. #18
    BuckyOne
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    Thanks for the math. Interesting application. I have always been interested in technical trading versus fundamentalism. Let's say you and I were going to bet a dime a contest for Andy and Bobby. We use your math to find a scientific edge. But, in sports, we need to dig deeper.

    Where did Andy and Bobby achieve their numbers (how do they shoot if the site is the Syracuse dome?)
    If Andy and Bobby get $1000 for winning - does it alter their performance?
    What if Andy just broke up with his girl friend?
    What if Bobby is hungover like a dog?

    Then again, the fundamentals can all line up but the technical things are on the other side.

    Very seldom do technical trades and fundamental traders agree on finding value, LOL. I like the math but I want to know more about Bobby and Andy before I bet on this event! Thanks for the discussion.

  19. #19
    DRB
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    Of course Indio. Not only is 1.5 the first number that came to mind, I never really gave much consideration to any other number and I do agree that the under is heavily favored. Face it - we are afflicted with the same disease

    Pappas40 , your honest answer leads me to say not to worry about the details just consider the underlying message :
    These propositional type of bets that are growing exponentially in popularity are not as straightforward as for example
    should I lay 108 or 106 on the same line ( cut to chimpanzee scratching head )
    Proceed carefully when diving in and good luck !

    DrB - out

  20. #20
    Optional
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    Quote Originally Posted by indio View Post

    All we do to get the proper numbers is to look at every scenario and figure out the chances. This is done with a binomial calculator.

    There are 121 scenarios possible when Andy and Bobby take 10 free throws each. Andy will make 10,9,8,7,6,5,4,3,2,1,or 0, and Bobby will make 10,9,8,7,6,5,4,3,2,1,or 0. This gives us 121 possibilities each with separate probabilities of occurring. For example, we can figure the chances of a draw occurring by adding together the chances of each draw result, of which there are 11. Some of the draw results have such a ridiculously low chance of happening that we can ignore them. the chances of 0-0,1-1, and 2-2, are off the charts (a 2-2 score has about a 1.8 million to one chance). The draw score lines that we add up would be 4-4, 5-5, 6-6, 7-7, 8-8, 9-9, and 10-10.
    For example, Andy has a 28.16% chance of making exactly 8 free throws, and Bobby has a 23.35% chance of making exactly 8 free throws, so obviously the chances that the final score being 8-8 would be .2816 x .2335 for a total of 6.58%. When we add up all the draw chances, we get our 19.27% chance of a draw.

    4-4 = 0.06
    5-5 = 0.60
    6-6 = 2.92
    7-7 = 6.68
    8-8 = 6.58
    9-9 = 2.27
    10-10 = 0.16
    draw = 19.27%

    And you can get the picture of how we can evaluate the 55 ways Andy can beat Bobby, and the 55 ways Bobby can beat Andy..
    You should set a new similar question now and see if this helped people.

    I'll stick up my hand and risk looking dumb and say I love the simple to understand examples but not certain I could get to the right result still.

    Maybe give people a day to PM you an answer before posting it.

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