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Can you beat Roulette using maths?

  1. Dec 21, 2009 #1
    Roulette, the house has the edge..

    Is there anyway to beat the game..either with a system using progressions..

    Or is it just a simple no..It can't be beat?

    Happy Christmas.
     
  2. jcsd
  3. Dec 21, 2009 #2

    Hurkyl

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    Simple no.

    On average, you will always lose one dollar for every nineteen dollars you bet. (Unless you take the five-number bet -- in which case your losses go up to one dollar and fifty cents on average) (These numbers based on the American roulette wheel with 38 numbers, including 0 and 00)


    Progression schemes are a shell game -- they simply shuffle around the risk until you don't notice it anymore. They work like the exact opposite of a single-number bet:
    • When you place money dollar on a single number, you will usually lose your money. But occasionally you will win big. But not big enough to make it worthwhile.
    • When you use a progression scheme, you will usually win some money. But occasionally, you will lose big. So big that it's not worthwhile.

    The progression scheme is actually more dangerous, because each time you increase your bet, you are increasing your average losings proportionally.
     
  4. Dec 21, 2009 #3

    DaveC426913

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    Of course, the trick is to quit after all the wins but before the big loss...
     
  5. Dec 21, 2009 #4
    "No one can possibly win at roulette unless he steals money from the table while the croupier isn't looking."Albert Einstein

    Read this document

    I prefer to play blackjack
     
  6. Dec 22, 2009 #5

    Mentallic

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    A few of my friends just became the legal age in Australia so we decided to try our luck at roulette. I wasn't surprised when a few of them thought they had magical predicting powers after guessing the right colour two or more times in a row - but then I was quite dissappointed to see that one of my more intelligent friends (that's close to my level in maths and even better than me at probability) was endulged in what this nutcase next to us had to say about increasing your odds.
    The guy believed since the dealer supposedly flicks the ball with the same strength each time, it should land in a smaller 1/2-1/3 fraction of the wheel much more often.

    After this guy managed to poison my friend's mind with insane ideas, I tried my turn at convincing him otherwise. Explaining how the dealer always flicks from the same position, but the wheel is always in a new position after each play since it spins in the game, and even if he does flick it at the same power, it couldn't be precise enough to land in the same spot (or close to it) after each flick, since it spins at least 20x around the board and - me believing chaos theory had a little say in this - a tiny power change in the flick will make a much larger difference in the end.

    He still believed the old dude was onto something...
     
  7. Dec 22, 2009 #6

    DaveC426913

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    Alas, another one of us rationals, lost to the siren-call of wishful-thinking.
     
  8. Dec 22, 2009 #7

    Pengwuino

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    This reminds me of an episode of "Breaking Vegas" where they had an episode about a physicist actually actually tried to beat the system. It was on craps. He actually studied the dice and trained his arm so well that he was able to in a sense, 'target' getting a 7 when he threw the dice. That isn't to say he was throwing a 7 at will, but he was able to do it with enough accuracy that the statistics moved into his favor and he was able to profit pretty nicely. I'm not sure how they stopped him or if they even could notice...
     
  9. Dec 22, 2009 #8

    Mentallic

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    I thought this "wishful thinking" could only grab a hold of the irrationals :biggrin:

    This I would only believe if the dice were to be thrown a short distance and were slow enough to stop after hitting the table very quickly. The faster the throws are made, the statistics would become random once more at a much faster rate.
    So in reality, I could imagine they would catch him if he's increasing his odds only because his throws of the dice are so small.
     
  10. Dec 22, 2009 #9
    There was an episode of some show on the Biography channel:

    In the 70s a group of astrophysics undergraduates decided to purchase a casino grade roulette table and use Newtonian physics to generate equations to calculate where the ball will land. The problem is that they needed calculators strapped onto their chests to make the calculations. In the 70s this was expensive... but also hard to detect. They increased their odds by I believe was 14%, unfortunately the calculators were faulty and they had to stop the operations, they bankrupted their accounts, and some of them dropped out of school.

    Nowadays, it would be easy to do this, but the casinos are alot more technologically upgraded to fight portable calculators..

    I guess the moral of the story is yes, roulette can be beaten by maths

    By the way, first post here. HI

    -John
     
  11. Dec 22, 2009 #10

    russ_watters

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    My B.S. detector is pegged offscale: do you have a source for that?
     
  12. Dec 22, 2009 #11

    turbo

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    No, you can't beat roulette. In a well-attended game, some people win and some people lose (over the short term), but the house always takes its cut in the form of 0 and 00 hits.
     
  13. Dec 22, 2009 #12
    http://shop.history.com/detail.php?a=72895 [Broken]
     
    Last edited by a moderator: May 4, 2017
  14. Dec 22, 2009 #13

    russ_watters

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    Amazing:
    http://en.wikipedia.org/wiki/Eudaemons
     
    Last edited by a moderator: May 4, 2017
  15. Dec 22, 2009 #14
    Its quite amazing they did that during a semester. Most physics programs are very demanding... Kudos to them
     
  16. Dec 22, 2009 #15

    Mentallic

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    How could this calculator take into account the random strength the dealer would put into spinning the ball around the table? I still don't believe it would work unless you take all variables into account, and since you have to place a bet before the dealer spins the ball, you're in no luck.
     
  17. Dec 22, 2009 #16
    You could easily take a variable range for the throw; there is a reason it only increased their odds only 44% though.
     
  18. Dec 22, 2009 #17

    russ_watters

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    ....It wasn't a calculator, it was a custom built computer and according to the wiki, it wasn't built in a semester, it took two years.

    I've only played a few times and can't remember if they close the bets before they put the ball in play (I'm thinking no). All I can think of for inputs is that they observe where the 00 is when the ball is thrown and assume that the dealer's throw speed is somewhat consistent. Perhaps they actually measure it over a period of time - record where the 00 is when the ball is thrown and compare that to where it landed. That's something you could almost do in your head. Though one of the guys who did this played a part in developing chaos theory, it must be a lot more complicated than that...

    ....still, I'm amazed that there really was a pattern in there.

    If that was the case, the casino could counter it by adding a random number generator to set the rpm of the wheel.
     
  19. Dec 22, 2009 #18

    Pengwuino

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    I believe you can still place a bet when the wheel is in motion. I think half way through or so, the people manning the wheel will call 'no more bets'.
     
  20. Dec 22, 2009 #19
    In theory it might not be possible to win in roulette, but a real roulette wheel wobbles which creates a bias. Here's part 1/4 of the show I thought of:
     
    Last edited by a moderator: Sep 25, 2014
  21. Dec 22, 2009 #20

    Hurkyl

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    Just an aside -- if 1000 different groups try to beat roulette, on average one of them will have a one-in-a-thousand winning streak.
     
  22. Dec 22, 2009 #21

    sylas

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    A while ago I heard about an amazing roulette system, which is guaranteed to cut the house edge to literally zero. I'm a mathematician myself, and at first I was skeptical. But then I looked into it, and in fact this system is foolproof. It's called "Caro's roulette system #1".

    The original version of the system is tailored to work with the American wheel, which includes a zero and a double zero. Some authorities believe this gives the house a better edge... but not when you use Caro's system!

    The Caro roulette system is an open secret within the casino industry. Although never explicitly mentioned, their advertising is carefully designed to prevent people from using it.

    There's nothing illegal about this, by the way. However, if you are at a roulette table for long enough, and you are using the Caro roulette system, the operators will eventually notice. Usually they'll just try to ignore it, but if you are there for too long, you are quite likely to be moved on. You will almost certainly be denied any of the usual benefits offered to players, like free parking or drinks. Some players are tempted to alter the strategy in the hope of receiving such incentives, but it is invariably the case that any deviation from the strict rules of the strategy will end up costing you more than the benefits from casino rewards.

    I know what you are all thinking. You're quite sure I'm wrong. I was the same, until I really looked into it for myself. I have worked out a full probabilistic analysis of how it works, but you don't actually need to know that level of detail to use the system effectively, so I'll gloss over those details. Here is the arrangement of numbers on the wheel (G: green; B: black; R: red). Start at green zero, move left to right along the top, drop down to double zero, and then right to left back again. That's once around the wheel clockwise.

    G0 B28 R9 B26 R30 B11 R7 B20 R32 B17 R5 B22 R34 B15 R3 B24 R36 B13 R1
    B2 R14 B35 R23 B4 R16 B33 R21 B6 R18 B31 R19 B8 R12 B29 R25 B10 R27 G00

    Here's the system (using Caro's own description)
    • First, never bet simply red or black. Also don’t bet odd or even. These are equally poor, consistently losing wagers.
    • Second, don’t be suckered into betting zero or double zero. This may seem like you’re betting with the house, but for technical reasons you are actually betting against the house—and you are taking the worst of it.
    • So, in order to negate the house advantage, you must stick to straight non-green number bets.
    • All odd red numbers turn out to be bad choices, based on over two trillion computer trials. Don’t bet them.
    • All even black numbers fair poorly, and cannot be bet, for much the same reason, which I won’t explain here.
    • Let’s get straight to the money-saving advice. Any bet you decide to make must cover only even-red or odd-black numbers. There are no exceptions.
    • Finally, you need to be very disciplined in excluding the number 30 and the group of consecutive numbers that begins with 11 and continues clockwise through and including 14.

    Cheers -- sylas
     
  23. Dec 23, 2009 #22
    Yee, I remember reading an account of this sometime ago. Not certain but believe it was in James Gleik's http://www.around.com/chaos.html" and best I can tell a true account.


    Another such story comes from the Univ of Nevada, Reno. I believe this happened in the 50's or 60's--some undergrad students got together one summer and watched roulette wheels around the clock under the assumption that small biases would become evident. Their efforts made them a fair chunk of change, and led the casinos to rotate the wheels by draping them and randomly rotating the wheels through the various stations.
     
    Last edited by a moderator: Apr 24, 2017
  24. Dec 23, 2009 #23
    I played blackjack for a living throughout the 1980's and worked with people connected to Farmer's and other roulette teams. There were teams that were quite successful at roulette. Farmer's group got a lot of press and published a book but they were far from being the most successful.

    The physics of it is not overly complicated. The dealer spins both the wheel and the ball, and the player is allowed to bet while the ball is spinning, sometimes quite late. The later the better for the player. A small computer is operated by buttons in the toes of the shoes and the player "clocks" the wheel by pressing a button each time 0 passes a certain point. The player does the same for the spinning ball. The computer program calculates the slowdown rate of the ball for each revolution and projects when the velocity will fall below the "terminal" velocity, at which time the ball will fall into the slots. This terminal velocity depends on several things, mainly the type of wheel. Some English-made wheels were best because they had a steeper wall. Also, many wheels were biased -- due to the wheel not being completely level or a defect due to wear.

    So a prediction is made of the time at which the ball will fall, and where on the outer circumference of the wheel this would happen, while at the same time predicting where the inner wheel will be at time of fall. The computer operator would receive a signal from the computer and pass it along to the bettor, who would then spread his bets across all numbers in the likely section of landing.

    In order to accomplish all of this the computer operator would often spend hours in the casino before the play gathering data so the computer could make allowances for wheel biases and terminal velocity of different areas of the wheel. Biased wheels were much easier to beat.

    Different wheels had other characteristics which made them easier or tougher to beat, as well as dealer characteristics. It doesn't matter how fast the dealer spins the ball initially, since it eventually slows down enough to clock before betting and always falls when spinning below a certain speed. What did matter was how fast the dealer spins the wheel, not the ball. A faster wheel is difficult to beat because there is more "bounce" when the ball hits the slots, therefore more chaos and less predictability. Other biases of wheels might be slots that are worn, or high slots that catch the ball better than low slots.
     
  25. Dec 23, 2009 #24
    30 is adjacent to 11.
     
  26. Dec 23, 2009 #25
    That's a big understatement. As soon as they see that you're using the Caro system, they'll immediately ask you to leave.
     
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