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How to beat the ROULETTE?
26-Feb-2008
You are watching someone throwing a fair coin 4 times and all 4 times coin happens to come head what would be your bet for the fifth time? Are you going to bet head or tail? In other words is the likelihood of a tail increases after 4 heads in a row? Think about it before you read rest of this.
What about the fact that coin does not have any memory so everytime is same as previous one with same probability of 1/2 for head and tail. The answer may lie in binomial distribution. n! ------- [ P^k * (q)^(n-k)] ; q = 1-p = 1/2 in case of fair coin k! (n-k)! The order in this equation does not matter. So in case of fair coin prob of 5 heads in a row = (1/2)^5 while prob of 4 heads is 5 throw regardless of the order is = 5 * (1/2) ^ 5 So odds of getting one tail in 5 throws is 5 times higher than 5 heads in a row.Moral of the story is that it's prudent to bet that one out of 5 throws is tail but it's not prudent to bet that 5th one specifically is tail. We know that if the trials are independent the 5th throw could equally be head or tail.
So basically you can only do better in combinatorics not in the probability sense! 5 heads in a row has the same probability as 4 heads and one tail. But the combinatorics favors the 4 heads and one tail over 5 heads but the tail can come at anytime not necessarily the 5th time!
There is a caveat here though. We are assuming that the coin is fair. But if we don't know that for sure and see 4 heads in a row you may wonder if the coin is biased toward heads! Hum..
So before applying binomial formula make sure you can safely assume the coin is fair.
To sum up, if you are going to bet a good bet is to say I am willing to say in a 10 throws one or two are going to be tails. But you can never achieve odds in your favor if you are betting on a specific throw!
So let's get real now. You are in Bellagio checking the hot girl on the black jack table that all of a sudden you notice that the are 9 reds in a row on the roulette table across the room! What are you going to do?
Obviously you will see people gathering around that table and are betting their life on Black! What is an educated mathematician like you to do?
You are not fool anymore and you know that table has no memory and odds of next one being red is as good as the last one. On the other hand there has been 9 reds in a row already!! What the hell?
Think about it. Give me your comments!
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You must be Shahi
by Alborzi (not verified) on Wed Feb 27, 2008 10:31 AM PSTIts interesting when you talk to the Shahis they
immediately say are the people of Iran better of now or
they were before. The thing that you fail to calculate is the entropy. And thats how fart is related to Shaghigeh.
Back In College Discreat Math Instructor said similar things.
by Al Sefati (not verified) on Wed Feb 27, 2008 10:08 AM PSTback in college studying computer science, we had to take this class that was called discrete math...i tried a few trick i learned and one that my college professor instructed i ended losing all my money.
one MAJOR point you fail to see that there is minimum and maximum bet on those things.
Total luck.
by Anonymouse on Wed Feb 27, 2008 08:11 AM PSTI need to run your math equations by Haji Agha, they seem kind of kos-e sher to me! As far as roulette, it is total luck one way or another. If you see red coming 6 times and you bet on it the previous 6 times, you were lucky. If you bet the previous 6 times and won and then black comes on on the 7th time, you are still a winner.
I like roulette but it is pure luck and the payoff is good. I also recommend playing one of the 3 rows or columns to get paid 1.5 times, where red and black is only 1 times more. And don't forget to try your luck on the numbers and borders. You bet 10 or 20 $1s or more and get lucky. Play color, column and some numbers in one roll and your chances are much better. You can leave the roulette table with much more winnings and more quicker than a black jack table. Black jack can take for ever with nickel and diming.
Chance of getting lucky with the girl on the blackjack table is less than winning in the roulette. Who would let a guy get lucky on a blackjack table?!
I thought that you were
by Abarmard on Wed Feb 27, 2008 07:37 AM PSTI thought that you were going to talk about French pastry and how to control ourselves from eating one ;)
blackjack!
by David ET on Wed Feb 27, 2008 05:41 AM PSTI go and talk to the "hot girl on the black jack table" where the odds are probably more favorable ;D
Roulette
by Ben Madadi on Wed Feb 27, 2008 05:18 AM PSTYour calculations (I didn't look very carefully but what I saw quickly) are okay and what you say is reasonable. But in the lon-run the Roulette beats everybody because the roulette has 37 numbers (European style) and only 36 numbers are winners, so the roulette always (aggregate) cashes in 1/37, which mounts to a lot of money having in ming that huge sums usually go into the machine ;)
I don't condone gambling
by Jesus (not verified) on Wed Feb 27, 2008 12:13 AM PSTBeing Jesus and all, I can not condone gambling, but I got say, I love Vegas. It seems you have lost some money, and thus disenchanted. If you are trying to impress us with your stat equations, you did not. Or perhaps, you just got excited, because you are just taking stat 101, awesome! Keep learning, because you will find out that your analogy has a huge flaw in it. You can not apply the binomial equation, or its logic to the game of roulette. Actually, because there are no two random outcomes, because of 0, and 00 if I remember correctly. The correct distribution to use is Poisson, which takes into consideration discrete values above two randome variables.
Anyway, all events are independent to begin with, so I dont care if there are 9 reds in a row, I would go with my gut instinct, in my case, I will have some divine power on my side...:)