Biased dice

[Guynoire]

People often talk about biased roulette wheels, but wouldn't biased dice be just as likely to find? Suppose hypothetically that a casino wants to cheat its customers at craps. Knowing that most people bet the pass line, if I were going to cheat people I would alter the dice to make the one more probable, resulting in more first throw losses. A slight change in the one, say changing the probability from 1/6 to 1/5 would give the house about a 4% advantage on the pass line and make the don't pass line profitable to the player.

Does anyone have any experience finding biased dice? I think about 50 throws would be necessary to determine a bias, do casinos change dice too frequently for you to do this?

 

[bj bob]

Not very likely

For several reasons. 1) There are always an entire set of dice in play at a table, usually 5 or 6 and are continually put into a tray which is emptied in front of the shooter, making it virtually impossible for any two dice to be thrown together constantly. 2) Because of craps unique feature of the don't come any pattern displaying such patterns would be picked up by wrong way players, myself included ,and would wipe out a table very quickly.

 

[moo321]

You might find bias of a few hundredths of a percent, but probably nothing exploitable. Someone should do a scientific study, though, because I'm just estimating out of my ass. You could be on to something...

 

[ChefJJ]

I can't profess to have any knowledge on the subject, but it seems pretty next to nil (like Moo said). Dice don't have a real long shelf life on the table, and once they are retired and are sold as souveniers, they've been punched or have had a hole drilled through them...the evidence is destroyed! :flame:

The thing about craps is that if the house did knowingly alter the dice to produce more sevens, it may not be as big of a boon for them. If the seven is more apt to appear, that would also mean more come out naturals as well as quicker 7-outs. Who knows...just thinking off the top of my head

good luck

PS - great question Guy.

 

[Sonny]

People often talk about biased roulette wheels, but wouldn't biased dice be just as likely to find?

Not necessarily. Dice are pretty simple devices. They are equally balanced cubes with dots on the sides. There really isn’t much room for mechanical failure. Sure, there could easily be manufacturing inconsistencies that would directly affect their randomness, but those kinds of problems are usually closely monitored and tested by both the manufacturer and the casino. The procedures for testing the size and balance of a die are so simple that even a pit boss can do it. :grin:

A roulette wheel, on the other hand, is a very complicated machine with multiple failure points. If any one of those elements is performing sub-optimally then the whole machine is affected. Roulette wheels require regular maintenance by a professional technician, not just a guy in a cheap suit.

I think about 50 throws would be necessary to determine a bias...

But which die are you watching? The problem is that both dice look exactly alike. When they land on the other end of the table, how do you know which one you are recording the results of? You would either need to record the results of both dice together or create some sort of Bayesian/Brownian lovechild. I would guess that much more than 50 results would need to be recorded. Richard Epstein's book covers biased dice in wonderful detail.

-Sonny-

 

[Guynoire]

Thanks for your guys responses. It looks like the consensus is that finding naturally occurring biased dice for a period long enough to track them is pretty unlikely. I still wonder though if wrong way betting would protect you against a cheating house.

 

[Sonny]

I still wonder though if wrong way betting would protect you against a cheating house.

Not if the house could bias the 12. In that case the Pass bettors would lose and the Don't Pass bettors woud push. That would also increase the house edge on the Field bet as well since the 12 pays 2:1.

-Sonny-

 

[ChefJJ]

The procedures for testing the size and balance of a die are so simple that even a pit boss can do it. :grin:

So pit boss = caveman?!? :laugh: I love it!


On your point, Guy, wrong way betting would logically be the way to thwart a cheating house IF they had the stones to do it. Why? I'll ballpark it and say that only about 5% of the dollar amount of all craps ACTION is darkside, so if you were going to target somebody, it would be the majority! :devil:

If the 7 was disproportionally high on the probability scale, I'd probably go with a decent-sized Pass Line bet to take advantage of the over-inflated edge there for the comout, then a couple DC's or so. Or maybe...aww hell, caught myself dreaming there for a minute :sad:

good luck

 

[ChefJJ]

Not if the house could bias the 12. In that case the Pass bettors would lose and the Don't Pass bettors woud push. That would also increase the house edge on the Field bet as well since the 12 pays 2:1.

-Sonny-

Ahh yes...the ultimate screw job! Nobody would ever suspect the 12 :whip: It does make you wonder though.

good luck

 

[bj bob]

Not if the house could bias the 12. In that case the Pass bettors would lose and the Don't Pass bettors woud push. That would also increase the house edge on the Field bet as well since the 12 pays 2:1.

-Sonny-

You got me confused here, Sonny. If the 12 were fixed to appear more often, the the field bets would pay off more frequently since it is a field number. This may even provide an advantage to the player if this were a 2/3 payoff table since the HA would be 2.77% with "honest" dice, depending on how heavily the 12 was biased.
One interesting about the game of craps is that it depends soley upon the "balance" of the probabilities and any influence, on one side or the other can be exploited by a crafty craps player.

 

[Sonny]

You got me confused here, Sonny. If the 12 were fixed to appear more often, the the field bets would pay off more frequently since it is a field number.

Right, my bad. I got it backwards. If the 12 comes up more often then it would benefit the Field player as well as a few other players. As you said, changing the balance of the dice will influence different bets in different ways. Some will become worse while others become better. Coincidentally, that information can come in handy here in California (and possibly other Indian casinos that offer craps).

-Sonny-

 

[Guynoire]

As you said, changing the balance of the dice will influence different bets in different ways. Some will become worse while others become better. Coincidentally, that information can come in handy here in California (and possibly other Indian casinos that offer craps).

Are you talking about that annoying card craps they offer? Conditional probabilities of the cards will affect the odds but because the house edge is so high on all bets except the odds bet in craps I'm guessing you'll never see positive expected value from them. A player using doey don't and then deciding to take or lay odds based on the count might do better than just the wrong way bettor, but unless the casino offers something like 100X odds I think it will still be a losing bet.

 

[Sonny]

Are you talking about that annoying card craps they offer? Conditional probabilities of the cards will affect the odds but because the house edge is so high on all bets except the odds bet in craps I'm guessing you'll never see positive expected value from them.

I think you’d be surprised. Although the house edge is very high on most of the bets, the volatility is also very high. For example, removing just one 6 from the full shoe (312 cards) changes the house edge on the Boxcars prop bet by 2.64%. That’s not removing one card per deck, that’s one card per shoe! In many cases the effects of removal are cumulative, so removing two sixes from the full shoe will change the house edge by over 5%. Having one less 6 in a 53-card packet changes the house edge by a whopping 21.03%. The effects of removal are incredible in some cases.

Unfortunately, many of the bets very rarely become profitable. To make things worse, different casinos have very different procedures for dealing the game. Some use CSMs, others use dice and cards together, others use special cards with the two-die total on them instead of standard casino cards. There are many variations of the game and each requires a different method to get an advantage.

-Sonny-

 

[moo321]

I think you’d be surprised. Although the house edge is very high on most of the bets, the volatility is also very high. For example, removing just one 6 from the full shoe (312 cards) changes the house edge on the Boxcars prop bet by 2.64%. That’s not removing one card per deck, that’s one card per shoe! In many cases the effects of removal are cumulative, so removing two sixes from the full shoe will change the house edge by over 5%. Having one less 6 in a 53-card packet changes the house edge by a whopping 21.03%. The effects of removal are incredible in some cases.

Unfortunately, many of the bets very rarely become profitable. To make things worse, different casinos have very different procedures for dealing the game. Some use CSMs, others use dice and cards together, others use special cards with the two-die total on them instead of standard casino cards. There are many variations of the game and each requires a different method to get an advantage.

-Sonny-

Let's figure out if we can back-count the craps game!

 

[runningaces]

#1 I don't think a casino needs to cheat to win at craps, in fact I know they don't.
#2 Yes, YEs, YEs, the casino could get burned big time by fixing the dice by a player with half a brain in his head. First off let's use the fact that 7 is the number thats coming up on the dice all the time due to crooked dice. There is a bet in the middle of the table called big red, this is the 7, it pays 5 for 1 and is a one shake bet, take a step further and bet it as a 3 way 7, this pays 16 for 3 and is a 1 time shake bet, you must bet the 3 way 7 in multiples of $3. If the dice are crooked you can sit there and wait maybe 1 or 2 rolls without the 7 and then structure your bets on the 3 way 7 to where you are guaranteed a profit when the 7 eventually comes up. Example $6, $6, $6, $9, $9 and so on....hopefully you all understand this.

#3 If the number that keeps coming up is 12 due to the dice being "loaded" then a player can bet the horn, the 12 or the field, the risk of the casino cheating at dice could end up biting them n the ass if a player has a brain and figures it out.

 

[ChefJJ]

#3 If the number that keeps coming up is 12 due to the dice being "loaded" then a player can bet the horn, the 12 or the field, the risk of the casino cheating at dice could end up biting them n the ass if a player has a brain and figures it out.

Taking this example, you are damn right. As a matter of fact, there are so many players that bet ridiculously that they might do just what you said with the 12 being emphasized. Ever notice the Field and Horn bet addicts out there?!?

Why would the casino mess with a good thing?!? :grin:

good luck

 

[pogostick]

I know the pass & come ,taking full odds is the best bet in the house . I also know that the horn bet is one of the worst bets ,yet I have this thing about betting it on the come out roll , throwing the stick man $5 and going high on the 12 (2,3,11,12) and parlaying the bet 3 time if it hits. I have been at a cold table & it worked 2 times in about 30 min. I was celebrating when other players would have liked to kicked my ass. I know that dice control is almost impossible ,but I always V the 3s having the 6 &2 facing me & try to soft throw every time at one spot on the back wall as low as I can get ,so the dice will bounce back as little as possible. If you feel good about a system , then go for it. POGO

 

[runningaces]

I know that dice control is almost impossible , POGO

It's not as impossible as you think, but it takes the most consistent dice thrower to do it. I had some very good rolls from the left side of the stick but also quite a few 7 outs, it got to the point where I didnt think I was doing any better than just a random shooter, but recently I tried from the RIGHT of the stickman and I've had consistent success. Now I've probably only thrown the dice 300 times from the right side, but not once have I not hit at least one point, also I'm killing them on the come out with 7's and 11's. This means that if I can throw a 7 alot of the times on the come out by setting the dice differently than after the come out that I AM having some kind of effect on the dice. Now I'm not booking a flight to Vegas to just go and try this, but it does give me a glimmer of hope my next trip there. There are some other factors invlolved to have better success at control shooting, if you want the info you can PM me.

Aces

 

[Chapel]

it got to the point where I didnt think I was doing any better than just a random shooter

I think that is the core of the idea. If you are bad at dice control, it ends up becoming just a regular toss and you still have a low house edge.

 

[moo321]

It's not as impossible as you think, but it takes the most consistent dice thrower to do it. I had some very good rolls from the left side of the stick but also quite a few 7 outs, it got to the point where I didnt think I was doing any better than just a random shooter, but recently I tried from the RIGHT of the stickman and I've had consistent success. Now I've probably only thrown the dice 300 times from the right side, but not once have I not hit at least one point, also I'm killing them on the come out with 7's and 11's. This means that if I can throw a 7 alot of the times on the come out by setting the dice differently than after the come out that I AM having some kind of effect on the dice. Now I'm not booking a flight to Vegas to just go and try this, but it does give me a glimmer of hope my next trip there. There are some other factors invlolved to have better success at control shooting, if you want the info you can PM me.

Aces

Interesting results. Let us know if this turns into a longer term trend.