Ask the Slot Expert: Are bubble craps machines fair?

Question: I was curious if you have considered mailing your VHS copy of Jimmy "The Scot" Jordan’s Video Poker Tape to Redlettermedia.com. They have already reviewed his tape on slot machine and it was great! I think another one of his tapes would be comedic gold!

Answer: I had never heard of this site. It's kind of like Drunk History meets Mystery Science Theater 3000. Four wannabe MSTies consume a few adult beverages and review videos that their fans have sent to them.

One of the videos they reviewed was our friend Jimmy "The Scot" Jordan's Top Slots - Spotting the Best. They discuss the video in Best of the Worst: Wheel of the Worst #16. The video is almost an hour long and they don't provide an index into the video. They start ripping apart Top Slots about 24 minutes in.

I don't think they're gamblers because they didn't criticize the information given on the tape. They only criticized the minimal production values of the tape — which I'm not sure if it's self-referentially hilarious given the minimal production values of their video.

In any case, I don't see any value in sending them more Jimmy The Scot material. Been there, done that.

On the other hand, I can see Frank Scoblete, John Grochowski and myself playing OK, Stop! with clips from Jimmy's tapes.

Question: A member of Craps Forum posted a situation he had observed where a bubble craps machine automatically rerolled when it could not read a result. Another member, who has contended in other threads that the machines are rigged to increase the house advantage, asked if the observed machine rerolls only in circumstances where the perceived result would favor the players, or if it also rerolls in house-favorable situations as well. Do bubble craps machines fall under the "malfunction voids play" umbrella, and by extension, if the player has any recourse in such a situation?

Answer: I know of two manufacturers of electronic craps games — not video craps machines, but machines that agitate two physical dice and then read the result — Shoot to Win from Aruze Gaming and Organic Craps from Interblock Gaming. These machines fall into the broad category of Electronic Gaming Devices (EGDs), so malfunctions will void all pays and plays.

The Interblock machine has to be one of the most annoying machines on the casino floor. The lady host imploring players to "C'mon, press a button!" cuts through all the slot machine noises and I can frequently hear her many aisles away.

Conspiracy theories thrive in gambling, and I see that these craps machines aren't immune to participating in them. Nevada's regulations prohibit the behavior you described. Before I discuss them, let me try to find an analogous situation with other EGDs.

The closest thing on the slot floor today would be a reel-spinning slot machine. Today's machines sometimes have reel tilts, when the position in which a reel stops doesn't match the position chosen by the RNG or something like a door closure problem occurs before the reels stop.

But there's a critical difference between today's reel-spinners and these craps machines. In the slot, the RNG has determined the outcome of the spin. On these craps machines, the machine has to read the number thrown by the dice. The dice are the RNG.

The old electro-mechanical machines of the 70s and 80s are an exact analog. Those machines had mechanisms to stop the reels randomly and those machines had to read the positions in which the reels stopped. They did not have a computer program determining where the reels would stop. Electro-mechanical machines have long since been removed from slot floors.

So I sevened out looking for a modern slot machine equivalent. There is a general EGD equivalent though — the machines that mimic roulette — but that doesn't help in trying to find a similar situation in a different type of machine.

In Nevada, any EGD that mimics a physical game must have the same probabilities as the physical game. Your chances for getting a royal flush on a video poker machine must be the same as those for dealing from a fair deck of cards. The odds on video craps, roulette and blackjack must be the same as those at craps, roulette and blackjack tables. The odds on these bubble craps machines must be the same as those at a craps table. The manufacturers can alter how much the bets pay, but the histogram of results of the dice throws must match the pyramid of craps.

No gaming control board, furthermore, would approve a machine that generates a new result because it didn't like the first one (see secondary decision on Universal slot machines). The house edge on these machine should be what you calculate it to be using what the bets pay.

Now, I have three questions. Has one of these machines ever re-rolled multiple times in a row? One would expect some situations in which multiple throws in a row would be unfavorable to the house.

Has a machine ever re-rolled and gotten the same number again? Does it keep rolling until it gets a different number? Or does the machine have only one chance to get a better outcome and it doesn't try multiple times because that would look suspicious?

How frequently do these machines re-roll? There must be many, many times when the results are unfavorable for the house.

I think these re-rolls are the result of a true malfunction. For some reason, the machine was not able to read the dice. If re-rolls happen frequently, players should report the machine to a slot floorperson.

Send your slot and video poker questions to John Robison, Slot Expert™, at slotexpert@slotexpert.com. Because of the volume of mail I receive, I regret that I can't reply to every question.

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