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Cheating Fruit (Slot) Machines
ebbdr writes "Ever think that fruit machines cheat you? You would be right, at least in the UK. This article provides proof that fruit machine outcomes are predetermined and that the players inputs have little, if anything to do with it. And it lets you download the emulators and machine code required to test the hypothesis for yourself...."
It thinks it's running on a real physical fruit machine and acts in exactly the same way in all circumstances (except money doesn't actually come out of your PC).
Whew, thank god they put in that disclaimer, or I would've wasted the next 7 hours sitting here waiting for that one big payout from my PC.
for the love of god, does anyone have the ROMs for the machines in vegas?? i'd love to see what the hell is going on there
I can't seem to find -where- they got the ROM from? Seems like a crucial part of it to say what particular model/version.. I mean, even the screenshots have different quality graphics.
Not to say they're lying, but I'm not convinced of their "proof". Anyone else see something I missed?
The Random Number Generator (RNG) can be
made to change its percentage by simply changing it's seed number. There
are several ways this cam be done.
1) Change the Eprom Chip with a new program and/or seed number which any
computer technician can change a chip.
2) Use an Eprom that has a cyclic program that will keep changing the
seed number after predetermined numbers of cycles.
3) Posibly change the seed number through a signal from the master
computer or mainframe. There is no doubt that all these machines are
hooked up to the mainframe for monitoring and/or recording data for
expert review. It is known fact that comp cards and players records
are fed back to the mainframe, why not other data.
It is for this reason why I am an advocate for all Gambling to come under
a Federal or State controlled Gambling Commission. All of what I say is
not intended to infer that there is any tampering with slot machine
programs and controls. I can only say from my experience as a computer
programmer, that if the possibility exists, the probability resides.
Therefore only an astute Gaming Commission that can oversee these
computers and their control, will clear up this doubt and mistrust about
slot machines.
Heh, I remember the gool ol' Random Runner, before it had its programming upgraded. It would offer you exactly the same gamble as the article mentions, ie. two flashing lights with 'win' and 'lose', you hit a button and one of the lights stays on. What you did on the Random Runner was keep the button depressed. If you lost, too bad, but if you won... the next level bet would start but you'd win automatically, and the next bet, and so on.
Random Runners were popular with proprietors as well, as it was easy to obtain ROMs for these machines that would drastically lower the payout. Seeig this kind of machine is like a red flag for inspectors; they'll be sure to inspect the ROM in the machine.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
I've thought about this myself. The whole key to a slot machine or a fruit machine is that you need to be able to set the "payout" percentage, typically something high like 98%. 98% means that the player gets back $0.98 on every $1, assuming he plays an infinite amount of times.
The only way to guarantee this is by determining what the payout is as soon as the money's in the slot. The "pick high or low" and all of these other things are just meant to help keep the player interested, so that the player keeps playing.
Slot machines use other tricks, too: You can play on multiple lines, or you can play multiple coins for higher bonuses. Obviously the bonuses are multiples of the number of coins you play, so they have zero effect on probability. Multiple lines increases the probability you'll win per spin, but it doesn't affect the probability per coin, which is what matters to the proprietor.
This isn't a scam or cheating or anything like that. It is the same principle behind coin-op arcade machines: You pay to play. On a machine that has 98% payout and takes quarters, that means you pay (theoretically) half a cent every time you spin. In reality, you spend more or less than that depending on random outcomes, but over millions of plays on thousands of machines it means a good twopence on the pound for the Brits and two cents on the dollar for Americans.
Companies, that is. Not for the players.
A really convincing argument would be based on the ROM's internal code rather than on statistical analyses of the emulator output. After all, as long as an emulator is used, there is no way to know whether the ROM really has "cheater code" built in, or whether it's an emulator bug that is causing the analyses to come up wrong.
That's it. I'm no longer part of Team Sanity.
I keep telling people to play the change machines instead, at least you're gonna break even on each slot session.
Sorry, but no. On the machine tested, the pre-determined outcome of losing affects a chance to improve the winnings on an original bet. Either collect the 40p winning now, or gamble on high/low for the chance of a 60p win. Thus it is a gamble, which should carry with it the chance of actually winning.
As stated, this equates to selling raffle tickets where there's no winning number - dishonest and should be illegal.
~Cederic
From the article: "And in almost all cases, no matter what you chose, the result would be the same.",
Almost? Hmmmmm.
Anyway, what does it matter? Everyone knows that those machines have always given out less than they take in. What difference does it make what method they use? My dad has an old British slot machine that is 100% mechanical. Even it has dials inside that allow you to increase or decrease payouts to players. Anyone who buys a slot machine intends to make money with it. If it was a gamble to own the machine, nobody would. Vegas slots are all wired together to collectively "rip you off". Is this really a news flash to anyone?
If you can't afford to lose the money, you shouldn't put it in the machine.
Also, note that casinos are based on statistics, not on regulating individual payouts. While on the whole the casino will always win due to the massive scale it operates on, there is the opportunity for individual players to beat the odds and leave with more money than they came in with. Not allowing the player to win, with no element of chance whatsoever, is illegal almost everywhere. I imagine that this would fall under fraud laws at the very least, due to the fact that these machines are advertised as gambling devices based on random events.
That's it. I'm no longer part of Team Sanity.
I know it's a great /. tradition not to read the articles, but, for once, could you make an attempt?
To summerise the problem, the ROM shows that the outcome of slot machines is predetermined. In the acticle it gives an example:
"The machine has a number reel, with numbers from 1 to 12. On the reel a "10" is showing. Should you go Higher, or Lower?"
Apparently the machine doesn't pick a number at random from 1 to 12 and compares that to your guess of higher or lower. Instead it is predetermined whether you win or lose, so whichever button you press doesn't matter.
An emulator enables you to save and restore previous states, so that you can find out what would have happened. In this case, the author/s of the piece are saying that slot machines are predetermined things, at least in part.
This is probably illegal, as the machine is strongly implying that your guess will affect your chances (higher than 10 is less likely than lower than 10), which is shown to be untrue. It's almost like having a fixed dice game. In a fair game you'd expect to have 1/6 chance of winning when you roll a dice. In the above slot-machine example you'd expect a 1/6 chance of winning if you pressed Higher, and a 3/4 chance of winning if you pressed Lower, and this isn't the case.
A few years ago someone won over $600,000 from a machine at the Montreal Casino by analyzing patterns in the numbers that came up. The sequence repeated because the machine wasn't seeding the pseudo-random number generator properly. More info in Risks Digest.
The problem with digital gaming machines is that it is too easy for the programmer to add twists to the algorithms that tweak the odds. It seems odd that they would bother, since the laws of probability come out in the casino's favor, they don't need to tweak the algorithm, just do a little basic math first.
As I recall, the Nevada casinos are required to post the expected payout and odds on the machines. For example, the expected payout might be 98%. That means the casino collects on average 2 pennies every time a patron shakes the hand of a one armed bandit with a dollar bet. The casinos don't need to pull any tricks beyond calculating the expected payouts for the different states of the machine and make sure the expected payout is less than one.
It is disconcerting knowing that there are machines which go even further.
As I understand, a well run gaming commissions tries to assure that casinos don't bend the rules any further than that.
The example they have is that, if you follow the sequence on this page, the machine reaches a point that's supposed to be a gamble, but in fact you cannot win. And it's not because the output is predetermined, or the seed is the same and it happens to be a losing bet. It's a high/low gamble, so you should have a chance to win regardless of what the seed was. But if you pick high the machine picks low, and vice-versa. An 'honest' machine would pick the same number regardless of which button you picked.
Of course, the legal/ethical issue is more complicated than the simple mechanical issue. The basic problem is that machines are never fair, and cannot ever be fair because their purpose is to redistribute money from your pocket to the machine owner. The large number of people who seem to think that gambling is ever fair are deluded or naive. And the problem with the specific machine referenced above is that it has the extremely difficult task of mapping a percentage payout (they mention it's probably 70%) to a more fair operation (high-low with a pair of dice). Therefore, it has to cheat sometimes to ensure it doesn't payout too much. Which is perfectly legal, and really is the only way to do it. If they actually get a law passed saying that machines cannot cheat in any circumstance, it will mean the end of gambling, because no owner in their right mind would take a real gamble, where they could lose all that money they've been raking in.
First off, the article (yes, I read the article). The author's biggest peeve is that the outcome of the "double or nothing" option on the fruit machines is determined before the user even chooses. Big whoop. Whether the magic number is determined before or after you choose is meaningless; it does not affect the odds.
Second, a previous poster mentioned the RNG. In IGT slots (and I would imagine most modern ones), the RNG device is a super-sensitive measurement device that detects tiny vibrations in the chassis. This is a much better way of seeding a number generator than any software-based solution. No, banging on the chassis won't increase your odds, but it will cause the machine to tilt and will probably get the attention of a security guard. ;) Also, the machine uses this entropy to re-seed itself thousands of times per second, not just once in the beginning.
Lastly, there's the method for choosing if you win or loose. As soon as you press the "spin reels" button (or pull the handle on machine that still support that), the outcome is already known. Let me repeat: THE OUTCOME IS KNOWN before the reels start spinning. The actual spinning of the reels is just eye candy.
This part takes a bit more explaining: say each reel have three symbols on them (we'll call them A, B, and C; in reality, the reels have maybe a couple dozen). In this example, C is the most favorable; you get a jackpot if you get three C's. You would think that this would mean that you would have a 1 in 27 chance of hitting the jackpot (3^3). Nope. The internal mechanism works like so: Okay, you have 3 symbols on each wheel. Inside the program, there are 3 arrays of symbols, but the number of elements inside the array is much more than 3. Say these are the arrays:
- Reel 1: AAABBBBCCCCC
- Reel 2: AAAABBBBCCCC
- Reel 3: AAAAAAAABBBC
The machine picks a random element from each array. Do you see what's going on here? There are more Cs in the first reel array, making it very likely to hit a C on the first reel. Next is a slightly less chance to hit C again. The third time is nearly impossible. Yet it builds you hope up, thinking you're about to hit the jackpot.Is this deceitful? Yes. Does it prey upon the stupid? Yes. Is it illegal? Nope. These methods produce a certain payout percentage, and the techniques for producing them are "public" knowledge, usually regulated by your state's gambling office.
In conclusion, stick to blackjack.
Actually, the Vegas casinos don't cheat. They don't have to. Take roulette. They pay 35 to 1 on a winning spin. Now there's 38 numbers on an American wheel, 1-36 plus 0 and 00. That's 37 to 1 odds of winning a 35 to 1 payout. If the wheel's honest, the difference between those is 5.26%, which is the house's edge. If they don't cheat, they will get 5.26% of the money you play over the long run. This same thing applies to just about every other game on the floor, be it slots or blackjack or craps or whatnot.
It's only "just about", though. You can spot the exceptions by a simple question: who are you playing against? In craps and blackjack, for example, you're playing against the house. The house will win over the long run. In poker, OTOH, you're playing against the other players. The house just acts as bank and neutral dealer, and takes their cut from every pot. That's because in poker there's no house edge.
Sure, with computerized slots and such the casino could cheat, but why risk it? Nevada Gaming Control, believe it or not, is honest and all but incorruptible, and they've got enough experience that any cheating scheme a casino could use will be spotted pretty quick. The house gets their money, with honest games the nickel slots alone will pay the bills for the entire casino and everything else including the pit is pure profit. Why risk that gravy train for an extra fraction of a percent for maybe a year tops?
Though I doubt I am one of the friends of which you speak, I have written slot machine ("pokies") software for Tatts Victoria.
I can confirm that it's heavily regulated, and the RNG used is carefully analysed for randomness, with the the payoff tables (and to a lesser degree, the ordering of the symbols on "fruit machine" types) controlling the payout (which usually varies between 83% and 91%)
The results are only "pre-determined" at the time of the user starting the roll, but are completely random nonetheless. In other words, when the user pulls the arm (if the machine has an arm), the results of the roll (and any related results, e.g. from a "double-up") are randomly pre-selected, then the reels are spun to those positions.
What struck me most was the incredible security and redundancy the system has. In Victoria, the legal accounting requirements are very stringent, and the manufacturers themselves have a long list of attacks they have to be proof against (from long experience - everything from massive magnetic fields to electrical cattle prods have been used to defeat a slot machine's defenses).
For example, not only is the casing solid steel, locked and with mil-spec proofing against EMI, the CPU board and coin trays are both locked within separate steel compartments within the unit, and each requires a different key to unlock. All locks have failsafe mechanisms to record opening, and the cabinet door has a randomly-pulsed optical sensor as well.
Particularly, the win-loss game data is recorded into triple-battery-backed static RAM, in multiple CRC'd locations, with the same data being recorded simultaneously onto physical counters, printed in duplicate to a roll of paper (on some machines), and sent in real-time via encrypted LAN to a central host, which must verify all large payouts. Every coin and every game must be accounted for under any circumstance, particularly power failure in the middle of a game.
The coin sensors and payout mechanisms were equally sophisticated, and had to accurately deal with punters feeding large numbers of coins very rapidly into the machines, whilst still defeating "coin-on-a-string" style attacks.
It was an interesting project, but involved considerably more than I first expected. I can say that, after many all-nighters testing, I have come to truly dislike the sound of a slot machine :-/ (Ironically, for some years my next job required me to go to tradeshows in Las Vegas - from the very moment you step off the plane, you're assaulted by pokies on all sides)
Why would anyone engrave "Elbereth"?