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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...."
I don't know how it is in Britain, but it's well-known that U.S. slot machines pay a fixed percentage that is set by the house. The symbols that come up on the reels aren't random, and aren't advertised as such. So I'm not entirely clear why this is news.
...
Maybe these kinds of machines are different in Britain, or maybe they're advertised differently
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.
They aren't lying, the ROMs are likely to be originals, and the machines' owners are not breaking the law.
Confused?
The law (at least around here) does not state that the machine has to be truly random. The law merely specifies a minimum average payout. The machine probably has to cheat in order to meet the lawful minimum payout, without (obviously) exceeding it by too much.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
I think this quote from the article demonstrates that kind of behaviour:
The pseudo-code would probably look like this:
(How do I create indents? :)
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.
It's certainly not a hoax, emulators of (UK) fruit machines and roms for them have been around for a while now, it's not like this site is the only place you can get them.
Something I have a vague recollection of from my lectures in Psychology can be applied to gambling machines.
Apparently, the most effective way to get someone to keep doing something is to provide a reward at random intervals [of button pressing, lever pulling etc.], centered around some average. It doesn't matter how large the reward is, just as long as it is something. Most studies were carried out on rats, but humans are so similar to rats that you might as well generalise.
For "Fruit Machines", you can encourage people to play by rewarding them randomly, but on average, say, about every 20 button pushes. The amount returned from the machine doesn't really matter in terms of how addictive the machine will be, so a 99% payout would work as well as a 80% payout.
But then again, who ever listened to a psychologist and believed what they were saying?
Ask me about repetitive DNA
Not if you own the board. Spare parts from slot machines are pretty easy to come by. There is a whole trade in used machines, cabinets, etc.
Slot machines are pretty common in the UK, most pubs have one. It is no more difficult to come across parts legally than it is to find parts for any other common appliance.
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Try http://dotcrimeManifesto.com/
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.
Apparently the 'proof' that sliot machines, fruit machines as those wacky brits choose to call them, is that, if you 'freeze' the state of a fruit machine at some point and then repeat the next step, the machine will generate the same outcome.
No, that's only half of it.
The machine gives you a choice (typically "high" or "low" in the examples they gave), but you will always lose, NO MATTER WHICH ONE YOU CHOOSE.
A deterministic slot machine is one thing: even if it simply paid out exactly 1 in every 10,000 spins, that would be legal.
What's illegal (according to the authors) is that the machine presents a game and says that it's a gamble: if you choose the correct alternative (high or low) you will double your winnings, otherwise you will lose. But the machine has already decided that you will definitely lose no matter what you pick, and that's what they think is illegal under U.K. law.
In other words, playing the game at all is a gamble. If you play, you might win (no matter what you press), or you might lose (no matter what you press). However, the game is presenting choices in the middle of the gameplay as "gambles" when in reality they don't affect the outcome.
It was explained to me by my boss at one point in time that machines in the U.S. (not sure of the locale, sorry) may be required a payout a certain percentage of the time, BUT, the machine plays ITSELF when no-one is using it.
Any wins which occur at that time are LEGALLY counted as customer wins...
see this comment (#6141133) below.
.sig wanted: Must be concise, funny, and display my cleverness.
I work at an online casino, and this is exactly how our games work. When you press the button to spin the wheels, the result of the game is decided then and there. This includes the results of any bonus games. The amount of your win was decided by the spin, and the bonus game itself will show whatever it needs to to show you that total amount.
Our terms and conditions for each slot spell this out however, stating the the results of the bonus games have no effect on the actual win amount. Presumably other online casinos work the same way, and I don't think it's too big an extrapolation to state that most physical slot machines work the same way.
I write software for slot machines. I can confirm that it is not the display that awards prizes, but the prize that selects that display shown to the user.
Who is the first person to handle a fledgling slot machine game? The product manager? The software engineer? The graphic artist? No, it is a mathematician, deciding the selection and frequency of pay-outs. A table of prizes is created and the reels of the game (the number of stops on each reel is tweaked to adjust the outcome) are displayed to correspond to the probability of a given pay-out.
When you see those billboards that advertise "the loosest slots" what they mean is that the software at that particular casino has been configured to pay out, say, 95% instead of only 94%.
The gambling industry is the only one I know of to set it own profitibility. The earnings of the casinos are assured as long as the customers play.
All this said, so what? Even if they don't understand the math behind the games, most people are intuitively aware that "luck" is not a basis for a business plan, and that the casino always wins in the end. I don't see what all the furors is about.
Scanning the files with less and strings shows typical patterns. But not knowing the cpu at this point makes it hard to progress. Copyright notice prominent at the end of the rom image
EASTENDERS COPYRIGHT OF MAYGAY MACHINES LIMITED 1996 BREACHING COPYRIGHT RESULTS IN PROSECUTION
The readme file is informative:
Thanks to.. Harvey & Russ - Classic
Russ - Photos Taken of Original machine
Skeet - Tidied Up Above Photos
Mike - Enhanced Reel Bands
Harvey - Playtesting & Suggestions
www.dxcellent.com
Note how Russ gets credit for a picture of a machine. Makes me think they got the roms out of a trash pile cause they didn't have a fully functional machine to look at. Fun
I would not be surprised to learn that casino owners program machines to play with themselves to change the odds or other nasty tricks. Anything for that extra edge. American businessmen are becoming scummier and scummier with each passing day.
Of course the whole industry is dependent on having a certain amount of honest casinos who let the occasional gambler to win. Without any wins, there is no way to establish that precious little addiction that the casinos crave. As such the casinos will probably dig themselves into a tragedy of the commons situation where more and more casinos opt to cheat until they kill their industry. But I guess people are stupid enough to bet on lotteries with a 60% expected pay out.
In Nevada, the source code for any legal game is reviewed by the state Gaming Control Board before approval. So it's pretty tough (but not impossible!) for a programmer to add such twists. And when a really big jackpot is hit, the casinos have internal audit personnel that tear the machine apart to check for any sort of tampering. At this time, they also review the chips to make sure they are approved chips. Many Nevada casinos advertize 98% payback, but by law, the payout can be as low as something like 78% (not sure the exact amount, but it's down in the 70's); which means on the average, the casino makes a lot more money than just a few pennies. The payback for some table games is even worse (some are better... in Blackjack, the odds constantly shift back and forth between the player and the casino). I work for a company that makes a computer system that interfaces to slot machines; I get to play slots everyday... A good job if you can get it ;-)
I also have friends that work in casinos and for actual slot manufacturers. I'm not a mathmetics expert, nor even a gaming expert, but I do sorta know a bit about it.
If anyone's interested, you can check out all the rules and regulations at:
http://gaming.state.nv.us/
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"?
The emulator sounds like it is operating correctly - the game, and all double-up/nudge results, are determined at the start of the game. The article proves that this is pre-determined, but not that players are being ripped off. The nudge results (at least in the slot machine software I wrote) were exactly a fifty-fifty chance, regardless of choice (and this was a legal requirement - slot machines are games of pure chance; no user skill element is allowed, regardless of how it appears).
The game on the page you mention wins four nudges and loses the fifth, but the page itself is misleading. It suggests choosing Low then High then Low again in order to win the first four games, but it fails to mention that it does not matter what you choose! You can choose High then Low then High again, and the numbers will be different but the result will be the same - you will always win the first four games and lose the fifth, regardless of your choice.
(Disclaimer: I'm too lazy to download the emulator and confirm this myself, but logically (and from my experience) it must be so - I'd happily make a bet of it ;-)
Why would anyone engrave "Elbereth"?
BTW, I used to travel to Las Vegas to work several times a month, and often chatted with a "slot mechanic" who lived in Phoenix. He fixed the machines, set the odds, and was absolutely forbidden to set foot in a casino in Nevada except in the company of a casino official (they usually brought the slots to him, except in cases of a huge payout). He told me which machines to play ... the ones at the ends of the aisles along both sides of the route leading from the front door to the check-in desk are usually set to pay off small and often. The casino wants incoming guests to see winners. For bigger, but far less frequent payoffs, it's the machines in the middle of the rows.
I think that your math may be bad as well...Read this this.