Debunking Slot Myths: The Random Number Generator in Class III Gaming

[StatFreak]

MODERATOR NOTE: This topic split from "Another Secret to winning at SLots" and moved to Tech Talk board from eBay Auctions board.  SF

i saw some wierd stuff last night at the casino a $5 10x machine hit red sevan 10x 10x with 2 credits payed 50k then 2 hours later the same combo came up with 1 credit, the lady one 25k.....how can the exact same combo pop up within a few hours appart... wish that was me lol..... looser me played after the 25k hit thinkin it would pop up again.... gues what it didnt.....

The same combination could have come up on the very next spin after the first hit. It's just extremely unlikely. That's why we call slot outcomes random.

Meditate with me:
Random distribution does NOT mean even distribution
Watt?
Random distribution does NOT mean even distribution
Watt?

Ohm. 

All kidding aside, random distribution does NOT mean even distribution.  The position of the stars is an example of randomness. Are the stars evenly distributed in the sky? If I tell you that one star in 1000 is a certain brightness and color, would you question why you found two stars next to each other that were that same brightness and color and then spent a week trying to find another?

Why do humans insist on finding patterns in the stars where there are none? It's human nature. It's a survival instinct. We don't easily grasp randomness. We have an instinctive need to find patterns everywhere, and when there aren't any, we invent them.

The human need to see patterns in random events caused man to invent the constellations in the sky, and has built empires out of gambling houses. The best thing the casinos ever did for Roulette was to add that light board that indicates the last set of outcomes. Casinos saw a huge increase in revenue because players started betting perceived patterns in a game of independent trials.

The best thing any slot junkie can do to avoid losing too much is to stop trying to see patterns of wins and losses where there are none.

[staz]

so say you were gonna play that machine before it hit 5 minutes earlier would you have gotton the same winning combo or would the rng pop out a diff combo?

[StatFreak]

so say you were gonna play that machine before it hit 5 minutes earlier would you have gotton the same winning combo or would the rng pop out a diff combo?

If you pressed the spin button 1/100000 of a second later you would have gotten a different combo. Get it? 

Although computers can't be completely random, it's the human interaction that finally makes slot machines completely random. The numbers fly by at light speed and you snatch a set of three numbers from the sky at the precise moment you press the button. Twitch your muscle as you press the button, and you'll get a different part of the sky.

Within a few seconds, it's likely that every possible combination of outcomes has flown by.

[staz]

heres another? okay the rng zipps out combos in mili secs but now if you lower the percentage chip of a slot machine it reduces payouts and winning combos.... how does the rng adjust to that....does it skip high paying combos?

[StatFreak]

The rng make no adjustments at all. It is an independent process that is not connected in any way with the percentage.


Look at it this way: You roll one die and get a number from one to six. Does the die care what you do with the number?
If I say that you must roll a six to win, then the odds are 1 in 6 that you will win. If I say that you must roll a five or six to win, then the odds are 1 in 3 that you will win. I can also say that if you roll a six, you'll win 4 times your bet, or I can say that you'll win 3 times your bet. The die doesn't give a darn.

No adjustments to the die are necessary, as long as it's a fair die and is not loaded. I can completely control the payback by deciding how many outcomes are winners and how much you get paid when a winning outcome happens. The math will do the rest.

[theDotster]

Doesn't it just reassign the winning numbers, for example, if the machine picks 10 numbers:
1 thru 4 = losing symbol
5 thru 8 = small win symbol
9 and 10 = big win symbol

They would change it to this to reduce the payouts
1 thru 5 =losing symbol
6 thru 9 = small win symbol
10 = big win symbol

This is my basic understanding of how it works. Obviously the numbers used and combinations are much higher than this example.

Am I right?!?

[StatFreak]

Yes.  

[ROCKET]

so say you were gonna play that machine before it hit 5 minutes earlier would you have gotton the same winning combo or would the rng pop out a diff combo?

If you pressed the spin button 1/100000 of a second later you would have gotten a different combo. Get it?  

Although computers can't be completely random, it's the human interaction that finally makes slot machines completely random. The numbers fly by at light speed and you snatch a set of three numbers from the sky at the precise moment you press the button. Twitch your muscle as you press the button, and you'll get a different part of the sky.

Within a few seconds, it's likely that every possible combination of outcomes has flown by.

I  HAVE TO GIVE A COMPLIMENT WHEN ONE IS DUE >>TO STAT <<-GREAT POST AND
 ACCURATE AS HELL ON THE RANDOM & HUMAN INTERACTION!


now convert your words into lyrics for a song >>>>twitch that muscle<<< and >>>win the pie in the sky<<< ..you can be wealthy also lol

[staz]

i thought the rng new what numbers are gonna come out as soon as you put the money in the slot machine is there any truth to that?

[stayouttadabunker]

"RNG" means "Random Number Generator"...

It's a program in a chip that generates random numbers.

It has no clue what it's going to pick when you put money into the machine.
This program is running numbers all the time when the machine is powered up...


Inserting money into the machine only tells the machine that money was actually inserted and how much.
However, nothing else happens until you make a bet and depress the SPIN button.

Go back up and read Statfreak's answer as to what happens after you hit the SPIN button.

Did you ever see the cage with all the balls in it spinning and bouncing around
on t.v. at night during the news when they are picking
the Powerball numbers or some lottery numbers?
The balls are always bouncing around and around right?
That's the RNG!!!

Does it care or have a clue how much money you spent on lottery tickets or
know what numbered balls are going to fall out?

NO

The same (somewhat...) goes for a slot machine....
It doesn't care how much money you put into it nor
does it have any idea what symbols it's going to stop on until you push the SPIN button.

 

[jay]

This is kind of a irrelevant symantec.

It would be possible for the machine to choose the numbers when the first coin went in, the last coin, Bill, or the Max Bet button, or Bet 1 etc OR when the Spin button / Lever.
It could even use a combination of these factors. It would be up to the game manufacturers and could differ from machine to machine.

Irrespective the "true" randomness is the users action and not the machines choice.

Since the user has no "view" as to where the RNG is in its cycle, or even the length and given the speed of a microprocessor being in the mega or giga hertz range there is NO possibility that there is any predictability.


On a slightly different topic of randomness there have been some Roulette "cheat" devices created as of late. What they proport to do is to "predict" where the ball will land. You are supposed to enter in 1000 consecutive spins. This is to "calibrate" the device so it can figure out where the ball, and wheel have worn. You then enter in the aproximately velocity that the croupier is spinning the ball. I had even heard that there was supposed to be an Iphone app that could measure that speed and susbsequently predict what range is more likely to come up. While this is not supposed be an exact prediction it is supposed to vastly improve your odds.

Generally speaking single number picks on roulette pay 30:1.  There are only 38 numbers on the wheel. SO the theory goes that if you can narrow that range below 30 then you guarentee that by betting on all of the "possible" winning combinations you will be on the winning side.

Of course like any system there are flaws.... given that on average the wheel is spun just 45 times per hour. You would have to stand there entering in each number for 22 hours so even if the game is open that long you would be using more than one croupier and I also think that they switch up the balls every now and again. Of course standing there for 22 hours entering in each number into your iphone is not going to gather suspicion.....

Coming back to the topic at hand.... even as ridicilous as the roulette "cheat" is..... you don't get any kind of "electronic" wear that would aid in predictability of the RNG.

[staz]

im surprized no one out there ever tried makin a device that can controll rng numbers on a slot .....i guess he would be rich or in prison lol......

[Jim]

A question to all the numbers crunchers. This is how the payout theory was described to me: for a particular payout paytable say with 64 stops per reel. odds of hitting the jackpot 64x64x64=262144 possible combinations, only one of those is the jackpot combo. also it is one machine cycle. So they take all those combos and put them in a bingo cage(RNG), as the cage is rotated and a number is dispensed (hitting the spin button).after all those have been dispensed that is considered one machine cycle.The machine cycle is the part I have a hard time understanding, it is this cycle they have based there refusal to payout jackpots that have hit. "malfunction voids all payouts"  written on all IGT reel glass .The question, How does the RNG know which numbers have been dispensed,and which ones it can still generate to hold the payout percentage to the promised percent.

Jim

[knagl]

Jim-

The 'cycle' is pretty theoretical.  Yes, all of the balls are in the bingo cage, but after one is drawn it is put right back into the cage, eligible to be drawn again.  To keep things simple, let's say that there are 10 bingo balls in the RNG cage.  You can easily pick number 8 twice in a row, but over thousands of picks, the distribution of numbers 1 through 10 will pretty much even out.  There are 10 numbers in the cycle, but that doesn't mean that the cycle will repeat after 10 draws.

The term "cycle" is confusing to people, too, because they think that it means what you described -- that the jackpot is eventually "due" to hit if it hasn't been hit in "x" number of spins.  The reality is that it's not any more due to hit on the 10th spin or on the 262,143rd spin.

The question, How does the RNG know which numbers have been dispensed,and which ones it can still generate to hold the payout percentage to the promised percent.

The RNG doesn't care about what has been previously hit.  Let's change the example to 100 bingo balls (possible outcomes).  The RNG is constantly selecting a number (bingo ball) from 1 to 100.  Now let's say that we have a 90% payback program in there.  Balls 1 through 45 pay 2x your bet -- balls 46 through 100 are losers.

Welcome to my casino, here's a $100 bill for you.  Come play my one-coin, $1 machine.

If you made 100 plays and pulled balls 1 through 100 (in any order), you'd wind up with $90 back (you'd get $2 for balls 1 through 45, and $0 for the others).


Now, let's put a 92% chip in there.  Balls 1 through 46 are winners, while 47-100 are losers.  Same scenario.  You'd now have $92 back when you hit 1 through 46, and lose on 47 and above.

The difference is, as I mentioned earlier, is that you don't get to play every number in the cycle in order or only once per cycle.  In my 92% game, you could hit 1 through 47 100 times in a row since the balls keep getting put back into the cage, giving you a 200% payback in your short term play.  Over the life of my game however, with thousands or millions of draws, the game will eventually hold 8%, or pay back 92%.

[stayouttadabunker]

The way I've always understood it is that there really isn't any "cycle" -
that's a myth.
If there was a "cycle", it would be depicted in the PAR sheets...but they
only base their % value of the reel chips on 10 million pulls.
Is that a "cycle"?

In theory, all of the "number balls" are always in the "cage" (RNG)
and are continuously bouncing around waiting for word from the SPIN button.
The reel chip determines the % via symbol weighting. Like what Knagl was saying above^^^
A multi-combination of the microprocessor reading the reel paytable,
and the action of the very moment the player hits the SPIN button -
determines which symbols ( reel stops ) will fly out of the RNG "cage".

One reason that I believe that there's no "cycle" is because
I've seen the top Jackpot hit on back-to-back pulls on a S+ even though
the PAR sheet for that particular game showed only 1 Jackpot on the sheet through 10 million pulls...!
There's absolutly no way in the world the 1st Jackpot came from another previous "cycle" -
that would means the 1st jackpot came at the exact end of one "cycle"
while the 2nd Jackpot occurred on the very first pull of a new "cycle".
I find that extremely hard to comprehend.
Take the "cycle" out of the equation and things are much easier to understand.
 
Please correct me if I'm wrong on this...I'm only human...




ADDED>>> knagl answered while I was typing but the "weighting " of the symbols is also in his post.
I decided to leave my answer as is to see what differences we have of how the RNG is used in an S+.
As Jay said earlier, different companies used different ways of getting the "balls" to pop out.

[Jim]

Then what do they base a machine malfunction on? 

[stayouttadabunker]

Then what do they base a machine malfunction on? 

Good question Jim!

I wonder if that idea came from casino bosses in the past rather than the manufacturers?
I've also seen a cherry master-type of machine getting stuck and hitting the Jackpot pull after pull.
I've never seen it it happen on a slot other than the 2 Jackpots in a row.

The only way I see this happened was that the microprocesser "froze" or a transistor or diode
didn't allow the reel stepper numbers be released from the CMOS?
The CMOS DOES store the last so many hits in it's memory banks.
I don't think the CMOS has any say in what should come out on the next spin however -
it's just a memory bank for the accounting records & bookkeeping stuff.

Something ( a board component) temporarily failed I believe and I had to change out the MPU board.
I was never able to determine the exact cause though I also suspect it was a bad ( stuck) gate in the reel chip program perhaps?

[StatFreak]

WOW! It took me so long to write this that there have been six posts back on the slot subject, so I'll now include Jay's quote to keep this post in perspective.

Stat

...
On a slightly different topic of randomness there have been some Roulette "cheat" devices created as of late. What they proport to do is to "predict" where the ball will land. You are supposed to enter in 1000 consecutive spins. This is to "calibrate" the device so it can figure out where the ball, and wheel have worn. You then enter in the aproximately velocity that the croupier is spinning the ball. I had even heard that there was supposed to be an Iphone app that could measure that speed and susbsequently predict what range is more likely to come up. While this is not supposed be an exact prediction it is supposed to vastly improve your odds.

Generally speaking single number picks on roulette pay 30:1.  There are only 38 numbers on the wheel. SO the theory goes that if you can narrow that range below 30 then you guarentee that by betting on all of the "possible" winning combinations you will be on the winning side.

Of course like any system there are flaws.... given that on average the wheel is spun just 45 times per hour. You would have to stand there entering in each number for 22 hours so even if the game is open that long you would be using more than one croupier and I also think that they switch up the balls every now and again. Of course standing there for 22 hours entering in each number into your iphone is not going to gather suspicion.....

Coming back to the topic at hand.... even as ridicilous as the roulette "cheat" is..... you don't get any kind of "electronic" wear that would aid in predictability of the RNG.

Ah, Jay, you bring up a favorite of mine, not because of the cheat itself, but because of the true story behind the physics and computer grad students who got together in Santa Cruz in the 1970's to figure it all out. Their goal was to win enough at Roulette to fund the founding of a scientific community. They developed a shoe computer -- believe it or not -- using a 6502 processor, and while they were successful in practice, they made only a small amount of money in the casinos due to hardware problems, casino heat, and a few other twists. They determined that they had a 44% advantage over the house.

The group was headed by Doyne Farmer and Norman Packard, and included John Boyd and James P. Crutchfield. Their story is told in the book The Eudaemonic Pie by Thomas Bass (1985). Ironically, I did not discover the book through my interest in gambling, but through my studies of nonlinear dynamics (Chaos) in the 1980's, back when I actually had a memory.



With today's powerful computers, it would be simple to use UV lasers or other means to quickly determine the decay rate of the ball and the rotor and predict which "section" the ball will land in. The diamonds on the wheel are not ornamental, but are there to provide a scattering effect to randomize the final resting place of the ball. A proper program will take them into account when calculating the physics.

Also, different wheels have slightly different characteristics, so any good program would require tracking several spins of a wheel and recording its outcome to allow the program to compensate for that specific wheel's characteristics. However, this shouldn't take anywhere NEAR 1000 spins; perhaps a half-hour to an hour of tracking.

Using physics to accelerate (in time) the decaying orbit of the ball and the slowing of the rotor is not a ridiculous cheat. In fact, it's a solid method to beat roulette that uses physics, not a betting strategy.

Of course, the program being offered for the iPhone may be a Piece of S#^t -- and probably is if they require 1000 spins to customize their program for one wheel. I'm also not sure how an iPhone could accurately track the ball passing a certain point on the wheel housing, or do the same for a specific point on the rotor, unless they're asking the user to do it manually like the physicists did back in the 1970's, and they had to practice for months to get it right.


For anyone out there who thinks that this might be a good idea to try outside of a theoretical experiment, remember: IT'S A FELONY. Just walking into a casino with a cheating device is a felony in the state of Nevada, and the casinos today have sophisticated equipment to detect UV and IR signals and other electronic devices. iPhones and other toys aside, in a word: DON'T!

[jrr922]

Ok, so this has probably already been answered in a few other places but I can't find it, so bear with me...

Lets say we are playing a game (I usually stick to WMS's newer games) that have a STOP reels feature on the video slot- say Wizard of Oz or Zeus or something like that.  How does this affect the RNG when you disrupt the normal slot process like this.  It seems as though sometimes (although I know it is probably a false assumption) that by stopping the reels, you can change "your luck" and start getting some bigger wins!  When you stop the reels, does the exact combination that originally would have come up, actually still come up?

Thanks!

[StatFreak]

Jim,  RNG's pick numbers where 0 >= n < 1.

For Staz and others, that means numbers like this:
0.000123789
0.3416948970
0.9050000
0.010000002
etc.

As one can see, these numbers have nothing to do with choosing a number between 1 and 72 (or 256 or whatever). There is no cycle other than the inherent problem that no computer algorithm can be truly random. The slot manufacturers rely on human interaction to remove any possible bias.

These numbers have to be converted into a set of integers that match the desired range, and that takes place after retrieving the outcome of the RNG. Their exact method is unknown to me, but rest assured that it's one that is unbiased. Personally, I shift the decimal place of the random number by some arbitrary amount (though simple multiplication of a factor of 10) and use the remainder of modulo division by the span of digits I desire to obtain an outcome.

For example: To get a number between 1 and 15, multiply the random number by 1e8 and divide by 15. Modulo division will return a value between 0 and 14, so I add 1 to get a number between 1 and 15. If I need a number between 1 and 256, I do the same thing, but divide by 256.

Even if I get the same number from the RNG, I will end up with a different outcome depending on the range of numbers I need.

Example:

RNG outputs 0.34756079

1) I need to pick a number between 1 and 64:
    0.34756079 * 1e8 = 34756079. Modulo by 64 gives a remainder of 47. Add 1 and I get 48, which I will map to virtual stop 48 out of 64.

2) I need to pick a number between 1 and 72:
    0.34756079 * 1e8 = 34756079. Modulo by 72 gives a remainder of 23. Add 1 and I get 24, which I will map to virtual stop 24 out of 72.

3) I need to pick a number between 1 and 256:
   0.34756079 * 1e8 = 34756079. Modulo by 256 gives a remainder of 239. Add 1 and I get 240, which I will map to virtual stop 240 out of 256.

You can see that the same random number will put me in completely different parts of the virtual stop table, depending on how many stops I need. Modulo division guarantees that each of the final integers have an equal chance of appearing.


There is no need for "cycles". What's happening here is that laymen are confusing a statistical term for a lay term.

[jay]

All machine malfunctions voids pays and plays......

Some examples:
   Reel strips incorrectly fitted to the reel showing a valid payout but of course the machine does not recognise this......
   Reel tilt error - theoretically due to someone inserting a shim to stop the reel from spinning thus creating the appearance of a win....
   Hopper keeps paying out more coins than paytable says - theoretically due to the wrong chips / glass or mis programmed denomination.....

   Bill validator giving the wrong number of credits for a bill
   Progressive hitting on non top award......
   Progressive showing higher than expected award.....

The latter three I have a real problem with as this is a programming error by a casino employee and not a machine created error......

[StatFreak]

Ok, so this has probably already been answered in a few other places but I can't find it, so bear with me...

Lets say we are playing a game (I usually stick to WMS's newer games) that have a STOP reels feature on the video slot- say Wizard of Oz or Zeus or something like that.  How does this affect the RNG when you disrupt the normal slot process like this.
...

It doesn't. It is solely a gimmick designed to speed up your play, because the faster you play, the more money the casino makes. The outcome is determined within milliseconds of your initiating the spin -- long before you even see the beginning of the spin on the screen.

...It seems as though sometimes (although I know it is probably a false assumption) that by stopping the reels, you can change "your luck" and start getting some bigger wins!  When you stop the reels, does the exact combination that originally would have come up, actually still come up?

Thanks!

Yes. Video slots don't depend on physicality. There really are NO symbols in front of you: you are watching a computer animation of pixels. Just because there is a virtual stop listing in the program that determines which symbols will finally end up on your payline, that doesn't mean that the symbols that are animated (drawn) to fly by beforehand have to be in the same order as the virtual table, or even match it at all. They are only a show for the customer's entertainment.

The only symbols that finally matter for a multi-line video machine are the three that end up in the window when the spin is concluded. These are taken from the virtual stop table and must match the random outcome selected when you first initiated play. When you press STOP, what happens is that the rest of the animation (the "show") is cut short. From the moment you press stop, the computer begins drawing the final three symbols that indicate your outcome.

Watch very carefully the next time you play. You will see that the last three symbols drop into place just after you press the stop button, and that the symbols that are in the window at the very instant that you press stop go away (unless one of the reels just happens to be showing the correct symbols, which can happen every once in a while.)

[theDotster]

Ok, so this has probably already been answered in a few other places but I can't find it, so bear with me...

Lets say we are playing a game (I usually stick to WMS's newer games) that have a STOP reels feature on the video slot- say Wizard of Oz or Zeus or something like that.  How does this affect the RNG when you disrupt the normal slot process like this.  It seems as though sometimes (although I know it is probably a false assumption) that by stopping the reels, you can change "your luck" and start getting some bigger wins!  When you stop the reels, does the exact combination that originally would have come up, actually still come up?

Thanks!

The RNG has alerady done it's stuff at this stage. When you press the 'stop reels' button, you are simply cutting short the elongated display put on for your enjoyment.

If I was being suspicious I'd say this button was added to speed up your play and increase the number of spins per hour!

**oops, stat beat me to it!! **

[jay]

The other post didn't beat you too that.......

It was just a pre-programmed pixilization that was pre-determined before you hit the enter key....... 

[StatFreak]

The other post didn't beat you too that.......

It was just a pre-programmed pixilization that was pre-determined before you hit the enter key....... 

 

I've been so busy answering posts here that I haven't gotten out of the thread to see what else is happening on NLG today.