1. Regulations Regarding Slot Machine Payback Amounts In Nevada City
2. Regulations Regarding Slot Machine Payback Amounts In Nevada Casinos

No, the odds are the same regardless of the time of day.

Most slot machines usually offer an incentive to play the maximum coins. For example two coins may pay 2,000 on the jackpot but three coins will pay 5,000. So if there an economy of scale incentive, then the return is higher with a max-coin bet. However, I should mention that most casinos tend to increase the theoretical return on their slots as they go up in denomination. So, you may be better off betting one coin on a $1 machine than four coins on a quarter machine.
My advice on slot selection is to play a simple smaller game. Nothing with fancy signage or a huge screen. Ultimately, it is the players that pay for that in the form of a lower return.

For Nevada information call (800) NEVADA-8. The Nevada Gaming Control Board does not break down its slot statistics by individual properties/houses/casinos. Rather, they are classified by area. The following are indicative payback percentages listed by bet value machine and by area. In Nevada, for example, state regulations require that slot machines be set to pay back at least 75 percent of the money that people bet into them. This means that in every casino in Nevada there are some machines programmed to pay back at the low end, some programmed to pay back at the high end, and the majority programmed to pay back every.

Interesting question. I'm sure that didn't refer to the payback percentage, 37% would be way too low. The 'hit frequency' is the probability that the player wins anything.

I'm pretty sure that the odds on Megabucks are the same everywhere. It is a 'proprietary game,' meaning the casino and slot maker (IGT) share in the profits. As I understand it, such propriety games are generally set to a return of about 88% by the slot maker, and the casinos do not have the option for a looser or tighter version.
The Wheel of Fortune game, with the big jackpot, I believe is also a proprietary game. Video poker odds are dictated by the pay table. For example, a 9-6 Jacks or Better game will pay 99.54%, assuming optimal strategy and an infinite amount of play, regardless of where the machine is or number of number of hands the player gets on the draw.

You're right, it is impossible for me to know without Microgaming giving me the details on how their reels are weighted. I have asked some of the major software companies for such information, but thus far nobody has volunteered anything. However, I can tell you that the average payback for all slots at the Golden Palace for the month of March 2000 was 95.67%. This information is available at the Golden Palace web site, click on the Price Waterhouse Coopers monthly payout review.

I would assume that the odds are the same at all Microgaming casinos. All casinos probably contribute money to the same account from which the jackpot is paid. This way, the individual casino from which the jackpot was hit does not have to reach into their own pocket when somebody wins. Mid-level payouts are probably paid by the casino itself.

The minimum applies to every machine. Someone with the Gaming Control Board in Carson City, Nevada, told me that every machine in the state must meet minimum payback percentages. The only exception, he said, are on some antique machines in Virginia City.

Unlike most slots, this game has different types of wins according to the number of coins bet. The first coin enables the player to win the small frequent 'bar' wins, from 2 to 60. The second coin enables larger 'seven' wins from 100 to 500. The third coin doubles the wins for sevens, except it also qualified the player for the progressive jackpot for three sizzling sevens.
The ways these games are programmed is to give the player a slightly higher return on each additional coin bet. For example, the first coin might have a return of 92%, the second 93%, and the third 94%. You seem to think the return for one coin would be very low, due to the small wins, but those wins happen more often than the wins for sevens.
In Nevada, regulations require slots to theoretically pay at least 75%. Even the games at the airport, which are very tight, still pay at least 85% or so. I'm quite sure that the return for any number of coins bet in Blazing Sevens conforms to industry norms.

In general Indian casinos are self-regulated. There is generally a tribal commission that will hear disputes, but ultimately the members of the commission know which side of their bread gets buttered.
Don't assume any kind of minimum return on the slot machines. However, ultimately economics would dictate that a return too low would be sensed by players, who would be unlikely to return if they consistently lost too much money too quickly. It would also be bad business, and time consuming, to loosen and tighten the slots like a yo-yo.
Your sound level hypothesis sounds interesting, I never thought of that.

The casinos don't actually program the casinos to pay a certain percentage, but determine the weighting of the reels so that the theoretical return is whatever they wish. In the short run, the actual return can be either much higher or lower than the theoretical return. However, the laws of mathematics dictate that the actual return will get closer to the theoretical return the greater the number of trials.

Each frame in these video slots is weighted equally. Any given line is equally likely to produce any given combination. Thus, the return is the same regardless of the number of coins played.

Royal flush - 840
Four deuces - 200
Wild Royal - 20
Five of a kind - 12
Straight flush - 9
Four of a kind - 5
Full house - 3
Flush - 2
Straight - 2
Three of a kind - 1
I would do this myself, but I am unable to use the necessary software, as I am not a windows user.

Physically all you have to do to change the return of the slot machine is change the EPROM chip inside. Assuming the casino manager had all the EPROM chips, which I think they sometimes do, they could make the change themselves. However in a major jurisdiction the change would have to be reported to the gaming authorities, not to mention internal paperwork. The random number generator is constant, it is what the program does with the random numbers that determines the return.

In general the higher the coinage the better the rate of return is. However in my own research I have seen plenty of exceptions, notably dollar machines that paid less than quarters.

I don’t know whether the chances of winning were better or not. They worked the same way as they do now except each stop on each reel had an equal chance. The very early ones didn’t pay money but chewing gum, which explains the bar symbols (sticks of gum) and fruits (flavors) on some modern slot machines.

I’ve been asked about these North Carolina slot machines so many times I’m tempted to fly there just to see them for myself. Yes, if they did give the probability of each symbol for each reel then an optimal strategy and a return could be fairly easily calculated. However I have never actually seen such a table and have never worked out the odds.

I just had an eye-opening experience at Casino Windsor. No where do they publish their percent payback on slots. However, that aside, I was going to play quarter (my comfort level) video poker. I was really taken aback when I put up the paytable. They were 5/4 machines. I am talking Jacks or better was only 5 coins on a full house and 4 coins on a flush. I looked at about 20 machines and only found one that paid any better and that was a 6/4 machine.

As I stated, I am not a mathematician but I think that payback percentage must be in the very low 70s. Needless to say I didn’t play video poker there because I know that the longer I would have played the greater the loss I could have expected with the house taking approximately $30.00 from every $100.00 put through the machine. That is not a gamble with some expectation of winning, it is a sure loss for players. On the Detroit side of the river, MGM Grand has their machines at 7/5. Not really great but a whole lot better than 5/4.

Could you please tell me the exact percentage payback on the 5/4 and 7/5 machines. Since none of the area casinos post their average payback on slots I am (and this is dangerous) assuming that their reel slots payback the same percentages. Best regards.

Actually with perfect play the 5/4 pay table return 92.78%. Still one of the worst pay tables I have ever heard of. Have you tried the Greektown casino in Detroit? I don't know what games they have but I do know they have had security remove several winning video poker players from the building, including a old lady who hit a royal on a machine with a 97% pay table. They must have something good enough to warrant throwing winners out for.

First lets clear up what the term 'hold' means. For purposes of electronic games it is the theoretical return the game is set to. In both video poker and slots each play is random and independent of all past plays. The laws of mathematics dictate that even with independent trials the as the sample size gets larger the actual return will tend to get closer to the theoretical mean, or the hold. So contrary to popular belief a machine never goes hot or cold to get back in balance. Never mind the term 'cycle.' It is a poorly named industry term for the number of possible outcomes of the random number generators inside the machine. Unfortunately the term has trickled down only to confuse low level employees and players alike. Contrary to popular myth there are no cycles and again each play is equally random and independent of all other plays.

Not often. Contrary to popular myth the casinos don’t tighten the machines on weekends or whenever it is busy. Here in Las Vegas the casinos have to fill out a form every time they change the percentage on each game. Most slot managers I have spoken with have a policy on what coinage is set to what return. I tend to think the most likely reason to change the percentage would a change in ownership and/or management, which do not happen often.

The 96.7% applies to total money bet and transaction fees generally only apply to deposits and/or withdrawals. Players generally circulate through the same money and thus bet much more than they deposit. As I discussed in the September 18, 2005, column a player could bet through about 1.5 million dollars with a $10,000 bankroll and betting $5 at a time in blackjack. In this case the casino would make their profit based on 1.5 million in bets but pay expenses based only on $10,000.

From what I hear anything you can configure at the machine you can configure remotely through the server. This would include the theoretical return percentage. However most casinos report that changing the theoretical return of a slot machine necessitates a lot of paperwork.

Even if it were effortless to move the slot machine return up and down, it strikes me as a conspiracy theory to think the casinos would do that on a player by player basis. Living here in Vegas, I hear all kinds of theories about the lengths the casinos go to in order to win, like pumping in oxygen and playing a subsonic mantra that says 'lose lose lose.' These are just urban legends. Most casinos correctly believe that if you give the player a good experience and a fair gamble then he will keep coming back. As they say, you can only slaughter a sheep only once, but you can shear it many times. (My webmaster, Michael Bluejay, who is a vegetarian, tried to get me to use this analogy instead: 'You can seize all of a sheep’s money only once, but you can force it to take you bowling many times.')

Regulations Regarding Slot Machine Payback Amounts In Nevada City

According to the Nevada Gaming Control Boards that means that every slot machine in that bank must be set to a theoretical return of at least 97.4%. Popular opinion has it that only one machine must be set to 97.4%, or that the overall average must be 97.4%. However, I am taking a firm stand that both notions are wrong, at least here in Nevada.

It depends. If the slot play may be used in any machine in the casino, including video poker, then it can be worth 99 cents on the dollar or more, depending on the video poker offerings. For example, the MGM Mirage casinos award $1 in free slot play for every one point earned. It can be used in any machine in any casino connected to the MGM Mirage player card. Most MGM Mirage properties offer 9/6 Jacks or better, so the value of $1 in free slot play is worth 99.54 cents, with correct strategy.

However, sometimes free slot play must be done on particular promotional machines that don’t accept money. The value of this kind of free play is hard to estimate closely, but generally very little. For example, the Las Vegas World used to sell “$1000” vacation packages for $400. Of the alleged $1000 value $600 was in promotional slot machine play. In his book “Million Dollar Video Poker,” Bob Dancer writes that he did this deal numerous times over, and estimates the value of the free slot play to be about ten cents on the dollar.

It will show the specific return of the game you played.

Let’s assume 10.8 for the standard deviation, which I get from the Red, White, and Blue game described in my slot machine page. The standard deviation of the mean over n spins is standard deviation per bet divided by the square root of n. In this case, 10.8/10,000^0.5 = 0.108. The difference between 93% and 91% over 10,000 spins is just 18.5% of one standard deviation. To get the standard deviation of the mean to just 2% you would need a sample size of 291,600 spins. The standard deviation in slots will vary substantially, so take these figures with a grain of salt.

No, there isn’t. I don’t like it any more than you do. I think the player should be allowed to know the rules and/or the odds about what he is gambling on. Others have asked me if invoking the state Freedom of Information Act. I tend to doubt it would help or apply. As far as I know, the only place with such a right to know might be Holland. I’m told in Amsterdam information about the virtual reel stripping is indicated in little cards on the machines. You could in theory calculate the odds with that information and the pay table.

'Anonymous' .

No. To get an estimate of how loose a casino's slots are you would want to know the ratio of money returned to money bet. This ratio would typically be about 92%. Telling you only the amount paid out is not useful at all. Consider the Circus Circus claim of paying out $26 million a month. They don't disclose how much players bet to get that $26 million. What if they bet $35 million? That would be a return of 71.43%, which would be awful.
In conclusion, I don't know whether to be angry over what I consider to be deceptive advertising or depressed that people fall for it.

The EPROM chips, which control the theoretical return percentages on slots, are generally changed very rarely. It would be bad business to loosen and tighten the slots according to the day of the week. For any given casino there is some optimal return to maximize profit. Wherever that is, a smart slot manager would find that point and then just leave the EPROMS set to that return.

1. Given the random number generator stops on a virtual Cherry say, how does the machine make the physical reel stop on a visible cherry? I mean technically speaking.
2. Does this explain how pachinko machines from Japan can electronically alter payout percentages without altering the physical reel symbols?
3. Suppose the machine decides its time for a BAR, the only BAR on the third reel, just as one passes the pay-line. Does it let the reel go one full turn and catch it on the next go-round?
4. Suppose a physical reel stops on a paying combination by mistake, i.e. a symbol other than the virtual one pre-ordained. What happens then?

Thanks much.

Let me answer each question individually.

Regulations Regarding Slot Machine Payback Amounts In Nevada Casinos

1. It is just programming code that dictates to the machine that if the virtual reel stops on a cherry to make the actual reel stop on a cherry. There are actual notches on the reels which may help the machine to stop in the right place. If you peer through the glass at and angle you can sometimes see these notches. However, I am not an engineer and am not sure exactly how the machine knows to stop at just the right moment. It just take it for granted that it can.
2. Theoretically, the casino could change the payout on a slot machine with just a remote control. The remote control could tell the machine to use any previously programmed virtual reels. Practically speaking, the major casinos need to get approval from the gaming authorities to change the payback of a machine. If they did get such authorization all a slot technician has to do is replace a chip inside the machine, known as an e-prom. This happens infrequently and would not warrant the expense of a remote control.
3. It seems to me the reels spin at least several times before stopping.
4. In the unlikely even that happened, then I think it would trigger a malfunction and the bet would be voided.

No, that information won’t help you at all. Your odds are always the same on every spin, regardless of the counters.

They are some kind of counter. As a player they won’t help you at all, just ignore them.

To answer your question I asked a well connected gaming consultant and he said Nevada regulations state that one stop on a reel can not be weighted more than six times more than either stop next to it. So if a jackpot symbol were weighted by 1 and both bordering blanks were weighted by 6 then there would be 12 near misses for every one time the reel stopped on the jackpot symbol. This would be the maximum allowed near miss effect. My own results detailed in my slot machine appendix 1 back up this theory well. The red double seven was the highest paying symbol and I saw the blanks above and below it about 5 to 6 times as often:

Double Strike Actual Results

The same source said that New Jersey and Mississippi likely have adopted the Nevada regulations.

There is a 'look up' table that maps the various random numbers to stops on the reels. However I wasn’t sure how they go from there to actually determing what the player won. So I asked a former slot machine mathematician, who asked not to be identified, about this one. Here is what he said, 'Your first idea is correct. The position on each reel strip is independently selected via the RNG. The code then examines the symbols along each bet-upon payline to determine winning outcomes. Scatter awards could also be determined this way. ALL of the major video-based slot manufacturers do it this way. You could view the algorithm as a big series if-then-else’s but actual implementation might be a bit more eligant.' I hope that helps.

p.s. After this column appeared I received another e-mail regarding this question. It is rather long so I offer this link.