The gaming industry is big business in the U.S., contributing an estimated US$240 billion to the economy each year, while generating $38 billion in tax revenues and supporting 17 million jobs.
What people may not realize is that slot machines, video poker machines and other electronic gaming devices make up the bulk of all that economic activity. At casinos in Iowa and South Dakota, for example, such devices have contributed up to 89 percent of annual gaming revenue.
The par sheet determines the odds. Every modern slot machine is designed with a par sheet which specifies the weightings for each stop on the reel, including the blanks. That par sheet makes the odds and the house edge for a slot machine game a known quantity—for the casino. Gambling companies keep these par sheets under wraps, though, so.
Spinning-reel slots in particular are profit juggernauts for most casinos, outperforming table games like blackjack, video poker machines and other forms of gambling.
Electronic Slot Machines Odds Slot Machines
What about slot machines makes them such reliable money makers? In part, it has something to do with casinos’ ability to hide their true price from even the savviest of gamblers.
The price of a slot
An important economic theory holds that when the price of something goes up, demand for it tends to fall.
But that depends on price transparency, which exists for most of the day-to-day purchases we make. That is, other than visits to the doctor’s office and possibly the auto mechanic, we know the price of most products and services before we decide to pay for them.
Slots may be even worse than the doctor’s office, in that most of us will never know the true price of our wagers. Which means the law of supply and demand breaks down.
Casino operators usually think of price in terms of what is known as the average or expected house advantage on each bet placed by players. Basically, it’s the long-term edge that is built into the game. For an individual player, his or her limited interaction with the game will result in a “price” that looks a lot different.
For example, consider a game with a 10 percent house advantage – which is fairly typical. This means that over the long run, the game will return 10 percent of all wagers it accepts to the casino that owns it. So if it accepts $1 million in wagers over 2 million spins, it would be expected to pay out $900,000, resulting in a casino gain of $100,000. Thus from the management’s perspective, the “price” it charges is the 10 percent it expects to collect from gamblers over time.
Individual players, however, will likely define price as the cost of the spin. For example, if a player bets $1, spins the reels and receives no payout, that’ll be the price – not 10 cents.
So who is correct? Both, in a way. While the game has certainly collected $1 from the player, management knows that eventually 90 cents of that will be dispensed to other players.
A player could never know this, however, given he will only be playing for an hour or two, during which he may hope a large payout will make up for his many losses and then some. And at this rate of play it could take years of playing a single slot machine for the casino’s long-term advantage to become evident.
Short-term vs. long-term
This difference in price perspective is rooted in the gap between the short-term view of the players and the long-term view of management. This is one of the lessons I’ve learned in my more than three decades in the gambling industry analyzing the performance of casino games and as a researcher studying them.
Let’s consider George, who just got his paycheck and heads to the casino with $80 to spend over an hour on a Tuesday night. There are basically three outcomes: He loses everything, hits a considerable jackpot and wins big, or makes or loses a little but manages to walk away before the odds turn decidedly against him.
Of course, the first outcome is far more common than the other two – it has to be for the casino to maintain its house advantage. The funds to pay big jackpots come from frequent losers (who get wiped out). Without all these losers, there can be no big winners – which is why so many people play in the first place.
Specifically, the sum of all the individual losses is used to fund the big jackpots. Therefore, to provide enticing jackpots, many players must lose all of their Tuesday night bankroll.
What is less obvious to many is that the long-term experience rarely occurs at the player level. That is, players rarely lose their $80 in a uniform manner (that is, a rate of 10 percent per spin). If this were the typical slot experience, it would be predictably disappointing. But it would make it very easy for a player to identify the price he’s paying.
Raising the price
Ultimately, the casino is selling excitement, which is comprised of hope and variance. Even though a slot may have a modest house advantage from management’s perspective, such as 4 percent, it can and often does win all of George’s Tuesday night bankroll in short order.
This is primarily due to the variance in the slot machine’s pay table – which lists all the winning symbol combinations and the number of credits awarded for each one. While the pay table is visible to the player, the probability of producing each winning symbol combination remains hidden. Of course, these probabilities are a critical determinant of the house advantage – that is, the long-term price of the wager.
This rare ability to hide the price of a good or service offers an opportunity for casino management to raise the price without notifying the players – if they can get away with it.
Casino managers are under tremendous pressure to maximize their all-important slot revenue, but they do not want to kill the golden goose by raising the “price” too much. If players are able to detect these concealed price increases simply by playing the games, then they may choose to play at another casino.
This terrifies casino operators, as it is difficult and expensive to recover from perceptions of a high-priced slot product.
Getting away with it
Consequently, many operators resist increasing the house advantages of their slot machines, believing that players can detect these price shocks.
Our new research, however, has found that increases in the casino advantage have produced significant gains in revenue with no signs of detection even by savvy players. In multiple comparisons of two otherwise identical reel games, the high-priced games produced significantly greater revenue for the casino. These findings were confirmed in a second study.
Further analysis revealed no evidence of play migration from the high-priced games, despite the fact their low-priced counterparts were located a mere 3 feet away.
Importantly, these results occurred in spite of the egregious economic disincentive to play the high-priced games. That is, the visible pay tables were identical on both the high- and low-priced games, within each of the two-game pairings. The only difference was the concealed probabilities of each payout.
Armed with this knowledge, management may be more willing to increase prices. And for price-sensitive gamblers, reel slot machines may become something to avoid.
- Appendices
- Slots Analysis
- Miscellaneous
Introduction
The following table ranks the Las Vegas casinos according to the looseness of their video display reeled nickel slot machines. The returns are based on a sampling of five different types of machines. The data collected goes back as far as October 2001 so the information is a bit dated.
Las Vegas 5 Cent Slot Survey
| Rank | Casino | Average Return |
|---|---|---|
| 1 | Palms | 93.42% |
| 2 | Gold Coast | 92.84% |
| 3 | Sahara | 92.81% |
| 4 (tie) | Bourbon Street | 92.63% |
| 4 (tie) | Imperial Palace | 92.63% |
| 4 (tie) | Slots a Fun | 92.63% |
| 7 | Key Largo | 92.60% |
| 8 | Western | 92.57% |
| 9 | Ellis Island | 92.56% |
| 10 | El Cortez | 92.56% |
| 11 | Orleans | 92.56% |
| 12 | Circus Circus | 92.56% |
| 13 | Gold Spike | 92.55% |
| 14 | Fitzgeralds | 92.54% |
| 15 | Fiesta - Rancho | 92.53% |
| 16 | Arizona Charlie's East | 92.51% |
| 17 | Barbary Coast | 92.50% |
| 18 | Terrible's | 92.49% |
| 19 | Arizona Charlie's | 92.49% |
| 20 | Hard Rock | 92.47% |
| 21 | Town Hall | 92.47% |
| 22 | Longhorn | 92.47% |
| 23 | Riviera | 92.23% |
| 24 | California | 92.14% |
| 25 | Lady Luck | 92.10% |
| 26 | Nevada Palace | 92.06% |
| 27 | Plaza | 91.94% |
| 28 | Luxor | 91.92% |
| 29 | Paris | 91.92% |
| 30 | San Remo | 91.88% |
| 31 | Excalibur | 91.84% |
| 32 | Palace Station | 91.84% |
| 33 | Ballys | 91.82% |
| 34 | Las Vegas Club | 91.76% |
| 35 | Four Queens | 91.75% |
| 36 | Texas Station | 91.71% |
| 37 | Casino Royale | 91.67% |
| 38 | Boulder Station | 91.55% |
| 39 | Aladdin | 91.5% |
| 40 | O'sheas | 91.48% |
| 41 | Hilton | 91.40% |
| 42 | Boardwalk | 91.28% |
| 43 | New York New York | 90.99% |
| 44 | Horseshoe | 90.96% |
| 45 | Sam's Town | 90.89% |
| 46 | Santa Fe Station | 90.87% |
| 47 | Flamingo | 90.86% |
| 48 | Golden Nugget | 90.85% |
| 49 | Stratosphere | 90.8% |
| 50 | Tropicana | 90.71% |
| 51 | Golden Gate | 90.64% |
| 52 | Silverton | 90.57% |
| 53 | Main Street Station | 90.56% |
| 54 | Westward Ho | 90.40% |
| 55 | Fremont | 90.37% |
| 56 | Castaways | 90.36% |
| 57 | Monte Carlo | 90.24% |
| 58 | Stardust | 89.97% |
| 59 | Frontier | 89.91% |
| 60 | MGM Grand | 89.81% |
| 61 | Harrahs | 89.32% |
| 62 | Treasure Island | 89.32% |
| 63 | Mirage | 89.3% |
| 64 | Caesars Palace | 89.05% |
| 65 | Mandalay Bay | 88.87% |
| 66 | Rio | 88.72% |
| 67 | La Bayou | 88.26% |
| 68 | Mermaids | 88.26% |
| 69 | Bellagio | 87.42% |
| 70 | Venetian | 86.66% |
| 71 | Airport | 85.02% |
Excluded Casinos
The Suncoast and Rampart Casino in Summerlin do not allow playing slots and taking notes at the same time. I can not include any casino that prohibits the method in which I gather data.
Location Averages
The next table shows the average return by location.
Returns by Region
| Location | Average Return |
|---|---|
| Off strip | 92.07% |
| Downtown | 91.66% |
| Strip | 91.47% |
| Total | 91.74% |
The above sign can be found across the street from the Palms. Although I did the study Anthony Curtis published it in the LasVegas Advisor, which is how it become well known. The'...' in the sign encompases quite a bit of information,which was conveniently left off the sign. Actually the study only says that the Palms had the lowest nickel video slotsof the casinos surveyed in Las Vegas. The small print at thebottom says, 'Independent study conducted between November2001-February 2002 on Austin Powers, Fortune Cookie, Reel'em In, and Wheel of Fortune games. They left off LeopardSpots, and the study began in October.
Observations
Electronic Slot Machines Odds Against
There seemed to be no truth behind slot placement myths. Machines on the end of a bank did no better on average than those in the middle. There was also no correlation between return and proximity to such things as the main door, table game pit, high traffic areas, and low traffic areas.
Most casinos were very consistent in their slot returns.If one nickel machine had a return of x% then all others like it also returned x%. However some casinos did mix up loose and tight machines, most notably Treasure Island and the California casinos.
Methodology
A kind and anonymous source provided me with par sheets for the games in question. The EPROM (Erasable Programmable Read Only Memory) chip is what tells the machine the order of the symbols on the reel, in some cases how the stops are weighted, how much each winning combination pays, and any other pertinent information about how much the machine pays.It is up to the slot manager to select which EPROM chip to order according to the return percentage desired. On atypical game there might be about 8 different possible return percentages, ranging from about 85% to 98%.
Each of the different par sheets has five sets of distinct reels. On video display slots the stops are not weighted; in other words all stops are equally likely. The distribution of each symbol on each reel is what determines the theoretical return of the machine. For example a higher paying machine may have more of the higher paying symbols.
On the machine itself three consecutive symbols arevisible on five different reels. By comparing actualobservations of results to the par sheets it is possible todetermine which reels the machine uses, and thus which par sheet and which return. There are various three-symbol combinations that appear in at least one but not all par sheets. So if one of these combinations occurs on an actualmachine it narrows down the possible par sheets. By playingenough the player can narrow down the possible par sheets tojust one.
To help identify the unique combinations I wrote a computer program for each game, which had the exact reel order of all 5 reels of all the par sheets. The program then counted the number of par sheets with each possible three-symbol combination. If the number was greater than 0 and less than the maximum then that combination was identified along with the associated par sheets it belonged to.
It is then a matter of simply playing the game and comparing the outcomes to the list of partially unique combinations. It only takes about 5-10 plays per machine to narrow down the possibilities to just one par sheet.
The averages in the table are actually an average of averages. For each kind of machine at each casino I took an average return. Then I took the average of these averages over the five kinds of machines I tested for.
Slot Machine Definition
There is some confusion about what constitutes a 'slot machine' or 'slot.' My definition, and that of most gamblers, is a gambling machine with either actual spinning reels or video representations of the them.
People in the gaming business and regulators generally refer to a slot machine as any gambling machine, including reeled slots, video poker, video keno, video blackjack,etc.. For purposes of statistics both casino managers and regulators combine all the electronic gambling machines together. For example, the Slot Chart in Casino Player magazine and reports by the Nevada Gaming Control Board do not isolate just reeled slots but consider all electronic games a 'slot.' Therefore my return percentages should not be expected to agree with those reported by the casinos or regulators. As far as I know mine is the only source to isolate just the return of reeled slots.
Acknowledgements
I would like to thank Rob Feldheim for helping with the slot play and record keeping. Rob helped me with most of the casinos on the east side of town and part of downtown. I would also like to thank par Sheet Pete (not his real name)for providing the par sheets, without which this project would not have been possible.
Internal Links
Go to slot machine appendix3B (Jean/Primm slot returns).
Go to slot machine appendix 3D(Henderson slot returns).
Go to slot machine appendix 3E(Las Vegas quarter and dollar slot returns).
Go to slot machine appendix 3F(Montreal slot return).
Go back to slot machines.
External Links
Electronic Slot Machines Odds Nfl Week 11
The main-stream media has covered this study in depth. Here are links to some articles.
- Turning'em loose, an article that appeared in the Las VegasReview Journal on May 19, 2002, about the possible effectsof this study.
- One-Armed Bandit or Robin Hood?, an article by myself for Contingencies Magazine explaining the methodology, results, and weaknesses of the study.
- Play by the rules and the one-armed bandits will still win. Boston Globe article about slot machines, in which my Las Vegas survey is mentioned and my advice quoted. (cache)