Slot machine

Slot machines in the Trump Taj Mahal

A slot machine (American English), poker machine (Australian English), or fruit machine (British English) is a certain type of casino game. Traditional slot machines are coin-operated machines with three or more reels, which spin when a lever on the side of the machine is pulled. The machines include a currency detector that validates the coin or money inserted to play. (The slot machine is also known informally as a one-armed bandit because of its traditional appearance and its ability to leave the gamer penniless.) The machine typically pays off based on patterns of symbols visible on the front of the machine when it stops. Modern computer technology has resulted in many variations on the slot machine concept. Today, slot machines are the most popular gambling method in casinos and constitute about 70% of the average casino's income.

History

Sittman and Pitt of Brooklyn, New York developed a gambling machine in 1891 that could be considered a precursor to the modern slot machine. It contained 5 drums holding a total of 50 card faces and was based on poker. This machine proved extremely popular and soon there was hardly a bar in the city that didn't have one or more of the machines bar-side. Players would insert a nickel and pull a lever, which would spin the drums and the cards they held, the player hoping for a good poker hand. There was no direct payout mechanism, so a pair of Kings might get the player a free beer, whereas a Royal Flush could pay out cigars or drinks, the prizes wholly dependent on what was on offer at the local establishment. To make the odds better for the house, two cards were typically removed from the "deck": the Ten of Spades and the Jack of Hearts, which cut the odds of winning a Royal Flush by half. The drums could also be re-arranged to further reduce a player's chance of winning.

The first "one-armed bandit" was invented in 1887 by Charles Fey of San Francisco, California, who devised a much simpler automatic mechanism. Due to the vast number of possible wins with the original poker card-based game, it proved practically impossible to come up with a way to make a machine capable of making an automatic pay-out for all possible winning combinations. Charles Fey devised a machine with three spinning reels containing a total of five symbols – horseshoes, diamonds, spades, hearts and a Liberty Bell, which also gave the machine its name. By replacing ten cards with five symbols and using three reels instead of five drums, the complexity of reading a win was considerably reduced, allowing Fey to devise an effective automatic payout mechanism. Three bells in a row produced the biggest payoff, ten nickels. Liberty Bell was a huge success and spawned a thriving mechanical gaming device industry. Even when the use of these gambling devices was banned in his home State after a few years, Fey still couldn't keep up with demand for the game elsewhere.

Another early machine gave out winnings in the form of fruit flavoured chewing gums with pictures of the flavours as symbols on the reels. The popular cherry and melon symbols derive from this machine. The "BAR" symbol now common in slot machines was derived from an early logo of the Bell-Fruit Gum Company. In 1964, Bally developed the first fully electromechanical slot machine called Money Honey.

Description

A row of "Wheel of Fortune" slot machines in a casino in Las Vegas. This specific slot machine is themed to the TV game show Wheel of Fortune

A person playing a slot machine purchases the right to play by inserting coins, cash, or in newer machines, a bar-coded paper ticket (known as "ticket in/ticket out" machines), into a designated slot on the machine. The machine is then activated by means of a lever or button, or on newer machines, by pressing a touchscreen on its face. The game itself may or may not involve skill on the player's part — or it may create the illusion of involving skill without actually being anything else than a game of chance.

The object of the game is to win money from the machine. The game usually involves matching symbols, either on mechanical reels that spin and stop to reveal one or several symbols, or on a video screen. The symbols are usually brightly colored and easily recognizable, such as images of fruits, and simple shapes such as bells, diamonds, or hearts.

Most games have a variety of winning combinations of symbols, often posted on the face of the machine. If a player matches a combination according to the rules of the game, the slot machine pays the player cash or some other sort of value, such as extra games.

There are many different kinds of gambling slot machines in places such as Las Vegas. Some of the most popular are the video poker machines, in which players hope to obtain a set of symbols corresponding to a winning poker hand. Depending on the machine, players can play one, 100, or more hands at one time.

Becoming more popular now are the multi-line slots. These slots have more than one payline. Reel slots commonly have three or five paylines, while video slots have 9, 15, 25, or even 100 different paylines. Video slots are themed slots, with graphics and music based on popular entertainers or TV programs (The Addams Family, I Dream of Jeannie, etc.) with a bonus round. Most accept variable amounts of credit to play with 1 to 5 credits per line being typical. The higher the amount bet, the higher the payout will be. Of course, there are the standard 3 - 5 reel slot machines, of various types. These are the typical "one-armed bandits".

One of the main differences between video slots and reel slots is in the way payouts are calculated. With reel slots, the only way to win the maximum jackpot is to play the maximum number of coins (usually 3, sometimes 4, or even 5 coins per spin). With video slots, the fixed payout values are multiplied by the number of coins per line that are being bet. In other words: on a reel slot, it is to the player's advantage to play with the maximum number of coins available. On video slots, it is recommended to play as many individual lines as possible, but there is no benefit to the player in betting more than one credit per line with regards to calculating the payout amounts. (There are some isolated cases where a video slot machine requires the maximum number of credits per spin to be inserted to win the largest payout, but those are the exception.) An example: On the "Wheel of Fortune" reel slot, the player must play 3 coins per spin to be eligible to trigger the bonus round and possibly win the jackpot. On the Wheel of Fortune video slot, the chances of triggering the bonus round or winning the maximum jackpot are exactly the same regardless of the number of coins bet on each line.

Larger casinos offer slot machines with denominations from $.01 (penny slots) all the way up to $100.00 or more per credit. Large denomination slot machines are usually cordoned off from the rest of the casino into a "High Limit" area, often with a separate team of hosts to cater to the needs of the high-rollers who play there.

Slot machines common in casinos at this time are more complicated. Most allow players to accept their winnings as credits, which may be "spent" on additional spins.

In the last few years, new slot machines commonly known as "multi-denomination" have been introduced. In a multi-denomination slot machine, the player can choose the value of each credit wagered from a list of options. Based upon the player's selection, the slot machine automatically calculates the number of credits the player receives in exchange for the cash inserted and displays the amount of available credits to the player. (For example, a player could choose to wager one dollar per game on a nickel slot machine.) This eliminates the need for a player to find a specific denomination of a particular slot machine; they can concentrate on simply finding the machine and setting the denomination once they decide to play.

Recently, some casinos have chosen to take advantage of a concept commonly known as "tokenization": 1 token buys more than one credit. A casino can configure slot machines of numerous different denominations to accept the same type of token. (For example, all penny, nickel, quarter, and dollar slot machines could be configured to accept dollar tokens.) This significantly reduces a casino's inventory costs and coin handling costs. A tokenized slot machine automatically calculates the number of credits the player receives in exchange for the token inserted and displays the amount of available credits to the player. When a player chooses to collect his credits (by pressing a "Cash Out" button), the slot machine will automatically divide the number of credits on the credit meter by the value of one token and return the result to the patron. Any remainder is known as "residual credits" and cannot be collected. Residual credits must be either played or abandoned.

Terminology

Bonus is a special feature of the particular game theme, which is activated when certain symbols appear in a winning combination. In the bonus, the player is presented with several items on a screen from which to choose. As the player chooses items, a number of credits is revealed and awarded. Some bonuses use a mechanical device, such as a spinning wheel, that works in conjunction with the bonus to display the amount won.

Candle is a light on top of the slot machine. It flashes to alert the operator that change is needed, hand pay is requested or a potential problem with the machine.

Carousel refers to a grouping of slot machines, usually in a circle or oval formation.

Coin hopper is a container where the coins that are immediately available for payouts are held. The hopper is a mechanical device that rotates coins into the coin tray when a player collects credits/coins (by pressing a "Cash Out" button). When a certain preset coin capacity is reached, a coin diverter automatically redirects, or "drops", excess coin into a "drop bucket" or "drop box".

Credit meter is a visual L.E.D. display of the amount of money or credits on the machine.

Drop bucket or drop box is a container located in a slot machine's base where excess coins are diverted from the hopper. Typically, a drop bucket is used for low denomination slot machines and a drop box is used for high denomination slot machines. A drop box contains a hinged lid with one or more locks whereas a drop bucket does not contain a lid. The contents of drop buckets and drop boxes are collected and counted by the casino on a scheduled basis.

EGM is used as a short-hand for "Electronic Gaming Machine".

Hand pay refers to a payout made by a slot attendant or cage, rather than the slot machine. A hand pay occurs when the amount of the payout exceeds the maximum amount that was preset by the slot machine's operator. Usually, the maximum amount is set at the level where the operator must begin to deduct taxes. A hand pay could also be necessary as a result of a short pay.

Hopper fill slip is a document used to record the replenishments of the coin in the coin hopper after it becomes depleted as a result of making payouts to players. The slip indicates the amount of coin placed into the hoppers, as well as the signatures of the employees involved in the transaction, the slot machine number and the location and the date.

Low Level or Slant Top slot machines include a stool so you can sit and play. Stand Up or Upright slot machines are played while standing.

Optimal play is a payback percentage based on a gambler using the optimal strategy in a skill-based slot machine game.

Payline is a straight or zig-zagged line that crosses through one symbol on each reel, along which a winning combination is evaluated. Classic spinning reel machines usually have up to nine paylines, while video slot machines may have as many as fifty.

Rollup is the process of dramatizing a win by playing sounds while the meters count up to the amount that has been won.

Short pay refers to a partial payout made by a slot machine, which is less than the amount due to the player. This occurs if the coin hopper has been depleted as a result of making earlier payouts to players. The remaining amount due to the player is either paid as a hand pay or an attendant will come and re-fill the machine.

File:Image(04).jpg

Display screen of a slot machine in tilt mode

Tilt In the old mechanical days, slot machines had tilt switches. While modern machines no longer have tilt switches, any kind of mechanical failure (door switch in the wrong state, reel motor failure, etc) is still called a "tilt".

Theoretical Hold Worksheet is a document provided by the manufacturer for all slot machines, which indicates the theoretical percentage that the slot machine should hold based on adequate levels of coin-in. The worksheet also indicates the reel strip settings, number of coins that may be played, the payout schedule, the number of reels and other information descriptive of the particular type of slot machine.

Weight count is an American term, referring to the dollar amount of coins or tokens removed from a slot machine's drop bucket or drop box and counted by the casino's hard count team through the use of a weigh scale.

Pay Table

Each machine has a table that lists the number of credits the player will receive if the symbols listed on the pay table line up on the pay line of the machine. Some symbols are wild and will pay if they are visible in any position, even if they are not on the pay line. Especially on older machines, the pay table is listed on the face of the machine, usually above and below the area containing the wheels. Most video machines display the pay table when the player presses a "pay table" button or touches "pay table" on the screen; some have the pay table listed on the cabinet as well.

Technology

Random number generator

It is a common belief that the odds on a machine have something to do with the number of each kind of symbol on each reel, but in modern slot machines this is no longer the case. Modern slot machines are computerized, so that the odds are whatever they are programmed to be. In modern slot machines, the reels and lever are present for historical and entertainment reasons only. The positions the reels will come to rest on are chosen by a Random Number Generator (RNG) contained in the machine's software. This is called "virtual reel" technology.

The RNG is constantly generating random numbers, at a rate of thousands to millions per second. As soon as the lever is pulled or the "Play" button is pressed, the most recent random number is used to determine the result. This means that the result varies depending on exactly when the game is played. A fraction of a second earlier or later, and the result would be different.

Some professional gamblers observe that the RNG does not actually generate random numbers. Indeed, all RNG (also called Pseudorandom Number Generator) will eventually repeat their number sequence. Some slot cheats, such as Ronald Dale Harris, a former slot machine programmer, discovered equations for specific gambling games like Keno that allowed them to predict what the next set of selected numbers would be based on the previous games played.

Payout percentage

Slot machines are typically programmed to pay out as winnings between 82 to 98 percent of the money that is wagered by players. This is known as the "theoretical payout percentage". The minimum theoretical payout percentage varies among jurisdictions and is typically established by law or regulation. For example, the minimum payout percentage in Nevada is 75 percent and in New Jersey is 83 percent. The winning patterns on slot machines, the amounts they pay, and the frequency at which they appear are carefully selected to yield a certain percentage of the cost of play to the "house" (the operator of the slot machine), while returning the rest to the player during play. Suppose that a certain slot machine costs $1 per spin. It can be calculated that over a sufficiently long period, such as 1,000,000 spins, that the machine will return an average of $950,000 to its players, who have inserted $1,000,000 during that time. In this (simplified) example, the slot machine is said to pay out 95%. The operator keeps the remaining $50,000. Within some EGM-development organizations this concept is referred to simply as "par". "Par" also manifests itself to gamblers as promotional techiniques: "Our 'Loose Slots' have a 93% Pay-back! Play now!" As an aside, the "Loose Slots" actually may describe an anonymous machine in a particular bank of EGMS.

A slot machine's theoretical payout percentage is set at the factory when the software is written. Changing the payout percentages after a slot machine has been placed on the gaming floor requires a physical swap of the software, which is usually stored on an EPROM but may be downloaded to Non-Volatile Random Access Memory (NVRAM) or even stored on CD-ROM or DVD depending on the technological capabilities of the machine and the regulations of the jurisdiction. Based on current technology, this is a time consuming process and as such is done infrequently. In certain jurisdictions, such as New Jersey, the EPROM is sealed with a tamper-evident seal and can only be changed in the presence of Gaming Control Board officials. Other jurisdictions, including Nevada, randomly audit slot machines to ensure that they contain only approved software.

In many markets where central monitoring and control systems are used to link machines for auditing and security purposes, usually in wide area networks of multiple venues and thousands of machines, player return must usually be changed from a central computer rather than at each individual machine. A range of percentages are preprogrammed into the game software and selected by configuring the machine remotely.

In 2006, the Nevada Gaming Commission began working with Las Vegas casinos on technology that would allow the casino's slot manager to change the game, the odds, and the payouts remotely via a computer. The change cannot be done instantaneously, but only after the selected machine has been idle for at least four minutes. After the change is made, the machine must be locked to new players for four minutes and display an on-screen message informing potential players that a change is being made.

Linked machines

Often machines are linked together in a way that allows a group of machines to offer a particularly large prize, or "jackpot". Each slot machine in the group contributes a small amount to this progressive jackpot, which is awarded to a player who gets (for example) a royal flush on a video poker machine, or a specific combination of symbols on a regular or 9 line slot machine. The amount paid for the progressive jackpot is usually far higher than any single slot machine could pay on its own.

In some cases multiple machines are linked across multiple casinos. In these cases, the machines may be owned by the machine maker who is responsible for paying the jackpot. The casinos lease the machines rather than owning them outright. Megabucks may be the best known example of this type of machine. Megabucks Nevada starts at $10,000,000 after a jackpot. (Prior to September 2005, Megabucks Nevada reset to $7,000,000.) The new penny Megabucks video game also has a jackpot that starts at $10,000,000.

Slot machines that are not linked to a large regional jackpot such as Megabucks usually have higher payout percentages, as linked machines have to take into consideration the large jackpot amount into their payout percentage calculations.

Near-miss programming

Because the reel display of modern slot machines is controlled by computer software, it is possible to make the slot machine frequently display combinations that are close to winning combinations. For instance, if the jackpot combination is "7-7-7", a slot machine could be programmed to frequently display "7-7-(non-7)". This can fool the player into thinking they "almost won", teasing them into playing more often.

This practice of showing combinations that are similar to winning combinations more frequently than would occur randomly is called "near-miss" programming. It has been ruled illegal in the U.S. states of Nevada and New Jersey. The Nevada Gaming Commission did review some machines with this type of programming and refused to authorize them.

There is a related phenomenon that is also sometimes called "near-miss". The chance of a winning combination appearing on a payline is controlled by the winning percentages programmed into the slot machine. However, the combinations appearing above and below the payline are all roughly equally randomly distributed. This means it is much more likely that a "winning combination" will appear above or below a payline than on the payline. Using the same example above, it is much more likely that a "winning combination" of "7-7-7" would appear on a line above or below the payline than the chance that it would appear on the payline.

The issue of a near-miss above or below the payline was also investigated by the Nevada Gaming Commission. They ruled that this was legal, so long as the "near-miss" above or below the payline was not specially programmed. In other words, the "near-miss" must be just as likely to occur as any other combination. The machine cannot be specially programmed to show "winning combinations" more frequently than other combinations above or below the payline.

The calculation is more complicated than implied here. The stops are not 'programmed' in the sense that their outcome is the result of a calculation. In fact, the reel strips (like a mechanical poker machine) are designed so that the machine will pay according to the relevant RTP.

Near-miss programming, where a near miss is innacurately displayed (i.e. the player is shown something that is not an accurate representation of the reelstrips) is not allowed in Australia either. Due to this, regulators use stop motion cameras to audit manufacturer's practices.

Regional variations

Row of slot machines inside Las Vegas airport.

United States

In the United States, the public and private availability of slot machines is highly regulated by state governments. Many states have established gaming control boards to regulate the possession and use of slot machines. Nevada is the only state that has no significant restrictions against slot machines both for public and private use. In New Jersey, slot machines are only allowed in hotel-casinos operated in Atlantic City. Several states (Illinois, Indiana, Iowa, Louisiana, Mississippi, and Missouri) allow slot machines (as well as any casino-style gambling) only on licensed riverboats or permanently anchored barges. Delaware allows slot machines at three horse tracks, they are regulated by the state lottery commission. For a list of state by state regulations on private slot machine ownership, see U.S. state slot machine ownership regulations.

Native American casinos

Native American casinos located in reservations are not permitted to have slot machines unless the tribe first reaches a pact with the state in which it is located (per Indian Gaming Regulatory Act). Typically, a pact entitles the state to receive a percentage of the gross revenue from slot machines.

Slot machine classes

The Following statements are generalities, not actual laws for every state. There is no federal law governing slot machines, so these classifications may vary from state to state.

Some states have restrictions on the type (called "class") of slot machines that can be used in a casino or other gaming area. "Class III" (or "traditional") slot machines operate independently from a centralized computer system and a player's chance of winning any payout is the same with every play. Class III slots are most often seen in Nevada or Atlantic City and are sometimes referred to as "Vegas-style slots".

"Class II" slot machines (also known as "Video Lottery Terminals" or "VLTs") are connected to a centralized computer system that determines the outcome of each wager. In this way, Class II slot machines mimic scratch-off lottery tickets in that each machine has an equal chance of winning a series of limited prizes. Either class of slot machines may or may not have a player skill element.

In general a game must have all characteristics of a Class II game to be a Class II game. Any characteristic of a Class III game makes it a Class III game. The casino pays a fee to the state for each Class III game and can only purchase so many Class III licenses. There is no such restriction for Class II games. Class II games are not so nearly regulated by the state.

Class II game characteristics

1. The player is playing against other players and competing for a common prize.
2. There is certain to be a winner in each game. The game continues until there is a winner.
3. In a given set there are a certain number of wins and loses. Once a certain combination has happened it cannot happen again until a new batch is initiated. This is most obvious in scratch card games that come in a pack. Once a card has been pulled those winning combinations cannot occur again until a new pack of cards is installed. One game is dependent on previous games.
4. The player must be an active participant. They must recognize events as they occur and must recognize when they have won and announce their winning. Bingo is an excellent example here.
5. All players play from the same set of numbers as they are announced.

Class III game characteristics

1. The player is playing against the house.
2. There is a very real possibility that the player may lose the game.
3. Each game is independent of previous games. Any possible outcome can occur in any game.
4. Wins are announced automatically.

Slot clubs

Many American casinos offer free memberships in "slot clubs", which return a small percentage of the amount of money that is bet in the form of "comps" (complimentary food, drinks, hotel rooms, or merchandise), or sometimes as cash back (sometimes with a restriction that the cash be redeemed at a later date). These clubs require that players use a card that is inserted into the slot machine, to allow the casino to track the player's "action" (how much the player bets and for how long), which is often used to establish a level of play that may make a player eligible for additional comps. Comps or cash back from these clubs can make a significant difference in the maximum theoretical return when playing slot machines over a long period of time.

Australia

File:Poker machine queen of the nile.JPG

Queen of the Nile (manufactured by Aristocrat), one of the most popular Australian poker machine games, also very popular in some American casinos

Slot machines in Australia are generally referred to as "poker machines" or "pokies", but are officially termed Gaming Machines. Australia has seen changes in regulations leading to proliferation of gaming machine venues in various states, most notably New South Wales, Victoria and Queensland. Various bodies, including religious organisations and welfare groups, claim that this has increased levels of "problem gambling".

Australian-style gaming machines use video displays to simulate physical reels, usually five. These machines have additional bonusing and second-screen features such as free games and bonus levels. They also allow for multiple lines (up to 50) or multiple ways (up to 243) to be played. This higher level of complexity offers greater opportunity of rewards for players.

Gaming machines are found in casinos (approximately one in each major city) as well as pubs and clubs (usually sports, social, or RSL clubs). There are suggestions that this high level of accessibility may be linked to problem gambling; however, the precise nature of this link is still open to research. The first Australian state to legalize this style of gambling was New South Wales in 1956 when they were made legal in all registered clubs in the state.

Laws governing gaming machines in Australia are controlled at the state level and as such, those laws vary between states. In the state of Queensland gaming machines in pubs and clubs must provide a return rate of 85% while machines located in casinos must provide a return rate of 90% [1]. Most other states have similar provisions.

United Kingdom

Row of old fruit machines in Teignmouth Pier, Devon

Slot machines are usually known as fruit machines and AWP (Amusement with Prizes) in Britain. Fruit machines are commonly found in pubs, clubs, arcades, and some take-away food shops. These machines commonly have 3 or 6 reels with around 16 or 24 fruit symbols printed around them. These reels are spun, and if certain combinations of fruit appear, winnings are paid from the machine, or subgames are played. These are very similar to slot machines seen in casinos and elsewhere around the world, but the term "fruit machine" is usually applied to a type of machine more commonly found in pubs and arcades. These games have lots of extra features, trails and subgames with opportunities to win money, usually more than can be won from just the reels. However, the jackpots from these fruit machines are strictly limited. An old-fashioned word for these machines can be 'Didlers'.

Currently in the UK, the cost of an individual game may not exceed 50p. The maximum payout for an individual game depends on the type and the location of the machine, but is typically £25 in pubs where people under the age of 18 are not allowed entry. It is known for machines to payout multiple jackpots, one after the other (this is known as a streak) but each jackpot requires a new game to be played so as not to circumvent the maximum payout. The minimum payout percentage is 70% in Britain, with pubs often setting the payout at around 78%. Private members clubs are allowed "club machines", which have higher jackpots and are allowed to charge more per game.

These machines also operate in a different fashion to American slot machines; whereas slots are programmed to pay a percentage over the long-run, there is no reason why a jackpot cannot be paid straight after one has already been won - this is because over the long-run the percentage payout will be the same. However, in the UK, a fruit machine takes on an amount above its payout percentage before winning, so if a payout is 95%, a machine will make the player lose £10 before paying out £9.50. As such, it is sensible to watch for people playing these machines but not winning as the likelihood of a win increases. This, however, is called Sharking.

This type of fruit machine is popular across Europe (in the countries where they are legal), and very popular in countries such as the Czech Republic, Russia, and Ukraine.

It has been alleged by the Fairplay campaign that UK fruit machines employ fraudulent techniques in which gambles and chances which appear to be random are in fact pre-determined and cannot be affected by player choices.

...at this point, you'll have gambled the win up to £25. However, the machine doesn't want you to gamble any further. If from the 5 you select "High", the machine will spin in a 3 and you'll lose. If, on the other hand, you select "Low", the machine will spin in a 9 and you'll lose...

The claims centre around the emulation of fruit machine hardware on computers, which allow for the machine's RAM state to be saved at a particular point and replayed making a different choice. The fruit machine industry has hit back at the allegations. Currently the issue has supposedly been considered by the UK Gaming Board (now the Gambling Commission) and warning notices and possibly modifications are to be put in place, though it is unclear as to whether this has happened. This is in fact the law now in the UK, and all machines carry a warning notice informing the user that the machine may at times offer the player a choice in which they have no possible chance to win.

Japan

Japan has a relatively new involvement in slot machines, roughly since after the American occupation during the World War II era. Most machines can be found in Pachinko parlors and the adult sections of amusement arcades, known as game centers.

The machines are regulated with IC chips, and have six different levels changing the odds of a "777". The levels provide a rough outcome of between 90% to an astonishing 160% (200% if using skills). Indeed, the Japanese slot machines are "beatable". The parlor operators, naturally set most of the machines to collect money, but intentionally place a few paying machines on the floor so that there will at least someone winning, encouraging players on the losing machines to keep gambling.

Despite the many varieties of the machines, there are certain rules and regulations put forward by the "Security Electronics and Communication Technology Association", an affiliate of the National Police Association (NPA). For example, there must be three reels. Also, all reels must be accompanied by buttons which stop these reels, no more than 15 coins can be paid out per plays, credit meter cant go higher than 50, 3 coin maximum bet, etc.

Although a 15 coin payout may seem ridiculously low, the regulations allow "Big Bonus" (~400-->711 coins) and "Regular Bonus" modes (~110 coins) where these 15 coin payouts occur nearly continuously until the bonus mode finished. While the machine is in bonus mode, the player is entertained with special winning scenes on the LCD display, and energizing music is heard, payout after payout.

Three more unique features of Pachisuro machines are "Stock", "Renchan", and "Tenjoh". On many machines, when a bonus is awarded, it is kept in "Stock", and not immediately given to the player. Instead, the "Stock" is released when some future rare random event(s) occur. Many current games, after finishing a bonus round, set the probability to release additional stock very high for the first few games. As a result, a lucky player may get to play several bonus rounds in a row (a "Renchan"), making payouts of 5000, even 10,000 coins possible! The lure of "Stock" waiting in the machine, and the possibility of "Renchan" tease the gambler to keep feeding the machine. To tease him further, there is a "Tenjoh", a maximum limit on the number of games between "Stock" release. For example, if the "Tenjoh" is 1500, and the number of games played since the last bonus is 1490, the player is guaranteed to release a bonus within just 10 games.

Because of the "Stock", "Renchan", and "Tenjoh" systems, it is possible to make money by simply playing machines on which someone has just lost a huge amount of money. This is called being a "hyena". They are easy to recognize, roaming the aisles for a "Kamo" ( "sucker" in English) to leave his machine.

In short, the regulations allowing "Stock", "Renchan", and "Tenjoh" has transformed the Pachisuro from a low-stakes form on entertainment just a few years back to the hard-core gambling it has become in 2006. Many people may be gambling more than they can afford, and the big payouts also lure unsavory "hyena" types into the gambling halls.

To address these social issues, a new regulation (Version 5.0) has been adopted in 2006 which caps the maximum amount of "Stock" a machine can hold to around 2000--3000 coins worth of bonus games. Moreover, all Pachisuro machines must be re-evaluated for regulation compliance every 3 three years. Version 4.0 came out in 2004, so that means all those machines with the up to 10000 coin payouts will be removed from service by 2007. Only time will tell how these changes will affect the Japanese Pachisuro industry.

Common misunderstandings

"Hot" and "Cold" machines

Standard slot machines do not get "hot" or "cold". The odds of hitting a winning combination are determined by a random number generator contained in the machine's software and is exactly the same with every spin. Such slot machines are never "due to be hit" if they haven't paid out a jackpot in a while. (Exception: UK-style AWP and Japan-style Pachisuro machines are progressive which means chances of winning will increase over time if the machine has not paid any wins out. Many also "force" wins on players in order to meet the payout percentage).

Placement

There is a science to the placement of slot machines on the gaming floor, but the highest paying machines are not necessarily placed in high-traffic areas. Typically, machines of similar payback percentages are grouped together, with 1% or less difference from machine to machine in the group.

Payout changes

• In most jurisdictions, casinos cannot alter the machine's payout percentage by time of day, day of week, or remotely via a computer.
• Using a slot club card does not affect the machine's payout percentage. The card just allows the casino to keep track of the amount wagered by a player and issue complimentaries accordingly.

Missed opportunities

Consider these two scenarios:

• You leave a machine. Another player comes up and immediately hits a jackpot. You think, "If I had played just one more time, I would have won that jackpot."
• A machine returns a higher jackpot for playing more coins. You play fewer coins, and a winning combination appears. You think, "If I had played more coins, I would have won more money."

In both cases, you did not "miss" an opportunity to win. The results of modern slot machines depend on exactly when you play them. It is very unlikely in either case that you would have received the same result if you had played just one more time or just one more coin. This is because the random numbers being generated are constantly changing thousands of times per second. It is impossible to assume that the instant you would have made the play would be the same for the other opportunity, thus getting different results from the machine. See Random Number Generator above.

Addiction

Main article: Problem gambling

Slot machines, like other gambling devices and games, can be addictive to some individuals.

Trivia

• The first Liberty Bell slot machine can be found at the Liberty Belle Saloon & Restaurant on 4250 S. Virginia, Reno, Nevada. Brothers Marshall and Frank Fey opened the restaurant Nov. 20, 1958. The Fey's grandfather, Charles Fey, invented the first three-wheeled slot machine, and the restaurant has a collection of more than 200 antique machines. The Liberty Belle closed on March 17, 2006 and the location was recently purchased by the Reno-Sparks Convention Center which is located nearby.

• The Liberty Belle's slot machine collection was due to be auctioned off on July 8, 2006 at the Reno-Sparks Convention Center.

• The first MegaJackpot system was introduced by International Game Technology in 1986. It is known as a Wide Area Progressive system.

• The term "One-Armed Bandit" was also used in slang in the US Navy and other navies to describe a single-armed missile launcher, such as the US Navy Mk. 13. Missile launchers with aiming arms are now becoming obsolescent as vertical launching system-equipped ships replace them in large numbers.

Bibliography

• Brisman, Andrew. The American Mensa Guide to Casino Gambling: Winning Ways (Stirling, 1999) ISBN 0-8069-4837-X
• Grochowski, John. The Slot Machine Answer Book: How They Work, How They've Changed, and How to Overcome the House Advantage (Bonus Books, 2005) ISBN 1-56625-235-0
• Legato, Frank. How to Win Millions Playing Slot Machines! ...Or Lose Trying (Bonus Books, 2004) ISBN 1-56625-216-4

See also

• United States state slot machine ownership regulations
• Progressive jackpot
• Video poker
• Video Lottery Terminal
• Quiz machine
• Pachinko
• Tommy Glenn Carmichael

External links

• HowStuffWorks: Slot Machines
• How Slot Machines Work
• Slot Machines explained
• Slot Machine Analysis
• [http://slot-tech.com
• [http://slottechforum.com
• [http://slotnotes.net