Advantage gambling, or advantage play, refers to legal methods, in contrast to cheating in casinos, used to gain an advantage while gambling. The term usually refers to house-banked games, but can also refer to games played against other players, such as poker. Someone who practices advantage gambling is often referred to as an advantage player, or AP.
A skillful or knowledgeable player can gain an advantage at a number of games. Blackjack and other table games can usually be beaten with card counting, hole carding, shuffle tracking, edge sorting, or several other methods. The players most skilled in these techniques have been nominated to the Blackjack Hall of Fame. Some video poker games, such as full pay Deuces Wild, can be beaten by the use of a strategy card devised by computer analysis of the game and often for sale in casino gift shops. And similar to the Blackjack Hall of Fame, there is an internet "Video Poker Hall of Fame". Some progressive slot machines and lotteries can eventually have such a high jackpot that they offer a positive return or overlay when played long term. Some online games can be beaten with bonus hunting.
Sports and horse betting can be beaten by placing arbitrage bets, which involve placing bets at different bookmakers who are offering different lines. Many online sports books now offer bonuses like free bets or free money. These bonuses usually come with a stipulation that the bettor place a certain number of bets. For example, a site may offer a bettor $50 free if they deposit $100 and place a total of $1000 in bets. These can reduce the vig taken by the house or even offer the bettor a small advantage.
Another form of advantage can be found by betting the "middle" on a sports event. This situation occurs when two bookmakers are offering different lines on the same event, or if a bettor has placed a bet and the bookmaker changes the line. The bettor simply takes the most favorable lines at each bookmaker, and if the result of the contest is between the numbers, or in the "middle", then the bettor wins both bets.
For example, Bookmaker A lists the Jets to be a 4-point favorite over the Bills. Bookmaker B has the Jets as just a 2-point favorite. The advantage player may bet the Bills +4 with Book A and then the Jets -2 with Book B. If the Jets win by 3, the advantage player collects on both bets. If the Jets win by either 2 or 4, the advantage player collects on one winning bet and the other "push." And if the Jets win or lose by any other total, the two bets cancel out, leaving the advantage player to pay only the vigorish on the bets. Given typical 10-cent lines, a middle need only win 1 time in 21 to break even, which is a realistic goal - the middle is always a plausible result since it is based on the actual strength of the teams. Middling is an example of line arbitrage.
Using special offers provided by bookmakers it is possible for a skilled bettor to put the odds in their favour. Special offers may include; cashback on specific events, enhanced odds and comp points. To profit from these specials, a skilled bettor will use betting, laying and dutching to create their own book on an event that may not guarantee profit but will still put the odds in their favour instead of the bookmaker(s) involved. Sign up bonuses are also classed as special offers and can be used in a similar way to lock in a profit regardless of the result using the principals of matched betting.
Betting exchanges offer advantage players a chance to make a larger profit than possible with bookmakers because exchanges charge commission only on the net winnings in a particular betting market. One way to make money on the exchanges is "trading" - in the above example, the Jets might be a favorite decimal odds of 1.90 to defeat the Bills. If a "trader" thinks these odds too long he may bet $1000 on the Jets, and should he prove correct and the odds on the Jets get shorter, "lay off" by laying, say, a $1016 bet against the Jets at 1.87. If the Jets win, he collects $900 on his bet on the Jets and pays out approximately $884 on the bet he laid against the Jets. If the Jets lose, he loses his $1000 stake on the Jets but keeps the $1016 stake on the bet he laid against the Jets. Either way, the "trader" makes a $16 profit and he will pay a commission only on that profit (usually not more than 5% or 80 cents in this example) for a net profit of $15.20 regardless of the result. Of course, if the odds go the wrong way the "trader" may lose money but most exchanges do not charge a commission in the event of a net loss.
Poker can offer a long-term advantage to a skilled player because it is played against other players and not against the house. The casino usually takes a rake or a time charge. Whether a poker player can win enough from the game to cover the rake and make a profit depends not only on the player's skill, but on the opposition's lack thereof - the degree of difficulty can vary widely from casino to casino. Tables with relatively easy opposition are referred to as "soft."
There is another advantage to playing poker as opposed to games where play is against the house: since the house has no direct interest in the outcome of a poker game, successful poker players can operate openly without risk of being banned by casinos.
There are many ways of making advantage during the game. One advantage is to watch your opponents and their reactions, especially their facial expressions; example is that a person can make a certain face expression or a gesture if the person is bluffing, therefore making it easy to detect a bluff and call the bet or even raise it. If the player is making nervous reactions after calling or raising a bluff (etc. squeezing fists, sweating, nervous face expression), no matter how small they are, if detectable, the bluff can be confirmed. For this reason, many professional poker players wear sunglasses and caps to prevent other players from reading their gestures and expressions, therefore giving them an advantage.
Other ways of noticing a bluff is the amount of money in the certain bet, especially during flops and turns, while bluffing during river is a rare occasion. Some players usually notice the bluff in the amount; if the amount of money is too large for a safe bet, especially if the raised pot is very close to All in or the pot is All in, the bluff will be called. When a raised pot is also suspicious but it is not big enough to be a certain bluff, advantage players usually visualize every possible card pair that the suspected bluff player could have (etc. pair, two pairs, three of a kind). Another way to notice a bluff is the round in which the bluff is made; inexperienced bluff players usually bluff during flops, while the advanced ones bluff during turns, and some even during rivers, although bluffing during river is a very risky move.
Read main article: Dice control
Experts disagree about whether or not an advantage can be gained at some other games. One example is dice control. Authors Stanford Wong and Frank Scoblete believe that by setting and throwing the dice in a certain way players can alter the odds at the game of craps enough to gain an advantage.
In the Japanese game of pachinko, there are numerous purported strategies for winning, the most reliable of which is to use inside information to learn which machines have the highest payout settings. Because of the "Stock", "Renchan", and tenjō 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 their machine in a favorable mode.
"Angle shooting" is another type of advantage play. "Angle shooting" refers to legal but possibly unethical ways to beat casino games. One way to get an advantage at a casino is "hole carding" where a player tries to look at the dealer's hole card in blackjack and then uses that information to play his hand differently. Taking advantage of incorrect payouts is another example of angle shooting. Not correcting an inexperienced dealer who pays 2 to 1 on a blackjack instead of 3 to 2 is an example of taking advantage of an incorrect payout.
Angle shooting may also be undertaken in poker. If, for example, an angle shooter attempts to bluff at the end of a hand, and is called, he may announce his hand as a flush even if it does not qualify. If the calling player throws away his hand, the angle shooter will claim the pot with his non-flush, claiming he made an honest error in announcing his hand. Similarly, angle shooters might hold on to a losing hand, hoping the winning hand will be mucked at showdown due to player or dealer error, and then claim the pot. A simple way to avoid being taken advantage of by angle shooting at poker is always protect one's hand and always let the "cards speak"; that is, turning over one's hand at the showdown for all to see.
Comp hustling can be another form of advantage gambling. Players who play games with a low house advantage or low bet size such as penny slots, can get more than their expected loss in free items from the casino. Many advantage players also take steps to maximize the comps they receive from their play.
Casinos sometimes take measures to thwart players who they believe pose a threat to them, especially card-counters or hole-card players. Some casinos tolerate card-counters who do not bet large amounts, who are not good at counting, or who do not use a large betting spread. Some countermeasures include shuffling more frequently, imposing betting limits, "backing off" the player by asking him not to play blackjack any more, or asking the player to leave the casino. In New Jersey, a player may not be asked to leave a table for counting cards, although the house may still impose betting limits or shuffle sooner. Players caught counting cards or hole-carding ultimately may find themselves listed in the Griffin Book and become unwelcome in most casinos. The Griffin Book was sued, but there are other substitutes today. In the past, video poker and skillful progressive slot machine players were rarely ejected for winning, but the practice is common today. They may have their comps reduced or eliminated. Skillful sports bettors, known as "sharps", may have their betting limits reduced and may not be allowed to take advantage of bonuses at online sports books. Instead, skillful sports bettors may rely on "runners" to place and collect their bets.
Craps players are often stopped from playing if the dice fail to bounce off the back wall of the table.
Advantage players abide by the established rules of the game and thus, in most jurisdictions, are not regarded as committing fraud against the casino. So, while they may face the above casino-imposed sanctions, they are able to operate without the threat of criminal prosecution for their behavior. This is not the case in all jurisdictions however and some advantage players have reported more aggressive countermeasures being taken even in well known gambling locations like Monte Carlo.