What is card counting?
Card counting has nothing to do with remembering every card that has been played, that's more a feat of memory. Although the card counting systems take many forms, one of the most popular and simplest is the high-low count. Each card is assigned a positive, negative or neutral value:
The player keeps a running total of the count, adding or subtracting as each card is played. The player raises their bet according to the positive strength of the count. The count also determines how to play each hand. For example, if the deck is strongly positive the player is more likely to draw face cards, so may profit by playing a more cautious strategy.
- 2, 3, 4, 5, 6 = +1
- 7, 8, 9 = 0
- 10, J, Q, K, A = -1
Is it illegal to count cards?
No. A card counter is using information available to everyone at the table, so they are not regarded as cheating. But if a casino suspects a player of counting, they will usually ask them to play a different game, or to leave the casino.
Are there any other casino games where the player can win?
No. Probability theory was developed by mathematicians studying gambling games. Casinos and bookmakers use probability theory when setting odds, and make sure they are always slightly in their favour.
Without this edge, casinos would not exist. Occasionally a casino may make a mistake and change the rules of a game or increase payouts, skewing the mathematical advantage to the player. When this happens, alert players flock there. The casino will swiftly change the rules back.
How hard is it to card count?
The actual counting is simple. The player just needs to keep track of how many high or low cards leave the deck. Making money from counting is, however, a completely different matter. Even playing the perfect game and betting exactly optimum amounts, the player advantage is so small that there is always a reasonable chance of losing all the money you began with.
To get a realistic chance of a profit, a player may need to play for hundreds of hours, and have a very large bankroll. The odds of winning overall vary with the number of packs, the house rules and the frequency of shuffling. And there is always the risk of detection, which makes it almost impossible to play an optimal game and not be spotted. It is so hard to make money from counting that casinos will often make more money from inexperienced counters than they will from a player simply playing optimal strategy from hand to hand.
How much money did the MIT teams make?
There are so many different teams, many operating since the 1980s, that exact values are hard to find. The money was split many ways, and much of it had to go back to the original investors. Also, many of the teams eventually lost all their winnings in streaks of bad luck, triggering them to split up.
So the amount each player earned depended on how long they stayed in the team. Andy Bloch estimates the Amphibians and Reptiles (the team which also formed from Strategic Investments) each made around $1m in their most successful years during the mid-90s.
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