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Basic Instinct

A brief look at the psychology of blackjack

Playing blackjack is relatively straightforward. Most of us played variations like ‘21’ and ‘pontoon’ as children. In the casino, all a player has to do is make a bet before a card is dealt and decide whether to ‘hit’ or ‘stand’ on the total. Simple. However, as with the psychology of all great games, the rules are easy enough for almost anyone to play but can take a lifetime to master.

One of the main reasons that blackjack attracts regular gamblers is that it is a game that the skilful player can expect a profit in the long run. It is the only game that casinos offer where the chances of winning favour the gambler. A gambler’s playing strategy is dictated by how they can influence the outcome simply by taking or avoiding extra cards. Research into the psychological strategies of blackjack playing have shown that gamblers fall into one of three main types. Firstly, there is the ultra-conservative 'never bust' approach where the gambler sticks on any hand that could go bust on the next card (i.e., any hand of 12 and over). Since the dealer must draw until they reach 16, this approach will certainly pay off some of the time. A second popular strategy is ‘mimic the dealer’ where gamblers sit on 17 or more but draw to 16 or less. The psychology here is that if it’s good for the dealer it must be good for the gambler. However, very few regular players will follow either of these simplistic strategies.

Most gamblers adopt optimum 'basic' strategies in which the decision to hit or stand depends on the ‘up-card’ held by the dealer. The player knows that as the game progresses, the number of cards left in the shoe is limited. If a player keeps count of the ratio of 10 value cards to non-10 value cards they can place minimum bets when the deck is favourable to the gambler and maximum bets when the ratio is favourable. The smaller the ratio, the richer the deck is with 10 value cards and the greater the advantage to the gambler. This well known card counting method was first laid out over 40 years ago by the mathematician Ed Thorp in his classic 1966 book Beat The Dealer.

Some people have said that the book stands in relation to gambling as Einstein’s theory of relativity does to physics—it changed perception of reality! More elaborate counting methods are available based on awarding points to low, medium and high cards and by keeping a running count of unseen cards. Over the years, many people have used elaborate systems in order to keep count.

The reaction of the casinos to card counting has been predictable. Many in the gaming industry view card counting as cheating and will ask players to leave the casino. Many casinos use up to eight packs of cards in the shoe to make counting hard. In casinos where only one or two decks are used, the cards are constantly reshuffled. Some casinos even teach the dealers how to card count so that they will only reshuffle when the odds are favouring the gambler. What’s more, the casinos find card counters easy to spot. They will make minimum bets on most hands and then occasionally make very large bets to take advantage of favourable decks. Therefore, really good counters must also be able to ‘camouflage’ their counting methods by being more variable in their betting strategy.

The good news for card counters is that most casinos prefer smaller decks so that more games can be played per hour (which means more money for the casino). Most casinos know that card counting gamblers may lose count or patience. Furthermore, some gamblers are competent in the short term but may crack under pressure with the long hours needed to make a consistent profit. It is estimated that one out of 20,000 players is a genuine counter and of these only one in twenty is a winner.

Research has been carried out into the most common errors that blackjack players make while gambling. One of the most well known was a study carried out in Holland by the psychologists Dr Gideon Keren and Professor Willem Wagenaar on 112 regular blackjack players (and published in the Journal of Experimental Psychology). Wagennar showed that 44% of playing errors involved not taking an extra card when they should have and that 16% of errors involved taking an extra card when they shouldn’t have. They also found that the error rates were related to the value of the dealer’s up-card. When the players should have stood they were less likely to do so when the dealer’s up-card had a low value. Where they should have taken an extra card, they were also less likely to do so if the dealer’s up-card had a low value. Keren and Wagennaar also showed that players exhibited poor insurance strategies when the dealer’s up-card was an ace. These findings clearly show that most gamblers play conservatively in an attempt to stay in the game. They stand when extra cards should be taken, do not double up when they should do, and take out insurance unnecessarily.

References

Nicholas A. Bond (1974). Basic strategy and expectation in casino Blackjack. Organizational Behavior and Human Performance, 12, 413-428.

Keren, G.B. & Wagenaar, W.A. (1985). On the psychology of playing blackjack: Normative and descriptive considerations with implications for decision theory. Journal of Experimental Psychology: General, 114, 133-158.

Thorp, E.O. (1966). Beat the Dealer: A Winning Strategy for the Game of Twenty-One. New York: Random House.

Wagenaar, W. (1988). Paradoxes of gambling behaviour. London: Erlbaum.

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