Bridge - Game Strategy
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Game strategy
Bidding
Much of the complexity in bridge arises from the difficulty of arriving at a good final contract in the auction. This is a difficult problem: the two players in a partnership must try to communicate sufficient information about their hands to arrive at a makeable contract, but the information they can exchange is restricted—information may only be passed by the calls made and later by the cards played, not by other means; in addition, the agreed-upon meaning of all information passed must be available to the opponents.
Since a partnership who has freedom to bid gradually at leisure can exchange more information, and a partnership who can interfere with their opponents' bidding (or who raise the bidding level rapidly) can cause difficulties for their opponents, bidding systems are both informational and strategic. It is this mixture of information exchange and evaluation, deduction, and tactics that is at the heart of bidding in bridge.
Bidding systems and conventions
A bidding system is a set of partnership agreements on the meanings of bids: each player evaluates their hand and their best tactics, in light of new information, and makes bids to give or request information from their partner with the goal of arriving at an ideal contract. A partnership's bidding system is usually made up of a core system, modified and complemented by specific conventions (optional customizations incorporated into the main system for handling specific bidding situations) which are pre-chosen between the partners prior to playing. The line between a well-known convention and a part of a system is not always clear-cut: some bidding systems include specified conventions by default. Bidding systems can be divided into mainly natural systems such as Acol and Standard American, and mainly artificial systems such as the Precision Club.
Bids are usually considered to be either natural or conventional (artificial). A natural bid is one where the suit and level bid is essentially passing the information "I have this suit for you", or in the case of a double "I want to raise the stakes as I don't think the opponents can make their contract". By contrast, a conventional (artificial) bid offers and/or asks for information by means of pre-agreed coded interpretations, in which some bids convey very specific information or requests which are not part of the natural meaning of the bid. Thus in response to 4NT, a 'natural' bid of 5Template:Ds would state a preference towards a diamond suit or a desire to play the contract in 5 diamonds, whereas if the partners agree to use the common Blackwood convention, a bid of 5Template:Ds in this situation says nothing about the diamond suit, but tells the partner that the hand in question contains exactly one ace.
Conventions are valuable in bridge because of the need to pass information beyond the simple like or dislike of a named suit, and because the limited bidding space can be used more efficiently by taking situations where a given bid will have less utility and giving that bid an artificial meaning that conveys more useful information. There are a very large number of conventions that players often choose from. Well-known conventions include Stayman (to ask for the show of any 4 card major suit in a 1NT opening hand) and Blackwood convention (to ask for information on aces and kings in a slam bidding situation).
The term preempt refers to a high level tactical bid by a weak hand, relying upon a long suit rather than high value cards for tricks. Pre-emptive bids serve a double purpose—they allow a player to indicate they are bidding on the basis of a long suit in an otherwise weak hand, which is important information to share, and also effectively raises the stakes before a possibly strong opposition can identify whether they have a good possibility to play the hand. Several systems include bids on weak hands with 6 or 7 card suits at the 2, 3 or even 4 level, as preempts.
Basic natural systems
As a rule, a natural suit bid indicates a holding or at least 4 (or more depending on the system) cards in that suit as an opening bid, or a lesser number when supporting partner; a natural NT bid indicates a balanced hand.
Most systems use a count of high card points as the basic evaluation of the strength of a hand, refining this by reference to shape and distribution if appropriate. Aces are counted as 4 points, kings as 3, queens as 2, and jacks as 1 point; therefore, the deck contains 40 points. In addition, the distribution of the cards in a hand into suits may also contribute to the strength of a hand and be counted as distribution points. A better than average hand, containing 12 or 13 points, is usually considered sufficient to open the bidding, i.e. make the first bid in the auction. A combination of two such hands (i.e. 25 or 26 points shared between partners is often sufficient for a partnership to bid, and generally make, game in no trumps; more may be needed for a suit game).
In natural systems, 1NT opening bid usually reflects a hand that has a relatively balanced shape (usually between 2 and 4 cards in each suit) and a limited number of high card points, somewhere between 12 and 18 (normally a 3 point range e.g. 12-14, 15-17 or 16-18).
Opening bids of 3 or higher are preemptive (tactic) bids, i.e. bids made with weak hands that especially favor a particular suit, opened at a high level in order to frustrate the opposition. A hand of Template:BridgeHandInline would be an ideal candidate for an opening bid of 3Template:Ss, designed to make it difficult for the opposing team to bid and find their optimum contract even if they have the bulk of the points.
Openings at the 2 level may be unusually strong (2NT, natural, and 2C, artificial) or preemptive depending on the system. Unusually strong bids communicate an especially high number of points (normally 20 or more) or a high trick taking potential (normally 8 or more).
Opening bids at the one level are made with hands containing 12/13 points or more which are not suitable for one of the preceding bids - with some systems (e.g. Standard American or 5-card majors) a major suit opening shows a 5-card suit (5-card major treatment, in which an opening bid of 1Template:Hs or 1Template:Ss promises at least 5 cards in that suit. This leads to some awkward bids, for instance, when a player has four cards in each major, and is forced to open the bidding with 1 of a 3-card minor suit).
Doubles are sometimes used in bidding conventions. A natural, or penalty double, is one used to try to gain extra points when the defenders are confident of setting (defeating) the contract. The most common example of a conventional double is the takeout double of a low-level suit bid, implying support for the unbid suits and asking partner to choose one of them.
Variations on the basic themes
Bidding systems depart from these basic ideas in varying degrees. Standard American, for instance, is a collection of conventions designed to bolster the accuracy and power of these basic ideas, while Precision Club is a highly conventional system that uses the 1Template:Cs opening bid for strong hands (but sets the threshold rather lower than most other systems) and requires many other changes in order to handle other situations. Many experts today use a system called 2/1 game forcing. In the UK, Acol is the standard system. There are even a variety of techniques used for hand evaluation. The most basic is the Milton Work point count, but this is sometimes augmented by other guidelines such as losing trick count, law of total tricks or Zar Points.
Play techniques
Terence Reese, a prolific author of bridge books, points out that there are only four ways of taking a trick by force, and two of these are very easy:
- playing a high card that no one else can beat
- trumping an opponent's high card
- establishing long suits (the last cards of which will take tricks if the opponents don't have the suit and are unable to trump)
- playing for the opponents' high cards to be in a particular position (if their ace is to the right of your king, your king may be able to take a trick)
Nearly all trick-taking techniques in bridge can be reduced to one of these four methods.
The optimum play of the cards can require much thought and experience. However, some basic ideas of probability may be considered:
Some of the most important probabilities have to do with the position of high cards.
- The probability that a given opponent holds one particular card, e.g. the king: 50%
- The probability that a given opponent holds two particular cards, e.g. the king and the queen: approximately 25%
- The probability that a given opponent holds at least one of two particular cards, e.g. the king or the queen: approximately 75%
When developing long suits, it is important to know the likelihood that the opponents' cards in the suit are evenly divided between them. Generally speaking, if they hold an even number of cards, they are unlikely to be exactly divided; if the opponents have an odd number in the suit, the cards will probably be divided as evenly as possible. For example, if declarer and dummy have eight trumps between them, the opponents' trumps are probably (68% chance) divided 3-2 (one opponent with three trumps, the other with two) and trumps can be drawn in three rounds. If declarer is trying to play with a seven card trump suit, it is more likely that the outstanding trumps are divided 4-2 (48%) than that the cards are evenly divided 3-3 between the opponents (36%).
Basic techniques by declarer
- trumping
- crossruff
- establishing long suits
- finesse
- managing entries
- drawing trumps
Advanced techniques by declarer
- counting the hand (tracking the distribution of suits and high cards in the opponents' hands using inferences from the bidding and play)
- coup
- duck
- dummy reversal
- endplay
- principle of restricted choice
- suit combinations
- safety play
- squeeze
Basic techniques by defenders
- opening lead
- when to lead trump
Advanced techniques by defenders
- avoiding an endplay or squeeze
- counting the hand (tracking the distribution of suits and high cards in the unseen hands using inferences from the bidding and play)
- false carding
- opening lead—using information from auction
- Signal (bridge)|signaling
- uppercut (bridge)|uppercut
Computer bridge
After many years of little progress, at the end of the twentieth century computer bridge made big strides forward. In 1996, the American Contract Bridge League (ACBL) initiated official World Championships Computer Bridge, to be held annually along with a major bridge event. The first Computer Bridge Championship took place in 1997 at the North American Bridge Championships in Albuquerque, New Mexico.
Strong bridge playing programs such as Jack (World Champion computer bridge 2001, 2002, 2003, 2004, 2006) and Wbridge5 (World Champion computer bridge 2005) probably rank among the top few thousand human pairs worldwide. A series of articles published in 2005 and 2006 in the Dutch bridge magazine IMP describes matches between Jack and seven top Dutch pairs. A total of 196 boards were played. Overall, the program Jack lost, but with a small margin (359 versus 385 imps).
Bridge on the Internet
There are several free and some subscription-based servers available for playing bridge on the Internet.
- OKbridge [1] is the oldest of the still-running Internet Bridge services; players of all standards, from beginners to world champions may be found playing there.
- SWAN Games [2] is a more recent competitor.
- Bridge Base Online [3] is the biggest online bridge club in the world, and provides the largest variety of services and games for free.
Some national contract bridge organizations now offer online bridge play to their members including the English Bridge Union, the Dutch Bridge Union and the Australian Bridge Federation. MSN and Yahoo! Games have several online rubber bridge rooms. In 2001, World Bridge Federation has issued a special edition of the lawbook adapted for internet and other electronic forms of the game.
Advantages of playing bridge online are:
- Flexible choice of when to play.
- Choice of opponent skill level.
- Player rating system that attempts to measure ability without regard to the number of games played or the number of years spent accumulating masterpoints
- Fewer restrictions on which conventions can be used.
- Unauthorised information cannot be passsed by tone of voice or body language.
- Detailed records may be kept, to help resolve complaints.
- The software prevents plays and calls that are against the laws.
Disadvantage are:
- A greatly reduced social element.
- Increased opportunities to cheat, using Instant Messaging technology
- Players dropping out after a few hands
External links
- American Contract Bridge League
- Dutch Bridge Bond
- English Bridge Union
- Laws of Contract Bridge
- United States Bridge Federation
- World Bridge Federation
History of bridge
- Bridge and Auction Bridge, "Valet de Pique". 1912 London, Eveleigh Nash.
- Bridge Whist, C.J.Melrose. 1901 London, L Upcott Gill and New York Charles Scribner's Sons.
- Elwell's Advanced Bridge, J.B.Elwell. 1905 (5th ed) London, George Newnes.
- Foster's Whist Manual, R. F. Foster. 1899 (4th ed) London, Frederick Warne and Co with Mudie and Sons
- Royal Auction Bridge, Ernest Bergholt. 1915? London, George Routledge & Sons.
- The Bridge Manual, "John Doe" (George Cavendish Benedict). 1900 London, Mudie and Sons.
