When will playing Rubber Bridge vs. Duplicate Bridge affect your decisions?

Question

In Rubber Bridge, you are trying to get more points than your opponents. In Duplicate Bridge, you are trying to get more points than the other people playing the same hand later on do. For a while I thought this wouldn't make a difference, but then I've noticed bridge columns occasionally offering different suggestions depending on which is being played, and couldn't make sense of it, because in either situation you're goal is to get as many points as possible.

When would you make a different decision based on if you were playing Rubber vs. Duplicate Bridge? How are the strategies different for them? After looking at a complete record of the decisions players made in a bridge hand, how can I tell if it was played at Duplicate or Rubber? What does it take to be good at Duplicate after you've become pretty good at Rubber?

Answer 1

I wholly agree with thesun's answer, particularly "you must squeeze every ounce of potential out of your cards". But since you've posed particular queries at the end of your question:

Part-scores are the most obvious difference. If you have strong Hearts, but not strong enough for slam, a Rubber player looks at the scoresheet; with 60 points below the line, there is no point going above 2H unless forced (overtricks score the same as bid tricks, and there is no risk of failure). A Duplicate player knows there is no line: bid to 4H if you can make it. Similarly with honours: a marginal hand with KQJT, worth bidding at Rubber because of the cushion 100 honours will give, is not worth bidding at Duplicate.

Strategy: again, Rubber bridge is about making the best of your situation, while Duplicate is about making the best of your cards, Take sacrifices: a Duplicate player knows that if he goes one down doubled but stops opponents making a game, he has done well out of that hand. At Rubber bridge, you have saved the rubber for now, but if the opponents win a few hands later, all your sacrifice achieved was to cost you a few hundred points. More generally, if by strategy you mean scoring as many points as possible (as I think you should), any change in the scoring method will affect your strategy.

Usually, you can't tell under which system a particular hand was played; obviously, if one side started with 30 below the line it was at Rubber, and if two declarers took different routes it was Duplicate.

And if you are really a good Rubber bridge player, you will be (or are) a good Duplicate player. 'Good', of course, is compared to 20 or 30 others, rather than 3, and you may find that your system is too ill-defined to be acceptable without work: but it's the same game, and just as enjoyable if not more so.

Answer 2

This is a pretty large topic and you could easily write an essay, or indeed a book, on the subject! As a starting point I would recommend the Duplicate Bridge wikipedia page, with particular reference to the "Scoring and tactics" session. Take especial note of the differences that arise if you're playing Matchpoint or IMP scoring.

Really, Duplicate and Rubber bridge are the same game - it's just that different results are weighted differently for scoring purposes. In rubber bridge, you can get away with bidding quite conservatively - slow and steady can usually win the race. In duplicate, you must squeeze every last ounce of potential out of your cards, making it a more rigorous, competitive, high-stakes form of the game. And some would say more fun, if your heart can take the strain!

Answer 3

In the bidding: in rubber bridge you should be more aggressive bidding games, as the 300 or 500 bonus makes a good bet bidding games making 30-40% of the time. Playing MPs you shouldn't settle for games making less that 50% (frequency is the name of the game).

In the card play: playing duplicate, overtricks are specially relevant when you are playing a normal contract (3NT+2 vs 3NT+1 may be the difference between an 80% and a 20% in a given board), in rubber bridge the converse is true: making the contract is the main goal. So its not rare to see a good player making a safety play in rubber bridge, but ignoring it (for the chance of an overtric(s)) in MPs.

Answer 4

For the most part rubber bridge plays the same as IMPS, so let us instead distinguish between matchpoints on one side, and IMPS/Rubber on the other.

The most important distinction is the basis for measuring risk and reward. As a general rule (see below for when this does not apply):

• In matchpoints, any play that stands to gain more often than not is advantageous.
• In IMPS/rubber, one must weight the risk and reward according to the stakes of each, and decide on the expected value of the point gain/loss.

As an example, it is foolishness of the highest order in IMPS/rubber to risk a contract for a 60% chance of an overtrick; in matchpoints NOT doing so is foolishness of the highest order. Likewise, safety plays are made use of much more often in IMPS/rubber than in matchpoints.

The exceptions to this rule are when:

• In matchpoints if from other information obtained, the contract is already believed to be a good one. For example: if an advanced play is required to make the contract; or an unusually favourable lead was obtained; or the contract is fortuitously played reversed due to one's bidding system; when in a hard-to-bid slam; etc.

Answer 5

In rubber bridge, you should try to get a partscore on. After getting the partscore on, slam bidding is much easier. The only time you want to sacrafise is if you have am extremely good fit against a slam, or if the opponents are taking a vulnerable rubber. Your goal is to make your contract. In IMPS, it is very similiar, trying to make your contract, but you have the game bonus and try to bid a game more often. Slam bidding isn't as easy. Sacrifices can be made if both are nonvulnerable. Your goal is to bid the safest contract and try to make it. In matchpoints, your goal is to try to take as many tricks as you can. You should avoid five of a minor games,and try for 3NT instead. 4 of a major should be bid if either of you are not 4-3-3-3. Bid level bonuses if there is at least 50 percent chance of making-be conservative at level bonuses. Stretch to compete, sacrifice often, and don't always try to make your contract. If making the contract is less than 50 percent, and if it fails means going down am extra trick, then settle for the lowest number of undertricks.