Matchpoint Strategy

This is just meant an an introduction to the topic as it relates to the difference between matchpoints (MP) and IMPs, and how these difference can effect both the bidding and play.

At imps, the strategy can be summarized pretty simply as stretch to bid any vulnerable game that has almost any chance to make, and (almost) always play to make your contract, taking the safest line of play available (at imps doubled, you might decide to play safely for down one rahter than risk down four or five, but that is an exception).

This "stretch" to bid vulnerable games means you will bid games with less than 50% to make. How much less? Roughly 1 in 3. This is related to the scoring table at imps. A vul game (lets say 4S) is worth 620, while if you bid a part-score you get 170. The difference, 450, is worth 10 imps. But if you bid the partscore and the game goes down one, the result would be -100 versus 140, or a 240 imp difference, which is 6 imps. So you win 10 imps when right and lose 6 imps when wrong. So if the game has ~37.5% chance of making, you break even (in the long run) by bidding it.

Unlike IMPs where the size of the score is important (which is why you bid close games), at MP you win a single matchpoint for each pair you beat, and 1/2 a point for each pair you tie. NOTE: At imps the size of the difference between you and the opponent is important, but at MP, you win or lose 1 point depending on whether you scored more or less than your opponent, the SIZE of the difference at MP is irrelevant (who said size matters)?

At MP, this results in an oddity: beating someone by 2300 points or 10 points on a hand is worth exactly the same (1 MP). This wining by 10 points, the diffence between 1N making one and 1S making one, or 7S making or 7NT making, is worth the same MP if you are on the plus side as if 7Sxx went down 13 while you made 7NT. This oddity, that size of the differences doesn't matter which makes Matchpoint strategy very different from imp strategy. For example, people play in NT more ofter at matchpoint than imps (NT scores more), people seldom play 5C or 5D at matchpoint, prefering riskier 3NT or 4M on 4-3 fit, as they score more (if they make).