[awm]

All of these events have different advantages and disadvantages. For example:

Bracketed knockouts
Pros: You get to play long matches, which reduces the inherent randomness of IMP events. If the bracketing is reasonably accurate then you get to play against teams of comparable level, meaning that you will be challenged but you also have a chance to win. You can play essentially at your own pace, rather than having tightly clocked rounds as in a pairs game. If at some point you're out of contention you can quit the event (in fact, this will be done for you).
Cons: It's hard to "play up" which can be a good experience. This also reduces the ability of mediocre players to encounter world champions at the table (one of the things supposedly great about bridge). If the bracketing is inaccurate it can be frustrating for people who are placed in the wrong field.

Swiss events
Pros: You're not forced into a bracket and get to potentially play against everyone. However, you still get to play a reasonable percentage of matches against teams of comparable level (assuming teams perform as their level would imply). A lot of teams will be within striking distance of winning the event even in late rounds, so you almost always have a "chance to win" (or at least place in the overalls) until near the end if you can just blitz your last couple matches.
Cons: With lots of short matches, the event can be fairly random, even worse if using shuffled boards for swiss teams like in ACBL. There is a fair amount of luck in the draw as well, because different teams will play against very different strength of field. The ability of teams to stay within striking distance can also be frustrating, as a team which is leading going into the last round can beat a tough opponent by a small margin and still end up in second or third.

Pairs movement events
Pros: You get to play against almost everyone in the event, which is fun and equalizes strength of field. The event is less random than many other formats of comparable length (especially with matchpoint scoring). You're playing the same boards as everyone else, which also reduces the luck factor compared to swiss or even knockout events with shuffled boards.
Cons: You have to play against almost everyone in the event, including pairs which are much worse or much better than you are. If the field includes a lot of weak pairs, the event often degenerates into "who can best beat down the bad players" which is not exactly luck but arguably not a true test of bridge skill either. The timed aspect can be annoying, since everyone must be kept synchronized there is often a lot of waiting between rounds for the fast pairs (and a lot of "hurry up" from the director for the slow pairs).

[awm]

Perhaps another interesting observation is that swiss teams tend to favor pro teams.

Say you have a team of six, and your team is fairly average when the sponsor plays but one of the best teams when he sits out. Because of the way swiss is structured, if you play the sponsor for the first half of the matches you will not fall too far behind the leaders, since once you are behind you play a weaker strength of opposition.

Then for the second half, you're behind but not too far back, and you're playing a relatively weak opponent with your best lineup. Blitz them and you're back among the contenders (most of whom were playing stronger opposition).

In comparison, for a round robin event your score is more correlated to the "average strength" of your team rather than to the "strength of your team for a small number of critical matches at the end." A team that is weaker than the four-pros lineup but stronger than the pro team "on average" will probably finish ahead.

[nige1]

Siegmund, on Feb 28 2010, 12:23 AM, said:

Aaaah! We have a Loki worshipper in our midst.

God's order: a perfect seeding order. I was trying to avoid quibbles about anomalies like "Team A usually beats Team B usually beats Team C usually beats Team A". Unfortunately I triggered the usual put-downs. Sorry.

Suppose 64 teams enter a competition and each team has time to play about 65 boards. Among the organizer's options are:

• Round-robin: 63 x 1-board matches between each pair of teams. Lots of comparisons but they seem too short.
  
  
• Knockout: 6 x 11-board knock-out rounds, sending half the field home at each stage. Even were there no luck involved, the second best team could be eliminated on the first round.
  
  
• Double-elimination is a Knock-out, where you must be defeated twice to be eliminated. Many players think these are fairer than straight Knock-outs.
  
  
• Swiss: 8 x 8-board rounds. A gradual sieve with twice as many comparisons as a knockout.

A Swiss takes the Double-elimination idea to its logical conclusion. Hence, IMO, in typical circumstances, with limited time available, a Swiss is more effective than a knock-out or round-robin. This argument applies to both teams and pairs competition. I concede, that if you have unlimited time, a round-robin might be better.

A simulation might convince me that I'm wrong.

FrancesHinden, on Feb 27 2010, 02:06 PM, said:

You need to remember that there have to be events in which the little guys can enjoy themselves and hope to win, or there will be no events at all.

We do enjoy Swiss competition, even when we don't win.

[phil_20686]

Actually I really like swiss pairs events. They have a number of advantages.

1) If you have a bad session you are not necessarily out of the running. As a junior with a fairly demainding phd and no car the comination of being tired on a friday evening, or being hunover for at least one morning, pretty much insures that I will have a bad session. Thus for national pairs events that are part social event and part serious bridge swiss makes a happy comprimise.

2)In a swiss pairs it is neither necessary nor desirable to score the MP scores across teh whole field. In brighton they run a 14 round swiss pairs with 7 (or is it eight?) board matches, but they score it by room, so in the top 25 tables you are only scoring up vs the other top 25 tables. This is one of the huge plus factors. This somewhat compensates for the huge plus factor you normally get from holding the points and declaring in whole field events.

3)Getting to play long(ish) matches against top pairs is really what bridge is all about.

4)The randomness argument doesnt really seem to hold up that much. As long as you keep playing well you will keep grinding out a reasonable number of VP's per match. Its true that on a given set of boards a good pair playing against you might just do the right thing and give you a bad score, but thats just bridge. It happens in every form of scoring.