[helene_t]

In a pairs event, each round normally consists of some 3 or 4 boards against the same opps. This gives less statistical power than one-board rounds but has obvious logistic advantages (allthough you can have one-board rounds in large unclocked online events).

But suppose you have four tables (with duplicated boards) and four boards per round. My idea is that instead of having an NS pair and an EW pair at each table, you have an A pair and a B pair, and the A pairs sit as follows:
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........T1 T2 T3 T4
Board 1 NS NS NS NS
Board 2 NS NS EW EW
Board 3 NS EW NS EW
Board 4 NS EW EW NS
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The advantage of this design is that at each table you can compare the total matchpoints for the round between pair A and pair B, since the "looser" cannot say that they had the bad luck of being compared to the stronger pairs at the other tables.

There are some disadvantages of this design.
1) The number of boards per round must equal the number of tables - impractical except for very small events.
2) The number of tables must be a power of two.
3) If the number of rounds is smaller than (#pairs -1) you can have the bad luck of playing more often against strong pairs.

As for 1) and 2), it would have to be investigated how severe the consequences would be of some quasi-optimal design that must be chosen under more general conditions.

As for 3), the design will probably not be optimal if the aim is to have maximum statistical power for all pairwise comparisons across the whole event. But in a Swiss/survivor event, the power must be maiximal for each round.

One type of event that I have in mind is a pairs knock-out. Suppose you have 32 pairs. You play one round of 16 boards. At each table, one pair goes through to the next round.

I think this would be a pretty cool kind of event, combining the best from from pairs events:
- High statistical power (in teams matches, BAM is somewhat random while IMPs has low power because more IMPs are at stake in slam boards than in partscore boards).
- You only need to look for a partner, not for a whole team

.... with the best from knock-out team matches:
- You simply strugle against the opps at your own table: it's exiting, it's easy to understand for the audience, and there can be no motivation to loose to your friends (the rumors at the last pairs world cup comes to mind).