John Carruthers: Bridge and Dumping

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 The Bridge World and Michael Rosenberg, in a recent article on the 40th Bermuda Bowl (in  Veldhoven last fall), bring up the possibility of yet more dumping scenarios in round robins. First, though, a little background. In all world championships which  qualify eight teams for knockout play nowadays, the team finishing first chooses its opponent from among the fifth-through-eighth group; then the second-place team chooses among the remaining three teams and third chooses between the other two. In effect, this means that the fourth-placed team will always play the perceived-best team in this 5-8 group. This seems to punish, rather than reward, a moderately-high round robin finish.

Dumping could occur in at least two scenarios in the ‘battle’ for fourth place:

(a.) A team comfortably in fourth place with a match to go would much rather play any team in the top three rather than the team in the 5-8 group it ‘knows’ will not be picked by any of the top three; additionally, if it loses fourth place to a perceivedweaker team, it might actually get to play that team in the quarterfinals if it itself is not picked by any of the top three.

(b.) A team comfortably in first place might look at the standings with a round to go and would like to play the currently fourth-placed team – they are, however, playing their last match against a very strong fifth-place team, a team they consider to be their main rivals in the event. It is not too difficult to imagine the firdt-place team losing to the fifth-place team, elevating them to fourth place to enable the quarterfinal match the first-place team desires. “We’ll worry about carryover later,” they think.

We are certain that more Machiavellian minds than ours can come up with even more possibilities. In any case, there were no issues in this Bermuda Bowl. Somewhat ameliorating the possibility of dumping is the fact of carry-forward – the WBF uses the head-to-head match to determine carryover – one-half or one-third of the match margin (to a maximum, depending on the length of the match to be played). Against that is the length of the knockout matches, reducing the effect of carryover. There are solutions to this issue (did you guess?) and the WBF would do well to look at the situation before it becomes a problem.

(i.) The NEC tournament in Yokohama each February has adopted the simplest solution of all: the first-, second- and third-ranked teams may choose among the fourth-througheighth place finishers rather than the WBF method of choosing among fifth through eighth. Thus, they have eliminated the possibility that finishing eighth is markedlybetter than finishing fourth. Essentially, fourth through eighth are equivalent (except that, in the NEC version of carry-forward, the JCBL awards ½ IMP to the higherfinishing round robin team – no draws in regulation time!).  

(ii.) Make finishing fourth a prize by allowing the team finishing fourth to reject whether it allows the first through third teams to pick it – it can choose (a.) to be lumped in with either the first-through-third group, taking its chances on an opponent from five through eight, or (b.) to be grouped with the fifth-through-eighth teams, allowing itself to be picked by one, two or three.

 (iii.) Allow the fourth place team to choose its semifinal bracket grouping. As it stands now, the team finishing first in the round robin, after the quarterfinal matches are set, chooses which of those matches it has it its semifinal bracket. Giving this right to the fourth-placed team would make trying for fourth worthwhile, but not quite as worthwhile as picking a quarterfinal opponent. Whatever is done, we must make it more worthwhile to finish fourth than eighth. Currently, it is not.

John Carruthers

 (IBPA Bulletin June 2012)

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