Friday night Cross-IMP scoring
For many years the Young Chelsea has scored its Friday night game in IMPS
according to the Butler scoring method. Your score on any particular board
is compared with a 'datum', which is established by discarding the top and
bottom one or two scores achieved across the field on the board and averaging
the remaining scores. The difference between your score and the datum is
converted to IMPs plus or minus according to the normal scale.
With the widespread use of computers in scoring bridge events, the Butler
method has largely been superceded by Cross-IMPs in serious competitions.
For Cross-IMP scoring, each score is compared with every other score on
the same board – you score-up in IMPs with every other result achieved
on the board, and then take the average of all those IMP scores. This has
the advantage of not discarding any valid scores to achieve the result,
and fortunately the computer does the extra work for us.
From the beginning of April 2006, we are going to change over to scoring
by Cross-IMPs on Fridays at the Young Chelsea. This change in the form of
scoring will have no effect on your tactics. Your strategy should be as
before, to use teams rather than pairs tactics - making sure you bid your
games and slams, securing your contract rather than worrying about overtricks,
and avoiding conceding large penalties.