I meant to comment on this back when it first went out but never got
around to it.
The BCR generated by Sailwave is helpful but probably shouldn't be used
for handicapping purposes. Sailboat race results tend to be somewhat
bell-shaped with a distinct tail toward the slow end. Accordingly, the
best way to come up with "personal handicaps" would be by comparison to
the middle (median) finisher in a race. That way the "typical" fleet
handicap should stay close to the Portsmouth or other handicap number -
with some being faster and some being slower.
If you were to use the BCR generated by Sailwave, over time ALL of the
fleet handicaps would be slower than a standard handicap. [Think about
it - after the 1st race everyone will be rated slower than standard
except the winner and if someone else wins the 2nd race then everyone
will be rated slower than someone who is rated slower than standard,
etc.] The result will be that a new skipper in the fleet would start out
at a significant disadvantage since everyone else will be rated slower
than standard and the new skipper will be rated standard. Also, those
who do more races would have their personal handicaps moved slower at an
accelerated rate.
Since you are going to have to do some kind of spreadsheet analysis
anyway, I would do PLUS and MINUS from the middle boat (with the middle
two boats being averaged if you have an even number of boats). You could
use the BCR or the elpased time (in seconds/mile) as the reference
point, it doesn't really matter. You just don't want to use the BCR
without some further processing.
Art
There isn't a simple way to do this with Sailwave, but it can be done.
For handicap races, Sailwave can show the factor BCR - Back Calculated
Rating. Art Engel prefers to call this Rating to Win. Its the handicap a
sailor would need in order to get the same corrected time as the race
winner. Show this either on screen via View / Show Result Cells As / BCR
or Publish / Individual Race Tables with BCR added as an additional
column.
If you average this factor for a skipper over a number of races
(possibly excluding some unusually good or bad races), a factor can be
arrived at that can be used as a Personal Handicap.
regards,
Malcolm Osborne
Sedgefield, South Africa
From: nicholas.zervos
To: sailwave@yahoogroups.com
Sent: Monday, May 04, 2009 4:33 PM
Subject: [sailwave] personal handicaps
Dar es Salaam Yacht Club in Tanzania use Sailwave for our results
we have about 20 boats each race H16s Tigers Nacras etc and about 36
active racing cats
we use boat class ratings but i would like also to introduce
personal handicaps for each boat based on performance - like a golf
handicap system
i would like to calculate the adjusted personal handicaps for each
boat based on the first 3 months results 2009 - use those for the next
quarter - then readjust each quarter etc - and then have annual results
maybe there is a code in Sailwave that does this - or you know of a
simple way for me to do this?
···
--- In sailwave@yahoogroups.com, "Malcolm Osborne" <malcolmo@...> wrote:
----- Original Message -----
would appreciate any guidance
regards - nick