Hi Huw and Ralph,
Thanks for all your ideas. To make things more complicated, our
scoring goes through two steps: first we calculate the standard
corrected time on the basis of the Portsmouth Yardstick to allow
Standard, Radial and 4.7 Lasers to compete in the same fleet; after
that we apply the PH on the corrected boat times to get the final
positions. Obviously, the system has a flaw in that Radials and 4.7
should be wind indexed, as their relative performance changes
according to wind conditions, but we ignore that, and it still gives
very reasonable results.
For our system to work in Sailwave we would need a boat rating and a
PH rating which work together as described above. I am new to
Sailwave, so I may have missed something, but so far I have not
managed to multiply two ratings with each other to get the required
result. What I have tried is to use the default rating in Sailwave
to put the boat rating in but therafter I got stuck in trying to
apply the PH on the corrected boat times through the wind index
ratings field. Obviously I use these fields not for the purpose they
were created, and therefore it did not work. But while trying all
this I thought it would have been helpful if Sailwave had a boat/rig
rating field, which can be set not at competitor level but at
boat/rig level which carries a boat rating automatically to the boat
rating field when you enter a competitor's boat/rig. If this already
exists I would be very happy to be educated how it works.
My next question is how the PH dialogue box works. I have not
managed to get a formula in there without receiving an error
message, so I must be doing something wrong. And is it possible to
use the PH rating on top of a boat rating, or is it either one or
the other? And another question especially aimed at Huw: we
recalculate PH on the basis of the last 12 races. Our small events
consist of 3 races on one day, so we combine the back calculated
handicaps of a number of events to get a new PH for all club
members. How can I tell sailwave to go back to other events and pick
BCR(H)for each individual club member and calculate an average out
of that?
Maybe my questions are a bit too focused on our system, and if there
are better ways to deal with PH I would love to hear about them.
What I thought was interesting is your view about keeping the best
guys at the top. For us the best guys know very well how good they
are, and need very little encouragement to continue sailing. In
addition, our results always show the boat performance before PH,
and about 50% of our events are sailed on boat performance only, so
there is ample opportunity for the good guys to get on the prize
giving platform. For us, the PH is developed mainly to keep the
slower competitors in the fleet, and they are greatly encouraged by
winning once in a while a handicap event.
About cutting out the top and bottom performers. We only do that if
we have complete outlayers, but that happens only once or twice a
year (meaning once or twice in 40-50 events; in Uganda we sail 52
weeks a year!), usually during exceptional weather conditions: the
wind dropping, an extreme shift or a short storm. In addition, we
put an 8 point cap on back calculated handicaps, which compensates
for an unusual, mostly weak, performance which would otherwise mess
up the PH of a clubmember for a month or more. Interestingly enough,
the BCH fluctuations are very minor for the more established
sailors, generally around 1-3 points off their average. You find
bigger fluctuations with beginners, since their performance is more
erratic, although that smoothens out in a year or two, and
thereafter starts to stabilise around their level.
Lastly, we also do all our calculations on an automated spreadsheet
that works well, but sailwave looks so attractive ....
How do we take this discussion forward?
reint bakema
sailing secretary
www.sailuganda.com
Hi Reint & Ralph,
Colin has in his development plan enhancements to calculations of
achieved
handicap in a race. This will include flexibility, more as Colin's
thought
process develops, to define the mechanism's to calculate things
such as
Personal Handicaps (PH). Colin knows I am keen to see the
possibility to
calculate the handicaps according to the RYA YR2 Portsmouth
Yardstick
Scheme, which I think should be possible (but I am not a
programmer) so that
different mechanisms such as the RYA, US Sailing or Victorian YC
schemes
could be accommodated as well as individual club requirements.
I developed an Excel spreadsheet that calculated handicap values
from race
results according to the principles of the RYA YR2 scheme, which
allowed me
to vary what range of boats in the race were included in the
calculations of
Standard Corrected Time; for example if I entered 0% as the value
to
excluded at the head of the race and 66.66% for the bottom
performers in a
race I will get answers to the RYA YR2 method, but by changing the
percentage at the top to 10% and 25% at the bottom I roughly get
the middle
performing 2/3rds of the fleet racing (i.e. I am excluding the top
10%
performing boats and the bottom 25% worst perfuming boats in
race). So my
method is slightly different to Ralph's but addressing the same
problem from
a slightly different perspective, i.e exclude the best performing
(better
sailors) and the worst perfuming sailors (not so good sailors).
The aim of all of us to provide more interest in the racing; the
good guys
have to keep right at the top of the sailing at all times and
those who are
not so good can assess their progress. One thing that proved
interesting
for the better sailors was to see how much below the published PN
they could
achieve. For example one of the sailors at my club is a previous
National &
World Champion in a single-handed trapeze boat and if I remember
correctly
in one race his assessed PN for a race was -40 off the the
published PN!
So in summary it is something in Colin's development plan but at
present it
is a manual exercise. Some clubs are using the Back Calculated
Rating that
Sailwave can do today, but I think this is based on the corrected
time of
the winning boat (Colin - correct me if I am wrong). This method of
calculating the BCR is in my view (no criticism of Colin - it is
the easiest
method to implement) can be subject to great variation week on
week,
especially if the quality of the sailors changes week by week ( as
in my
example one week we will have an ex-World Champion sailing and he
will win
by a long way and then the next couple of weeks there are out only
average
club sailors).
The BCR calculated by Sailwave can be averaged over a number of
races (user
configurable) and rolled into one of the two Rating fields for an
individual
boat - one is the default rating from the rating file(s) the other
is a
value to used from now until the next change of rating which is
stored on a
per race basis. I have not used this part of Sailwave myself, but
I would
be willing to assist you in experimentation.
That's my two cents worth for now.
Kind regards,
Huw
From: sailwave@yahoogroups.com [mailto:sailwave@yahoogroups.com]
On Behalf
Of Ralph Tingle
Sent: 01 October 2006 11:14
To: sailwave@yahoogroups.com
Subject: RE: [sailwave] Personal handicap
Hi Reint
We have had similar success (in terms of competitor response)
with a
handicap system similar to yours.
One aspect however is your calculation of the base/average
corrected
elapsed time
The scored handicap for each race is calculated by by dividing
the elapsed
time of the individual by the average of the corrected elapsed
time of all
participants in the race
An issue which I felt relevant was that results at the back of
the fleet
could unfairly skew the average and to a lesser extent, the same
could apply
to the front of the fleet. To calculate my average, I therefore
excluded the
first & last 'n' results before calculating the average.
I also calculated the PH over a full year to make it easier for
new
sailors' handicaps to improve quicker, but longer for handicaps to
reflect
'aging' sailor performance 
Sorry this does not answer your question about Sailwave but may
be of
···
--- In sailwave@yahoogroups.com, "Huw Pearce" <huw.pearce@...> wrote:
-----Original Message-----
interest to you
Regards
Ralph
-------------------------------------------------------------------
---------
–
From: bakemareint [mailto:bakemareint@…]
Sent: 30 September 2006 16:13
To: sailwave@yahoogroups.com
Subject: [sailwave] Personal handicap
Hi,
I have just signed up to the Sailwave newsgroup, and would like
to
know if you have had a discussion around the topic of personal
handicaps. The reason is that we have developed a personal
handicap
system for our sailing club (Victoria Nyanza Saling Club,
Kampala,
Uganda) which has made our class racing (only Lasers and
Optimists)
very attractive to all levels of sailors. I would immediately
switch
to Sailwave for our club racing if Sailwave would be able to
accommodate our system, or something similar.
The basic principle of the VNSC personal handicap system is that
all
our club sailors are assigned every month a personal handicap
calculated as the average scored handicaps of the individual's
last 12
races. The scored handicap for each race is calculated by by
dividing
the elapsed time of the individual by the average of the
corrected
elapsed time of all participants in the race. I spare you the
details,
but the result is a very accurate rating of each club member in
terms
of his/her sailing capabilities expressed in a percentage around
the
club average of 100. So, a PH of 95 means that somebody sails 5%
faster than club average, likewise a PH of 103 means that the
person
sails 3% slower than the club average.
The VNSC PH system makes sailing attractive for all our members
to
race in handicap events, since all have about an equal chance of
winning. We update the personal handicap once a month, and the
new
list attracts a great deal of attention, as each member wants to
know
if his/her handicap went up or down and with how much.
To incorporate such a system in Sailwave requires some work, so
it
would be good to know if other Sailwave users would be
interested to
pursue this further. I am convinced that a well functioning and
fair
automated PH system would be of great use to many clubs, and
based on
our 10 years of experience with this system I believe that we
certainly have a candidate for this. If anybody is interested to
learn more about our personal handicap system, please me know,
and I
will send you more details.
Secondly, where do I go with this idea?
Reint Bakema
Sailing Secretary VNSC
www.sailuganda.com
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