Can Sailwave Do Our Scoring?

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1

Can Sailwave Do Our Scoring?
I tried to migrate to Sailwave last year but was not able to get it to meet all of our current scoring requirements. We have 2 unique scoring requirements that I was wondering if Sailwave can handle:

  1.  Each yacht in the fleet is required to perform RO duty from time to time during any of the series.  We award the lesser of (average finish position for all completed races in the series truncated to the next smaller integer) or (number of boats starting + 1). As the series progresses, any value for RO duty could change weekly depending on how the yacht performs. I believe that Sailwave supports this via an average only, and not a truncation, and would require a manual entry for the number of boats starting +1 if that value were less than the truncated average finish position in the series.

  2.  We use a slightly modified PHRF of the Chesapeake High Points system ([http://www.phrfchesbay.com/2012hprules.pdf](http://www.phrfchesbay.com/2012hprules.pdf)) as well.  There are 3 series for Low Points (see above) but all races from each series are included in the high points.  The scoring for high points is:

[High Points (always a fraction <= 1.0)] = [Total of Points Earned* for the Year] / [(Total max points possible** if the yacht won every event in which she started) + (total number of scheduled races that are scheduled/completed {[normally 24 (8 for each series)] – [number of races that are abandoned or cancelled]})]

  • “Points Earned” are one point for starting, one point for finishing, and one point for every boat beaten.

** Total max point possible is the sum of (Number of boats starting + 2) for each race in which the boat came to the start line.

One throw-out is allowed for every 6 races. Throw-outs will be determined by the Chief Scorer to achieve the highest possible score for the yacht. Note that the highest possible score may be the result of a yacht not using all of its throw-outs.

In addition, the Chief Scorer (aka me) would like to enter the results only once.

Currently we use Excel and VBA that I developed to do our scoring, but I would like to use a supported product. This allows an easier transition to a new chief scorer in the future.

Thanks,

Tom Owen

Dahlgren Yacht Club

Dahlgren, Virginia, USA

2

Hi Tom,

Sorry for the delay. Probably not is the real answer. But I’d like to work with clubs more and satisfy them - these scoring system must crate so much fun at the bar. If you email me personally - colin@sailwave.com we can work through it if you like.

···

On Tue, Feb 19, 2013 at 9:53 PM, Tom Owen towen999@msn.com wrote:

I tried to migrate to Sailwave last year but was not able to get it to meet all of our current scoring requirements. We have 2 unique scoring requirements that I was wondering if Sailwave can handle:

  1.  Each yacht in the fleet is required to perform RO duty from time to time during any of the series.  We award the lesser of (average finish position for all completed races in the series truncated to the next smaller integer) or (number of boats starting + 1). As the series progresses, any value for RO duty could change weekly depending on how the yacht performs. I believe that Sailwave supports this via an average only, and not a truncation, and would require a manual entry for the number of boats starting +1 if that value were less than the truncated average finish position in the series.

  1.  We use a slightly modified PHRF of the Chesapeake High Points system ([http://www.phrfchesbay.com/2012hprules.pdf](http://www.phrfchesbay.com/2012hprules.pdf)) as well.  There are 3 series for Low Points (see above) but all races from each series are included in the high points.  The scoring for high points is:

[High Points (always a fraction <= 1.0)] = [Total of Points Earned* for the Year] / [(Total max points possible** if the yacht won every event in which she started) + (total number of scheduled races that are scheduled/completed {[normally 24 (8 for each series)] – [number of races that are abandoned or cancelled]})]

  • “Points Earned” are one point for starting, one point for finishing, and one point for every boat beaten.

** Total max point possible is the sum of (Number of boats starting + 2) for each race in which the boat came to the start line.

One throw-out is allowed for every 6 races. Throw-outs will be determined by the Chief Scorer to achieve the highest possible score for the yacht. Note that the highest possible score may be the result of a yacht not using all of its throw-outs.

In addition, the Chief Scorer (aka me) would like to enter the results only once.

Currently we use Excel and VBA that I developed to do our scoring, but I would like to use a supported product. This allows an easier transition to a new chief scorer in the future.

Thanks,

Tom Owen

Dahlgren Yacht Club

Dahlgren, Virginia, USA

3

Tom,

I think you might have a typo in your write-up.

If I look at the PDF you referenced from Chesapeake PHRF their formula is POINTS_EARNED/TOTAL_POINTS_POSSIBLE. I take it that is your goal. Chesapeake PHRF uses the same race points as you but they also allow "Bonus" points. So their "TOTAL_POINTS_POSSIBLE" is the total points if a boat had won every race AND the total maximum "bonus" points. You don't mention "bonus" points so perhaps you meant your formula to be

···

*****
[High Points] = [Total of Points Earned* for the Year] / [(Total max points possible** if the yacht won every event in which she started)]
*****

This is not an uncommon calculation (US Sailing recommends almost the exact same thing for a long series). See http://raceadmin.ussailing.org/Rules/Long_Series.htm . However, most folks multiple the ending fraction by 100 to come up with a whole number equal to a "winning percentage" number.

One important feature of a "percentage of perfection" scoring system isn't mentioned by you - a minimum number of races to qualify for the series. Otherwise, the boat that wins the first race should never come out again as its percentage will be 100% at the end of the series.

Your message mentioned adding the total number of races held to the denominator but I don't know why you would want to do that. A "percentage of perfection" calculation is intended (at least in theory) to give an equal chance of success to boats that do fewer races. But, by artificially increasing the denominator you penalize boats that do fewer races. That might be intentional but it goes against the basic idea of a "percentage of perfection" calculation. Plus, I think you meant

*****
(total number of scheduled races that are completed)
*****

rather than

*****
(total number of scheduled races that are scheduled/completed)] - [number of races that are abandoned or cancelled])]
*****

since the latter would seem to result in two less races counted for every race that is not run as scheduled.

THROW OUTS / DISCARDS

I cannot think of a situation where a boat would be better off with fewer discards. If a boat has all 1st-place finishes then her score will be the same (100%), not better, with fewer discards but in all other circumstances I think a boat's series score would be worse with fewer discards. A percentage of perfection system doesn't normally use discards as that goes against the very idea of the system. Plus, to determine which race scores to discard you would have to divide each individual race score by the total possible points for that race and then discard the scores with the lowest percentage. Even if Sailwave could do the other stuff, I'm pretty sure that would be a stumbling block.

[As an aside, my club has the same kind of goal as you seem to have. We calculate race scores kind of like you do but then divide each such score by the total possible points for that race so that each race is in essence a percentage score. We then simply add the percentages from each race (the percentage is zero for a race that you don't race in) and allow discards (about one for every six races) at the end. It is not quite the same as a true "percentage of perfection" system but it is pretty close and works well to encourage boats to come out for as many races as possible. If you want more description I can provide it or search back through previous messages on the Sailwave User Group website.]

Art

> races that are abandoned or cancelled]})]

On 2/19/2013 1:53 PM, Tom Owen wrote:

I tried to migrate to Sailwave last year but was not able to get it to meet
all of our current scoring requirements. We have 2 unique scoring
requirements that I was wondering if Sailwave can handle:

1. Each yacht in the fleet is required to perform RO duty from time to
time during any of the series. We award the lesser of (average finish
position for all completed races in the series truncated to the next smaller
integer) or (number of boats starting + 1). As the series progresses, any
value for RO duty could change weekly depending on how the yacht performs. I
believe that Sailwave supports this via an average only, and not a
truncation, and would require a manual entry for the number of boats
starting +1 if that value were less than the truncated average finish
position in the series.
2. We use a slightly modified PHRF of the Chesapeake High Points system
(http://www.phrfchesbay.com/2012hprules.pdf) as well. There are 3 series
for Low Points (see above) but all races from each series are included in
the high points. The scoring for high points is:
      [High Points (always a fraction<= 1.0)] = [Total of
Points Earned* for the Year] / [(Total max points possible** if the yacht
won every event in which she started) + (total number of scheduled races
that are scheduled/completed {[normally 24 (8 for each series)] - [number of
races that are abandoned or cancelled]})]
    * "Points Earned" are one point for starting, one point for
finishing, and one point for every boat beaten.
    ** Total max point possible is the sum of (Number of boats
starting + 2) for each race in which the boat came to the start line.
    One throw-out is allowed for every 6 races. Throw-outs will
be determined by the Chief Scorer to achieve the highest possible score for
the yacht. Note that the highest possible score may be the result of a
yacht not using all of its throw-outs.

In addition, the Chief Scorer (aka me) would like to enter the results only
once.

Currently we use Excel and VBA that I developed to do our scoring, but I
would like to use a supported product. This allows an easier transition to
a new chief scorer in the future.

Thanks,
Tom Owen
Dahlgren Yacht Club
Dahlgren, Virginia, USA

4

Art,

Thanks for the comments.

  •      With respect to the Bonus Points, we do not have any Bonus Points.  However, for completeness including it in the numerator and assigning a value of zero works.

  •      We do have a minimum number of races to qualify.  I should have mentioned that, but the real crux is the calculation of the actual high points value.

  •      With respect to the addition in the denominator, the intent is encourage participation as you stated later.  PHRF of the Chesapeake does that with a flat 30, but we do it by adding in all of the completed races (scheduled – cancelled or abandoned) for the season.  Theoretically if a boat scored 1<sup>st</sup> in every competed race their score would be 1.00.  Using a 100 multiplier to get an integral percentage that would be fine.

  •      With respect to the number of throw outs, for a boat that always finishes 1<sup>st</sup>, you are correct.  However, for boats that do not always finish first and depending the total number the came to the start (some nights it may be twice as many as other nights), the individual contributions to the numerator and denominator are different and result in a different final result when the division is done.  I have asked world renown mathematicians for a closed form solution, but one does not exist.  Therefore to get the “best” score, each case has to be computed.  While just adding the best individual percentages works in many cases, it is not guaranteed to find the best case. I did not realize that US Sailing had a similar long series suggestion.  We may consider moving to it which may reduce the complexity of the calculations, but determining the races to exclude is still problematic as the suggestion states “Also, the High-Point Percentage System has the advantage that a boat that wins a race in which a large number of boats compete is rewarded more handsomely than a boat that wins a race against a smaller number of competitors.”

Thanks again for the comments.

Tom

···

From: sailwave@yahoogroups.com [mailto:sailwave@yahoogroups.com] On Behalf Of Art Engel
Sent: Friday, February 22, 2013 9:45 PM
To: sailwave@yahoogroups.com
Subject: Re: [sailwave] Can Sailwave Do Our Scoring?

Tom,

I think you might have a typo in your write-up.

If I look at the PDF you referenced from Chesapeake PHRF their formula
is POINTS_EARNED/TOTAL_POINTS_POSSIBLE. I take it that is your goal.
Chesapeake PHRF uses the same race points as you but they also allow
“Bonus” points. So their “TOTAL_POINTS_POSSIBLE” is the total points if
a boat had won every race AND the total maximum “bonus” points. You
don’t mention “bonus” points so perhaps you meant your formula to be

[High Points] = [Total of Points Earned* for the Year] / [(Total max
points possible** if the yacht won every event in which she started)]

This is not an uncommon calculation (US Sailing recommends almost the
exact same thing for a long series). See
http://raceadmin.ussailing.org/Rules/Long_Series.htm . However, most
folks multiple the ending fraction by 100 to come up with a whole number
equal to a “winning percentage” number.

One important feature of a “percentage of perfection” scoring system
isn’t mentioned by you - a minimum number of races to qualify for the
series. Otherwise, the boat that wins the first race should never come
out again as its percentage will be 100% at the end of the series.

Your message mentioned adding the total number of races held to the
denominator but I don’t know why you would want to do that. A
“percentage of perfection” calculation is intended (at least in theory)
to give an equal chance of success to boats that do fewer races. But, by
artificially increasing the denominator you penalize boats that do fewer
races. That might be intentional but it goes against the basic idea of a
“percentage of perfection” calculation. Plus, I think you meant

(total number of scheduled races that are completed)

rather than

(total number of scheduled races that are scheduled/completed)] -
[number of races that are abandoned or cancelled])]

since the latter would seem to result in two less races counted for
every race that is not run as scheduled.

THROW OUTS / DISCARDS

I cannot think of a situation where a boat would be better off with
fewer discards. If a boat has all 1st-place finishes then her score will
be the same (100%), not better, with fewer discards but in all other
circumstances I think a boat’s series score would be worse with fewer
discards. A percentage of perfection system doesn’t normally use
discards as that goes against the very idea of the system. Plus, to
determine which race scores to discard you would have to divide each
individual race score by the total possible points for that race and
then discard the scores with the lowest percentage. Even if Sailwave
could do the other stuff, I’m pretty sure that would be a stumbling block.

[As an aside, my club has the same kind of goal as you seem to have. We
calculate race scores kind of like you do but then divide each such
score by the total possible points for that race so that each race is in
essence a percentage score. We then simply add the percentages from each
race (the percentage is zero for a race that you don’t race in) and
allow discards (about one for every six races) at the end. It is not
quite the same as a true “percentage of perfection” system but it is
pretty close and works well to encourage boats to come out for as many
races as possible. If you want more description I can provide it or
search back through previous messages on the Sailwave User Group website.]

Art

races that are abandoned or cancelled]})]

On 2/19/2013 1:53 PM, Tom Owen wrote:

I tried to migrate to Sailwave last year but was not able to get it to meet
all of our current scoring requirements. We have 2 unique scoring
requirements that I was wondering if Sailwave can handle:

  1. Each yacht in the fleet is required to perform RO duty from time to
    time during any of the series. We award the lesser of (average finish
    position for all completed races in the series truncated to the next smaller
    integer) or (number of boats starting + 1). As the series progresses, any
    value for RO duty could change weekly depending on how the yacht performs. I
    believe that Sailwave supports this via an average only, and not a
    truncation, and would require a manual entry for the number of boats
    starting +1 if that value were less than the truncated average finish
    position in the series.
  2. We use a slightly modified PHRF of the Chesapeake High Points system
    (http://www.phrfchesbay.com/2012hprules.pdf) as well. There are 3 series
    for Low Points (see above) but all races from each series are included in
    the high points. The scoring for high points is:
    [High Points (always a fraction<= 1.0)] = [Total of
    Points Earned* for the Year] / [(Total max points possible** if the yacht
    won every event in which she started) + (total number of scheduled races
    that are scheduled/completed {[normally 24 (8 for each series)] - [number of
    races that are abandoned or cancelled]})]
  • “Points Earned” are one point for starting, one point for
    finishing, and one point for every boat beaten.
    ** Total max point possible is the sum of (Number of boats
    starting + 2) for each race in which the boat came to the start line.
    One throw-out is allowed for every 6 races. Throw-outs will
    be determined by the Chief Scorer to achieve the highest possible score for
    the yacht. Note that the highest possible score may be the result of a
    yacht not using all of its throw-outs.

In addition, the Chief Scorer (aka me) would like to enter the results only
once.

Currently we use Excel and VBA that I developed to do our scoring, but I
would like to use a supported product. This allows an easier transition to
a new chief scorer in the future.

Thanks,
Tom Owen
Dahlgren Yacht Club
Dahlgren, Virginia, USA