Beginner questions: personal performance

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personal performance

Printed From: Yachts and Yachting Online
Category: General
Forum Name: Beginner questions
Forum Discription: Advice for those who are new to sailing
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=11695
Printed Date: 12 Aug 25 at 9:55pm
Software Version: Web Wiz Forums 9.665y - http://www.webwizforums.com

Topic: personal performance

Posted By: Kev M
Subject: personal performance
Date Posted: 02 Oct 14 at 9:10pm

I sailed a supernova for the first time the other day. The result was pretty poor even by my standards but to be expected having not helmed for a year.

Is it possible to calculate my own py compared to the boat's py?

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Successfully confusing ambition with ability since 1980.

Replies:

Posted By: JimC
Date Posted: 02 Oct 14 at 10:18pm

It's reasonably easy to do something on those lines. What I do to calculate personal handicaps at
my club is to stuff all the results into a spreadsheet and calculate each corrected time as a percent of the winners ct. Average everyone's percentages and there you go. Club hotshots will be between 100 and 105%, beginners 120% or more.

If you want your personal PY for that race then multiply your real PY by the percentage, and the result will
a) depress you and
b) enlighten you to how much value there is in whinging about the odd 5 points on a boat's PY

Posted By: jeffers
Date Posted: 03 Oct 14 at 9:53am

I seem to recall that Sailwave can give you an achieved PY as well (against the leading boat).

Not sure what else it can do though!

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Paul
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D-Zero GBR 74

Posted By: Rupert
Date Posted: 03 Oct 14 at 11:54am

You can work it out on a calculator too, if you have the list of results with elapsed and corrected time. I usually end up doing it by trial and error, but I'm sure anyone better at maths than me would know how to reverse the corrected time process.

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Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686

Posted By: jeffers
Date Posted: 03 Oct 14 at 12:57pm

Does depend on where you set your datum point as well. Sailwave assumes the winner sailed to PY from what I can see and then calculates the BCR from that (which I guess is the kind of thing you are after).

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Paul
----------------------
D-Zero GBR 74

Posted By: Rupert
Date Posted: 03 Oct 14 at 1:23pm

I suppose really it should assume that the mid boat sailed to PY, but that would be a bit of a lottery, I guess.

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Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686

Posted By: AlexM
Date Posted: 03 Oct 14 at 1:26pm

Or do it like the PYS website and use normal distribution on the fleet

Posted By: Kev M
Date Posted: 05 Oct 14 at 4:07pm

All sounds quite complicated for a simpleton like me. Essentially it seems there's no way to measure your performancr against the recognised performance of the boat because you have to measure yourself against someone else in the race wuo could be sailing above the recognised performance of their boat.

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Successfully confusing ambition with ability since 1980.

Posted By: Rupert
Date Posted: 05 Oct 14 at 9:12pm

Something like that, Kev. All you can do is compare your performance against other sailors, just like in fleet racing.

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Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686

Posted By: marke
Date Posted: 06 Oct 14 at 9:28am

Kev

You are right that it isn't possible to compare in isolation your personal performance against the 'standard' performance for your boat. However if you race regularly in a fleet of say 15 or more boats, you can compare your performance against your peers and see if it is improving over time.

In effect you use the PYS algorithm to get the personal PN for a race (PPN).
      - calculate the average corrected time for all finishers
      - remove all boats that have a CT slower than the average corrected time + 5%
      - recalculate the average corrected time (ACT) for all remaining boats
      - use the formulae PPN = ET * 1000 / ACT

This is effect compares your performance against an average of your peers.

Our race management software automatically produces PPNs for everyone racing at the club as part of the results calculation - and members can check their data (which goes back 3 years now) - and average it over any period they choose. It is very useful when coaching beginners as they tend to make fairly significant improvements over the course of a single season. I have started sailing a different class of boat this year which is rather more traditional than most of the boats I have sailed - I can see from the data that I appear to have improved by around 10 points if I average the first half of the year against the second half of the year - slow but at least I'm getting better!.

You can also use the same calculation to average over groups of boats (classes) to help with decisions on local PN adjustments.

Mark