PY Rating Qestion

Hi

This not a Sailwave question, however, I will ask anyhow

I have heard some debate or opinions on the PY rating system.
Essentially that the PY system only works for races that are greater than 60 minutes in elapsed time.

To my understanding of the rating system or my knowledge of statistics that there is no real basis to this given that the rating system is attempting to level field using statistics.
I have read the RYA guidelines got PY system, and there is no mention of this view.

I can see how the longer races will benefit the consistently better sailors or boats that have a slightly generous PN.

So has anybody got a view?

Ta

JoeW

Complete bllx IMHO;)
With any handicap system there will also be debates about the start line effect (slower boats get rolled off the start line), but then the wind sometimes picks up after the faster boats have finished, etc., etc…
Mike
Lancing SC

···

— In sailwave@yahoogroups.com, “iolarjoe” wrote:

I have heard some debate or opinions on the PY rating system.
Essentially that the PY system only works for races that are greater than 60 minutes in elapsed time.

The derivation of the PY system is from results of tens of thousands of races of all durations and weather conditions submitted be participating clubs. So you can have confidence that as a basic standard it is equitable. But as your club may have its own specific circumstances the RYA have a method for adapting PY ratings specifically for those circumstances. By using their method your results also grow the database from which the “published” PY ratings are derived.

And as a Sailwave user you have the tools required to upload data to the RYA PYS site and investigate the PY your fleets are actually achieving.

Ian…

···

On 13 June 2013 14:28, Mike mike.croker@phonecoop.coop wrote:

— In sailwave@yahoogroups.com, “iolarjoe” wrote:

I have heard some debate or opinions on the PY rating system.
Essentially that the PY system only works for races that are greater than 60 minutes in elapsed time.

Complete bllx IMHO;)
With any handicap system there will also be debates about the start line effect (slower boats get rolled off the start line), but then the wind sometimes picks up after the faster boats have finished, etc., etc…

Mike
Lancing SC

In general, I would say that the shorter the legs the more results are
going to be influenced by luck. In other words, longer legs will mean
the results of a race are more likely to be based on skill and boat speed.

The reason has to do with windshifts and starting position. If a boat
starts near one end and the wind immediately shifts that way then the
boat will have a significant advantage. That can sometimes (often?) be a
matter of luck. With longer legs, a better-sailed or faster boat will be
able to overcome that initial disadvantage. Longer legs often translate
into a longer race.

So, it probably makes some sense to set a minimum distance (time) for
races if you are going to use the raw results to imply potential boat
speed. But, that isn't going to improve your accuracy by 90%, more like
5-10% in all likelihood - of course, I don't think there is any way to
really measure the accuracy so that is just a guesstimate based on gut
feeling.

Art

···

On 6/13/2013 6:12 AM, iolarjoe wrote:

Hi

This not a Sailwave question, however, I will ask anyhow

I have heard some debate or opinions on the PY rating system.
Essentially that the PY system only works for races that are greater than 60 minutes in elapsed time.

To my understanding of the rating system or my knowledge of statistics that there is no real basis to this given that the rating system is attempting to level field using statistics.
I have read the RYA guidelines got PY system, and there is no mention of this view.

I can see how the longer races will benefit the consistently better sailors or boats that have a slightly generous PN.

So has anybody got a view?

Ta

JoeW

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