Charleston RW

Jake, that is a nice summary.

The only thing I would add is that the variance due to boat design is much smaller then the variance between sailing ability. See the F16 discussion.

Second point... the nature of the rules contribute to the lack of precision.
Consider... that for a 30 foot One design boat...and 10 boats in the race... a port tack boat coming into the lay line TIED for first with other perfectly sailed boats will loose three percent in time when the rules force them to bail out and fall into line in 10th place to round the mark. So... the variance will be 3% racing on time even in one design boats because of the rules.

Taking Times will not do better then 3% for 10 30 foot boats and so on.

The major advantage is transparency. Numbers don't lie... the formula is evaluated against the real world. considered by a committe for accuracy and fairness, and applied to all boat classes equally and it is published and sanctioned world wide.... you plug and chug to get your rating...

Everyone has an opinion on the accuracy of the table. If we want to average opinions... that is called PHRF and it can work... it is just not very transparent.

There is no argument that Sarah and JC turned in the rating on the Nacra 17 against joe noname who has the only A cat in the race.... So.. they have created a very hard rating to sail the N17to... The weekend sailor cant sail the boat to it's rating and compete against joe blow on the A cat...
The bar talk about the formula lasts 10 seconds.... the bar talk about Sarah and JC versus joe blow on the A cat lasts indefinitely and is meaningless.

Choose.

Another area that appears to be different are wind speed related corrections. SCHRS doesn't seem to factor this in. Realize it would be a real monster to try to simulate via mathematical calcs, but there are clearly differences in how boats behave as the wind comes up.

I guess that's a potential benefit of the empirically derived DPN system.

Mike,

I was studying that very thing when I was involved. The problem is that you need the rating to have some ability to creep up so that it can settle in. If it had no ability to creep upward, random noise or one human mistake in a submitted result could really unfavorably tilt the rating and it would have no ability to correct.

Darline shared with me the original files and a theory document that explained the calculation of the DPN handicap. While I used to be fluent in Fortran at one time, the statistical part of it was pretty advanced and a bit over my head without an investment in some statistics book-learnin' on my part.

While we were examining this issue, I had considered a way that a rating can lower at a full rate but for it to correct in the higher (slower) direction would be at some reduced rate...say 25% of the rate that it could decrease. That would give it some ability to settle in and account for the outliers in the data while at least slowing down the aging fleet ratings. There were several cases of good sailors taking advantage of this rating creep at the time - but I haven't seen any of that in a long while.

all of this depends on getting submitted results and, even if we could make that happen, it's a monstrous task to get those results entered into a homogenized format that can be used for crunching.

jeff R

Portsmouth uses wind speed ratings or DPN. DPN is 80% of the B4 rating... eg 12 to 18.

SCHRS and Texel use righting moment in the formula so it is considered. Texel did calculate two ratings... hull flying and displacement however most of the Dutch clubs did not use the two ratings because the variance of the sailors was greater then the rating difference at the club level... (basically it wasn't worth it)

would accurate VPP information from the mfg. be of any help?

They would be biased to make their polars look as stellar as possible (preventing the sandbagging argument) to sell more boats.

It would provide data on point of sail and tws

Not sure how you'd crunch that into a particular platform's ideal speed/time around a course...

What we need is a way to make entering the data easier/automated...

Mike

I have a feeling very few small catamarans have accurate VPP data. The system is so dynamic that it would be extremely difficult to develop an accurate model that covers the different sailing modes and the transitions between them.

I have sailed a fair amount under the texel system in Singapore and Thailand and it works very well. There really hasn't been a time where I felt a boat didn't deserve the place the received.

Do we even have that much good data to enter? What makes the data useable? I'm assuming we're taking about skilled guys racing open class with somewhat consistent results.

surely someone could figure that out along with the calendar.

What is needed to set up the electronic timekeeping thing like the runners use (those little FOBs you wear on your shoe)?

do you need to stretch an antennae across the finish line or something? That would be hard for boats (mast or daggarboards), but if it's some directional antennae (or two), it could probably work to record reasonably accurate finish times for boats which could then automatically load in whatever program (sailworks or whatever)...

If USS hosted the regatta software cloud thingy, maybe your results could be instantly available to USS?

Then the only thing would be to lodge protest hearing results ?

You PROs probably know more about the inner workings of these regatta programs...

Agreed. I had discussions with Colin Jenkins (the creator of Sailwave) and he was able and willing to include a

submit to US Sailing

option in the software. We just needed US Sailing to setup an FTP site to receive the information. It was at the time that the US Sailing website was being completely overhauled and Darline and I couldn't seem to get any attention about it... though I really wasn't screaming about it I know Darline did have some conversations to that point.

However, I think Sailwave is INCREDIBLY powerful but has gotten a little overly complex to expect everyone to use it. If you are not using it frequently it's hard to remember how to set it up correctly. I use it maybe once a year and I struggle with it until that

oh yeah, crap...that setting

moment. Setting up an Excel spreadsheet is sometimes easier. It could benefit from some streamlining of the setup process and/or having several regatta templates to choose from at the get-go. Actually, I should probably contact Colin about that to see if he hasn't already thought of that.

We race every week under SCHRS with Nacra 20's, F18, F16 and A-Cat. There hasn't been much whining at the bar lately. None as I recall, even when the splits were under 5 seconds. The team that sailed best that week usually won. It is very difficult to argue with a formula.

Of course you would since the F18 owes other boats less time under SCHRS. I could find a lot of ways to argue with a formula that tries to cover something so dynamic as boat potential. Have you seen the number of variables that go into the formula? Those guys have put an incredible amount of brain power into it but who says it's any more accurate than our current Portsmouth numbers? How do you prove it? The fact that nobody complains is hardly proof of anything other than the fact people accept handicap racing for what it is.

Reference SCHRS rules

Well, real-time entry is the ultimate dream, but in this case, I was referring to making it easier to get existing data into the system, if for no other reason than comparing new/proposed systems.

There are so many systems in use, it's crazy. Everyone has their favorite, and when you work for as many different classes and OAs as I do, you learn to be OK with delegating to the local expert. Other times, you have to take ownership. It's sometimes a delicate balance.

Mike

Jordonna is in huge favor of SCHRS and is already reviewing our race results under that system.

Jake You must talk about Accuracy along with Transparency... it does not serve the debate to consider only one factor.

Accuracy assumes that their exists a perfect single number rating for a boat. Now... even if we knew that number... the fact is that the racing rules of sailing will add noise of a few percent. So...the precision of your finish time is plus or minus a few percent. Basically the tables use one decimal place and you can have two classes tie on corrected time even tho one beats the other across the line. Handicap won't resolve close finishes as well as one design. That is the nature o the game... Accuracy of any table is always debatable.

We obviously want an accurate ratings table and accept the limitations of finishing by time and not position. BECAUSE accuracy is in the eye of the beholder... we count on the national and international sanctioning bodies to declare one table is accurate and approved.

Of almost equal Value as Accuracy is Transparency... Do you know the factors used in generating the rating because it is likely that you (or someone) will disagree with the accuracy of the table for your boat or theirs. Transparency addresses HOW you get to an accurate table.

How you get to an

accurate

table of boats is one of three ways.
Accuracy is in the eye of the beholder SO...we count on the sanctioning bodies... ISAF and US Sailing to declare one or all acceptable. US Sailing declares three handicaping systems accurate. PHRF, Measurement and Portsmouth. They differ in transparency.

Portsmouth... collects data for yardstick and active one designs and generates the table. Problem is. Not enough quality data for new designs racing against the yardstick boats exist. All data have to be filtered. The races used to calculate a rating may be historical because 100 data points are used. The problem is with getting valid quality data and major corrections have been required to fix problems that were caused by bad data. One off boats get ratings (to be user friendly) that are not valid.

Measurement. A committee works out a formula based on the sailing physics, curve fits to data, etc etc. The rating table is based on the published formula applied to all boat classes and the measured parameters of a specific boat or class of boats (one design) Examples are MORC, HPR (Monohulls) SCHRS and Texel (cats.) This table is the most transparent.

PHRF... A committee works out their best judgment based on declared parameters and measured values and the observed performance on the race course.. This is a local committee which takes into account local issues like current etc.
Transparency is low because the committee meetings are private... but you can appeal your rating. PHRF tables exist for monos and big multis' PHRF tables differ a lot across the country.

I believe that SCHRS is the best solution for both Accuracy and Transparency PLUS it is sanctioned by ISAF.

Calling me biased is pretty unfair. Any given week we'll be racing on a Nacra 20 or F16, if we can't get the F18 mast up in time for a midweek race. Besides, we were racing under 2012 SCHRS tables which have the F-18 and the A-Cat as equals. Any given week we'd win or they'd win, depending on how much upwind vs. downwind work was involved and the wind strength. This was for a 2008 Nacra Infusion w/o long boards and older generation A's without curved boards or t-foil rudders.

That goes for the other classes. The newest F16 designs are equal in performance to the F18's, which isn't surprising since that was the design intent! I will say they are a tiny tiny bit faster in light air, but regardless of conditions the better sailed boat wins and the corrected time delta is on the order of seconds for a 1 hour course.

We ran the numbers both ways before switching. Maybe there was one boat that swapped positions with another using SCHRS vs. Portsmouth after an entire season of racing. The delta just isn't there and SCHRS is fully transparent, plus does a better job of handling one-off's like modified ARC22's.

Again, absolutely not defending Portsmouth above all others, but there is a process in place to get a provisional number for a new boat. The process is neither fast nor perfect, but is part of the program.

If you guys are serious about putting together a proposal to change to a new system, please be sure to include strengths and weaknesses of all aspects of the systems being assessed, including Portsmouth.

Mike

Portsmouth can be transparent but as I mentioned earlier, the statistics that go into it are complicated. Heck, I probably have the document that explains the math but few of us would probably understand it (Jamie Diamond is probably one of them). I would venture a guess that the complexity of it, and not having the original people available, would be a hurdle if we had data to compile.

That said, I really appreciate the energy (and people) that made DPN. They were brilliant people who built a system that has the potential to be an exceptionally accurate handicapping system. I don't have a problem racing under the numbers as they stand today - I feel like they are fair and accurate. It also has the ability to adjust for different wind strengths that SCHRS does not - and Sam just stated how who wins under SCHRS depends on the conditions.

I made a MHC proposal in 2009 to use a marriage of the two systems - use a measurement based system (adopt from SCHRS) to establish provisional DPN number for a new type of boat until enough data is had to zero in on an accurate rating. We've been talking about this for a long time.

Handicap racing is what it is - and I don't expect it to be the ultimate test of my ability. However, for the reasons stated above, I prefer DPN if we can keep it actively adjusting.

God bless Dick Blanchard (NAMSA) and Darlene Hobock (USSA) - long may they live.

Carl Reigart is the new leader, and he welcomes data, and ideas for growth.

How many OAs around the country, especially the deep south (GYA), wish to roll over to a new system such as SCHRS, Texel, or local club inventions?