Rating rant

Just a quick post to see if there is any movement on updates for the SCHRS/ Texel / SwelLYS etc or US/ Aus/ UK PY's ratings for 2009 and if they will ever get in alignment? I know all about the measurement V’s history of the systems but in each group ( measurement or history) there is such variations. And one other questions if SCHRS is seen as near perfect why is it not used by all ISAF nations? Why is PY still popular and a lot of nations have their own measurement systems.

It would be interesting to see a selection of boats, new and old, light and heavy, high sail area and low sail area, in all the measurement rules and PY rules and see the variations, what you will see is huge difference between boats in each measurement and PY systems. Who chooses?

I’m like a dog with a bone on this subject I just can’t let it go! I believe no boat can rate to a single number for all conditions, it’s just impossible, we just have to live with a so-so system. but can we not agree on one system and get rid of the rest.

I'm in favor of dropping the U.S. Portsmouth system and adopting SCHRS. Imo, a measurement system is more accurate than a reporting system and is easier to use.

I disagree - I think the perfect solution is a combination of both. Use a measurement based system to establish initial ratings or modification factors and to eliminate the [brackets] of uncertainty in the Portsmouth ratings but continue to use performance data to fine tune the numbers. I'll admit to being astonished at how accurate the measurement based systems are but there are still issues and there will continue to be new issues in the future with new performance gaining design features that are really difficult to quantify...canted boards and/or lifting foils for an example. How much performance to you attribute to a canted daggerboard at, say 15 degrees? what about 45 degrees? Over the last several years, I've sailed a Nacra 20 against F18s and I've seen F18's become considerably faster in the moderate and light breezes though none of their parameters have changed. A measurement system just can't have enough complexity and be manageable to compensate for the differences between a box rule development class and a strict one design class that hasn't seen a significant sail shape / performance design change in 15 years.

My point is that where the measurement based system gets really complex and begins to falter, the performance based system can take over quite easily to refine the figures.

Wind range parameters in the Portsmouth system make the system very accurate when they are used (which is less often than it should be).

There are some other issues with performance based systems with rating creep as boats become older and sailed less by the experienced sailors...but that can be managed by establishing a lower ceiling for the rating based on the measurement rating of the platform.

Scooby,

Forgive me if this has been explained before...

Why, in SCHRS ratings, are all one-up boats listed with 75kg crew and all two-up boats listed with 150kg crew weight? Or, without regard to class minimum crew weights?

I'd still like to see the issue brought formally to USS. Nothing lasts forever, imo, it is time for Portsmouth to be retired.

I've said my piece.

Why should it be retired?

I don't believe the reporting is being done adequately. I would offer the stability of the ratings as evidence i.e. if any classes ratings do not change over time either performance has remained constant or the reporting is not being done. USS can not change a rating if there is no data to indicate a change necessary.

It has been brought to the Multihull Council and we have had some pretty thorough on-line discussion. It is a topic for the meeting in Denver. I'm not sure exactly what the Multihull Council can do about this, but we're looking into it. It seems to be more of an issue today than it has been for people in the last few years. Make sure you let your Area Rep know what you think.

Pete

Do you think that official measurements by certified measurement officials will be done MORE often?

Do you think that one-off-frankenboats will carry official measurements?

The manpower required in either system is roughly equal.

Also, unless you've hacked into Darline's inbox, how do you know if data is being adequately reported?

"Also, unless you've hacked into Darline's inbox, how do you know if data is being adequately reported?"

That's uncalled for.

OOOOoOk. Whatever. The question still stands. What hard proof do you have that results aren't being reported?

If your area rep is on an F18 and the gripe is the difference in the numbers between F18's and N20's, do you think it would allways be effective to let them know? Not complaining about our rep, but wtf? The F18 sail plan has evolved quite a bit while the N20 is gathering dust for the past 7 years and the numbers don't seem to reflect this. I mean, seriously, what could our rep do if we thought it would make any difference to complain to them. What would be the next step for our rep?

BTW, I cant believe that got censored! It wasn't even a curse.

Have a frank conversation with your Rep - I find that they're all pretty straight up about bringing things forward. If you don't get the sense you're being heard, bounce it up a floor. General concerns with ratings are, of course, the purview of the Portsmouth Committee, which is not a Committee under the Multihull Council as some seem to think. All the Council is considering is looking at the various options and listening to the concerns in order to determine if action is needed, determine what that action may be, and then work to see the action implemented. We can't (and wouldn't) tell the Portsmouth Committee what to do or how to do it. We can spend some time looking at concerns from around the country, distilling common issues, and carrying the message in a concise way forward. We can also make national-level recommendations (like the multihull courses) for racing, which could include an option for using other ratings systems for some events (like distance races).

I'd heard a lot of concerns about the N20 v. F18 number some years ago, but thought that once the F18 number dropped to 62.4, people were pretty satisfied. Do you have some race data that needs a look?

What about a rating for the skipper level? I could use the help.

It's not being reported accurately or very often. I've had discussions with Darline about it. She has to do an incredible amount of manipulation to get the data that she receives in an operable fashion and a lot of people don't use the variable wind ratings (which are much more accurate than the straight DPN number).

One thing I started to pursue was with Colin - they guy that created Sailwave. He's already doing this with the RYA...but we talked about having an option in sailwave where you select "send results to US Sailing". If you have an active internet connection, it would send a data file to a US Sailing managed FTP site with exactly all the information that can be immediately imported into a database that would crunch the rating calcs.

It takes a lot of coordination to make this happen but Colin is ready and willing to add it if the details can be worked out on the other end...that's where I left it.

Go bowling instead.

I feel that the F18 / N20 numbers are relatively fair. The problem I think Lee runs into is distance racing - and it's going to be really tricky for any handicap system to accomodate that unless you add the complexity of an "angle of sail" factor.

For the record the Area D South data I can get my hands on is given to Darline in SailWave format with wind corrector mods used.

Not to complain, (who me, complain?)

But someone mentioned if and when the modification factors are being use correctly in Portsmouth.


As I said, not to complain, but in the recent past, if I was in a portsmouth class, (which I usually was on my N6.0), that only the standard DPN #'s were used, and no wind corrections, even in bouy racing.

And granted, othing is perfect in this system, and it does usually work pretty well. Maybe thats why it would seem several one design classes are once again emerging.

This is the information that I was seeking. Pure conjecture doesn't get us anywhere.

We also should consider what happens when classes are raced by themselves. Presumably you wont be able to run numbers on a race where the boats aren't starting together. This would make classes like the F18, and regionally NF17 relatively stable since they are class racing in most cases.

Todd, you want the numbers done right volunteer to crunch the numbers. It's been my experience the OA will happily hand off this task.

As have ours too. This is conjecture - but I suspect that most of the results that the Portsmouth Committee receives from multihulls come from the Alter Cup Qualifiers since they have to submit them and they have to use the wind correction factors.

I think you'll find none of the evolution of F18 sails would result in a change to the SCHRS rating, as I believe its already based upone the extremes of the box rule. So you more likely to get an adjustment under PY than under a measurement system.

Todd

the fact that the RC did not use wind adjusted numbers to determine your finish position is irrelevant to calculating the rating for the boat.

All that was needed was for them to turn in the elapsed times and the wind speed for each race. They don't even care about the second boat in the class finish time.

TikPete... its called a yardstick for a reason.

The Primary yardstick is a thistle. the rating will never ever change for a thistle... its the standard which all other boats are compared with. Other boats are designated as secondary yardsticks .... their ratings change very very slowly.

If a rating is not changing... then the boat is being optimally sailed relative to the yardsticks.

Or... the actual speed improvement can not be measured with the amount and quality of the data collected.

the Mid atlantic region could only turn in two or three regattas worth of weekend buoys race data in 2008 because most of the racing is now one design and times were not recorded.

Jake's proposal that statistics will fine tune a measurement rating is merely a dream because the amount of data needed is just not out there to resolve small performance differences.

Even if the new Hobie F18 is a bit faster... Handicap racing will never measure the speed improvement due to the noise of boat racing against a Nacra 20 or a Blade F16.

He presumes that the measurement rating table is not accurate and requires some fine tuning with statisitcs.
To support this notion, he should at least identify boats in the measurement ratings that need some fine tuning with the performance data relative to each other. The sailors who use Texel or SCHRS are not out their complaining.

My view, is that the rating systems are about as accurate as you are likely to get. The differences are how they deal with changes and new designs in time. Measurement rules have a clear advantage.

There is a reason the ratings don't use several decimal places in the tables.

Most of the big boat ratings experts don't think you will be able to do better then 2.5%.... simply based on the nature of racing and the time of the race. Eg... if you don't get a lane on the first beat... you are slotted to a poor rounding round A mark... no matter how fast you are you can't use it on the first 1/4 of the race .... and the clock keeps on ticking.

It's a lot easier to get the data on a boat class measurments once then continually collect race results. If you get creative and change your sail ... then pay the 20 bucks and get it independently measured for your personal rating certificate.

The latest design by Ashy may be faster... but won't be measured using Portsmouth ratings of different class boats.

"the actual speed improvement can not be measured with the amount and quality of the data collected."

I suspect this is the case.

"Other boats are designated as secondary yardsticks .... their ratings change very very slowly." I'd like to know more about that if you have the time.

Thanks.

As I saild, it usually works pretty well, and I wasn't complaining.

I never blamed the numbers when I raced in portsmouth class. You have to have some kind of handicapping system, this one works well. Nothing is perfect, not even the perfect stranger.- Crissy Hines (spelling?)

'All that was needed was for them to turn in the elapsed times and the wind speed for each race. They don't even care about the second boat in the class finish time.'

My point was that, using different numbers at different wind speeds on different boats, could affect the portsmouth outcome, in a very close race.

For now, my vote, (as if I had one), is to stay with this measurement system.

Sorry, did not understand your point.

Yes, The windspeed ratings do a better job then a single number and the final result could change if they were used.

USPN is statisitical and not measurement based.

The issue is moving forward for the next 5 or 10 years... Would a measurement rule serve the USA better then a statistical rule. Times are taken for both systems and the PN System would not be starved for data and still could be used for clubs who did not want to switch.

Geesh - I'm standing right here...no need to refer to me in the 3rd person. I don't have time to digest why you believe I'm misguided here but will try to do so tonight.

SCHRS uses the average weight for a person worldwide as the defiined crew weight.

Class rules are exactly that; class rules. SCHRS does not impose any rules on the classes. If they wish to impose rules on their sailors, that is up to them.

There are no current plans for changes to the SCHRS rating engine at present; we are still waiting for a number of measurement certificates from some classes to be able to confirm their ratings, the Nacra F17 being the most pressing.

The variance in the finish times of the top 5 finishers of a one design class is about 2.5 to 5 %. This has to do with sailing skill and luck. It's the intrinsic variance in the game.

So performance based handicap ratings between different classes will have a limited precision as well and won't resolve the subtle changes in design that develop over time. It will take a lot of data to get this level of precision around an accurate rating. If a game changing innovation shows up while you could detect it in the results quickly, the PN system would adjust for that change over three years by the standing policy. Also... you would need a lot of data to measure a significant difference.

You suggestion to combine the two methods presumes that something is wrong with the current measurement rating set that must be fixed. I don't see that example in SCHRS or TEXEL You argue that design will lead to game changes and I don't see any game changers in the formula classes... In fact the curved A class boards proved not to change the game as far as the top guys in the class are concerned. Nobody is talking about the new Hobie F18 as a game changer.

Why change?
Sailors don't care about the race results being fair next year... they care about the race they just completed. If it's not fair... it's not fun and they won't be around in three years when the fair result could be calculated. For a new racer starting with an old design... it is tough enough to get up to speed to sail to their rating. If they think the ratings for the hot new boat are unfair.... its another barrier to keeping them in the game.

An alter Qualifer event is very difficult to handicap with a Hobie 14 racing against a Tornado or supercat 22 by design. Throw in rarely raced designs like the CFR 20 and the Marstrom 20 and its really tough to do this job fairly.

IMO a measurment rating would be fairer. I have come 180 on this one and Carl Roberts and Wouter Hinjck should have a quiet giggle here. Dave Inham and I disagree on the basic premise of handicap racing so he can't giggle. he doesn't like the whole idea. (grin)

The average weight for persons used for commercial vessel stability calculations in Australia is being increased from 75kg to 80kg. This is due to social changes affecting engineering rather than due to a safety margin being added.

A measurement system may/does work well for catamaran classes but they would be more inaccurate for monohulls. More measurement data would certainly be required for a dinghy because hull shape is more influential on dinghies than cats. Also, crew weight is anecdotally a more significant influence on performance for a dinghy than a cat so this would have to be accounted for.

"Sailors don't care about the race results being fair next year... they care about the race they just completed. If it's not fair... it's not fun and they won't be around in three years when the fair result could be calculated."

Agreed.

Why don’t we have just one rule? It’s a simple question, why does every nation need to have their own rule? If we all got behind one system and not diluting the pool of resources then the measurement rule will get sharper. At the moment there is holes in every rule, PY lack of results, SCHRS has boards aspect ratio, weight etc. We work off one set of racing rules why not one measurement rule? The current set of rating rules are flawed and don’t react fast enough to the market, we are talking years to react, in keel boats there is a big adjustment if a boat is seen as a rule bandit. We (I) have been on talking about this for years and still we get small to no movements. I think that is why most people like PY because it reacts much faster to the market than the measurement systems, it might not be perfect but at least it tries to keep all the boats in the centre, unlike the measurement rules that cannot see the difference between stock sails and custom sails etc, okay I'm ready to get flamed

flip flopper

Mono's also plane and have symetric Spi's this also makes a massive difference (I know the Shearwater Cat has a Sym).



What is wrong with aspcet ratio is is the most dominant factor in "normal boards".

Very thin boards do not perform at low speeds (I'm talking about aspect ratio > 6)

Very fat boards do OK in low speeds but suffer in fast.


Someone could choose to design very short and thin boards that get hit quite hard unser SCHRS, but why do it? Why would someone choose to design someting that will perform badly?

So True.... but better to be on the right side of history eventually.... (see Bush v Gore)

I'm so touched to be called a Flip Flopper I feel as if I've made it, Wow! did you come up with that all by yourself or did your baby brother help you? What a wingnut! ( Sorry David Ingram)

I don't think he was talking to you. Read a few posts before yours, then apologize.

"IMO a measurment rating would be fairer. I have come 180 on this one and Carl Roberts and Wouter Hinjck should have a quiet giggle here. Dave Inham and I disagree on the basic premise of handicap racing so he can't giggle. he doesn't like the whole idea. (grin)" Mark Schneider

Okay, I'll just crawl back into a hole here, jumped the gun sorry! man this is hard to say.

Mark,

I still haven't had time to read your post, but here is the short and sweet about the shortcomings and advantages of each system:

Measurement based system:

Pros:
- can quickly establish numbers on new platforms or modification factors

cons:
- can be cheated by designing or modifying boats within the gaps of the measurement system (see monohulls)
- cannot account for small (but sometimes significant) refinements of sailshapes, foils, canted foils / lifting foils, etc.
- caculation is complex and has to be applied by an organizing body (so no savings there over portsmouth)...probably have expenses related to measurers as well

Portsmouth:

Pros
- CAN account for minute design changes because only the boat's performance is measured
- Cannot be "cheated" around by new boat designs since ratings are based on actual performance and not hard physical design measurements.

Cons:
- rating creep can soften older platforms that are not as well maintained and typically sailed by less experience sailors leads to inaccurate ratings (an area that can be exploited).
- new or scarce designs are difficult to establish accurate numbers on which can take several years to settle out an accurate rating.


Mark - can you sum up quickly (I know, it's hard) why you think the measurement based system is MORE accurate?

OK - that wasn't fair of me so I re-read your post. I have the following comments.



Portsmouth is reasonably accurate today. Even if we couldn't get more data by making collection and calculation easier, there is more than enough data available to make a measurement based system incredibly more accurate.



Actually, yes it will. The difference will be small but statistics are statistics. If the new Hobie F18 gets around the course faster, it will show in the performance data. Why do you think it will not?



Mark, neither system is as accurate as it can be. Have you ever raced monohulls under a measurement based system? It's awful. The system sucks so badly that they have local measurement modifications that are established by other yacht clubs to hedge the local mods for different boats based on the political atmosphere. It's ridiculous. If you're not hearing the complaints, you're not listening closely enough.



Well..gosh...then why change a thing if they're as accurate as they can be? Please show me the accuracy advantage of the measurement system - you've not provided one piece of evidence. I do agree that a measurement system can respond more quickly to new designs but I also agree that portsmouth can better respond to the small refinements in boat design that the measurement system cannot - which is exactly why I propose a marriage of the two systems.



Yes, you're right. Texel does not use ANY decimal places because it is a measurement based system that realizes it's inaccuracies. Why do you think Portsmouth USES decimal places? Because it's more accurate me thinks.



So you think everyone's just going to pony up $20 for a measurement when they get a new main? you're in the dreamasphere there.



Why not? If you are suggesting that it is because a top a-cat sailor racing with a top a-cat mainsail won't be racing handicap very often then I agree with that sentiment...so what? A marriage of the two systems wouldn't care.

I can't believe I'm saying this - but where's Wouter in this discussino? He and I were working on a combined system to overcome the shortcomings of both systems about four years ago and had started the beginnings of a website before he pissed me off over something trivial.

Well... it really was meant for you and it was meant as a joke and not as a boot in the nuts. It does apply to Mark's post too, (thanks for pointing that out Todd) still meant as a joke. I just haven't been up for a good sh!t fight lately all the sailing has taken it right out of me.

Another soft spot in the DPN system is when a class doesn't or rarely races around the bouy's. This means new data is never submitted for the class and their initial number which is pretty much a WAG never changes.

I do like the hybrid system Jake scoped out earlier in this thread. Did I just say I "like" a rating system... that can't be good, I need to pull back on the meds.

Introduced such a system about five years ago. I can vouch for the fact that it works very well on a local basis. Good spread of boats winning races and fewer **ssed off sailors. The reason is someone listens to them and acts. It only takes someone to get off their backside, look at the local results and see what is happening. Get the participants then to agree to the adjustments and agree to reviews as appropriate.
The advantage is this system takes into account the local sailing environment and local sailors, after all this is where it is to take place and who it is to benefit. The only advantage of an inappropriate system is to the competitor with an under-rated boat.
Get your heads together at your local club and work on a proposal using last seasons results. Model these figures into the finishing times and look at the spread of results. Stop when happy and agreement is reached. If necessary shadow next series to verify new figures. What have you got to lose?

With time it could maybe be incorporated with other clubs data for regional figures.

Cheshirecatman

So your are measuring the boats and assigning a number then you're using your race results to fine tune the number? If you're not then it's sound like you're using DPN and then adjusting the number regionally. This has been done at lot of clubs for a long time and doesn't address a system used nationally. This thread was started in an effort to get one system globally your system could create hundreds of variants globally. Okay I'll come clean... I'm not a fan of tweaking the numbers regionally. It's a bit PHRFish and that my friend is word that needs to be censored.

Please indicate, for the record, that I did not use the phrase but merely made reference to it.

Look, Portsmouth works pretty well and we've watched the F18, N20, H16, F16...all these numbers work themselves out. It's big glaring weakness is new boats and boats without much data (like Dave pointed out, one design boats that don't compete much in open class). It's strength is that it's flexible. It's weaknesses can be overcome by applying the strengths of Texel or another measurement based system for the numbers that have relatively few points of data (the numbers with brackets).

To those who oppose Portsmouth, what SPECIFICALLY, do you see as the weaknesses of the system that cannot be solved by applying a measurement based system to it?

Having raced under the PH#! system, I can tell you that its all about politics and playing with your number and little to do with what happens on the water.

What? Where did that come from? There's politics in everything...but still. Are you saying Portsmouth should be trashed?

Jake, knock back another cup of coffee and reread Tad's post :-)

SCHRS is used as base and default. It it used as a tool to correct anomalies found in club racing, usually with the extremes with smaller or larger more extreme cats. No rating system will ever be ideal and one design impractical at local level. So you either moan about it or do something. We decided to do something. It's not perfect and never will be. If someone considers a rating unfair it is reviewed objectively. As stated it is run locally for local sailors and appears to work in that no sailor goes out with the opinion he cannot win because of his rating. Forget any preconceived ideas you have about national schemes and try it. Even if you only do it as a paper exercise you may actually see some benefit to it. If you don't you will be stuck with schemes you are not happy with based on wide data with possibly very little influence drawn from your local sailing situation.

You have a better solution?

Cheshirecatman

No No No

I'm talking about the PHRF system. I sail on a J29 during the summers that litterally has ratings wars with a C&C99 in the offseason. Whoever wins is whoever had the latest ratings knock. Its really quite silly.

the system is inherently flawed if elapsed times are hidden from the public.

I'm not saying don't use local variants. Clearly it works for you and no matter what system is adopted or modified nationally it will not impact the local clubs in any way, you guys will do what you think is best for your club. I'm just looking at from a different level.

Me personally, I'll never support a system that is based on a subjective review it's just too prone to manipulation.

Geesh - I'm standing right here...no need to refer to me in the 3rd person. I don't have time to digest why you believe I'm misguided here but will try to do so tonight.

Now thats funny!
Did you guys see my post about how things have changed? Things used to be so much simpler, but those days are gone. When Franken Boats show up at regatt's that I help manage, it's hard to get an accurate number. But today, there are alot 1 design boats that are racing DPN(5 or less which didnt constitute a class), and then you have an A cat, a handful of F18's, a N20 or 2, a modifeid this and modified that, a H16 with no comp tip...you get my point?
Will we ever make everyone happy? naaaa

Aaa...coffee chugged...point taken and agreed with.

so we have three schools of thought here:

A) everyone will never be happy so there's no point in putting any energy in making the system better

B) Portsmouth Stinks and we should use a measurement-only system

C) Our existing diametrically opposed systems can be improved by merging the two and utilizing the strengths from one to offset the weaknesses of the other.


Though I agree that someone somewhere will always be griping, it's no reason to not make a system better than it is currently. C sure seems to make the most sense to me.

In the short term, what if you were to score a regatta using both Portsmouth and Texel or SCHRS.

i.e., sail a 5-race series but score it at if it were ten.

5-scores with Portsmouth and 5-with the measurement formula.

It would tend to "blend" the two and perhaps dampen the major flaws.

The main problem in my mind is the extra calculations and hence time needed to provide the results. It would take a very dedicated scorer to take on this extra workload.

Portsmouth ratings do not stink! I am not making that argument. I state the rating system is more or less fair.

The complaint is... The system is falling apart. For example a late season PN correction was petitioned for and granted to ensure a more or less fair table of ratings.

Why did that happen? The Portsmouth process is slow and requires a lot of data which cannot be obtained in 2009 and onwards. The reason to change is to consider LOOKING FORWARD WHAT IS THE BEST SOLUTION for the US Sailing scene.

Take the portsmouth races which should feature the top sailors racing a number of different classes.... the Area Qualifiers. These results are expected to have sailors who could race their boat to it's rating.

The participation and winners are not posted this year. Memory has
New England.... 2 particpants.
Mid Atlantic 4 participants
I suspect the average turnout would be around 5 to 7 boats.

Tradewinds 2009 approxx 5 boats in open class.

The biggest event was Area D South with 15 or so (memory serves).

My point is that the PN system cannot work with such a small amount of quality data.

will we make everyone happy? No, but we can make it better, no doubt. Whatever we decide, we need to all buy into it(bipartanship) and give it a valiant effort to get it right. If naysayers spoil the fun, then it cetainly wont work.

That would be easy if using Sailwave or similar software. You just check the box for which handicap system you want to use...combining them might be difficult but comparing them easy.

Then how come the F17 still has a peach of a rating then? Or are all the US sailors sailing them badly?

Last time I looked it was about 4% more generous under USPN than under SCHRS or Texel, We do not even have the up-to-date measuremnets for the F17 as no-one will send me one; I've been waiting 10 months! I made a guess last time I compared them.

Does ANYONE have a measurement certificate that confirms the data-points of the F17.

I never say the "protested" one form Carnac last year, and I have an owner pestering Nacra EU for one, but they do not appear to be able to provide one.

I think we're starting to get somewhere in this discussion now. The system did fall apart for a while but it had nothing to do with the system itself. It was because the actual calculation/database system was taken on by a new person with the goal of modernizing the software that manages it. The process quickly got complicated and there was basically no rating calculation taking place for over 1.5 years...the F16 fell squarely in this void. At present state, the previous computer system is in use again by Darline which is why we started to see some timely changes again. However, it is in need of some modernization....which would be a good time to implement some improvements if it's seen fit by the Portsmouth Committee.

Scooby

The Nacra 17 is a regional class. IF CRAM does not turn in their comparative data against the other starts... the rating will never adjust. (I have no idea whether they do or don't)

The Nacra 5.5 uni had the same history. The boat started out slower then a hobie 17 (74.0) and raced for several years at 74.5 It was very popular in CRAM as a one design and they did not turn in data.

Eventually they did turn in data and the number dropped to 69.5 or so.

But do not N17's sail ate the Alter quals events?

This is the underlying problem with returns based systems, people can abuse/manipulate them if they so wish; RYA PY drops boats out of the list if they do not file returns. Does USPN do the same?

nothing ever gets "dumped" from the Portsmouth ratings but they get a "bracket" in the system indicating that not enough data was available to establish a sound number. If the number in the portsmouth table looks like this: [64.1] then it is a reference number. Boats with brackets on their numbers are not permitted to compete in the area qualifiers for the US Sailing Championship.

Simon, for the record ANYONE can submit results to the DPN committee. Problem is very few submit results and I believe this more out of apathy than manipulation.

What insight do you have the DPN data is being abused and/or manipulated?

None; it's just I find it really odd that for example the N17 would be about 102ish under SCHRS (but without data I cannot be sure) yet it comes out at about 106 when you roughly convert the USPN to SCHRS(I used the F18 on both systems as the base).

We sail the the EU spec boat (heavier, smalller mainsail) on this (1.067 with a 19sqm kite, 1.073 with 17sqm kite). Something feels wrong somewhere.

We were doing OK sailing the EU spec 17 at 1.067 so I am concerned that I have not had a certificate form Nacra so I can confirm the rating for the N17.
Afterall there was a little agro at the last Carnac regatta about it; I would have HOPED Nacra EU would have fallen over themselves to provide the certificate to get a new rating for the boat.

Dear all, It seems a shame to drop this subject, I’ve got a question on this, I’ve got a A-class racing nationally under SCHRS and we get a lot of heat from other classes when I mention that the A does not rate well under SCHRS. Just to give you a bit of background on this, I used to race F18’s and have been a national champ a number of times in F18/ Tiger class before I moved across to the A. But since getting the A a few years back along with some other good sailors any A just cannot get to the top of the fleet at events when I know if I was back in my Tiger I would easily have been up there. The conditions have to be just perfect ( very light airs, flat water, very short courses) before an A-class can start to rate to SCHRS.

Thus my question is if I believe all the chat about that SCHRS is rating the A perfectly and I’m crap, why is it that the A-class is getting time under PY? For example in Australia the A and F18 race under Victoria Yardstick ( I know nothing about the Aus racing so I may be wrong on this, please correct me if need be) and it give the A time on the water, and that nation has some of the world’s best F18 and A class sailors racing against each other and there is no chat on the web complaining about their PY system. Am I missing something fundamental here?

Aus PY 2008 numbers http://www.vic.yachting.org.au/site/yachting/vic/downloads/Yardsticks07_08.pdf
Aus PY 2005 numbers http://www.vic.yachting.org.au/?Page=12596

The same story with the USA’s PY DPN numbers, the A is given time against the F18.
All the Best
Rob

I think its a problem schrs has rating singlehanders against two man boats .
SCHRS has a few other flaws and anomolous assumptions that I won't go into as schrs has no intention of ever addressing them .

But

I think an answer may lie ahead in that SCHRS can be used as a measurement system to identify a "starting " rating and then use the new PY system in uk to continualy update ratings there after (the new PY system in UK will allow clubs to compute race results and publish to PY system at same time, with the py system computer analysing in real time ) these two systems coupled together could iron out the anomolies that exist in SCHRS . alternatively Texcel ratings could be used as starting point .

SCHRS caters well for the majority , who in handicap racing tend towards favoured boats , whilst doing something like above could even the whole field .

As you may guess I'm a disgruntled minority , however heartened by the progress rating systems are making in uk .

The mono hull sailors are desperate to find a way of initially rating new or adapted boats into py ,

We are lucky in having two measurement formulas , SCHRS and Texcell to get ball rolling

Yes I too agree that a measurement system of some sort should be the starting point for DPN as well.

I'm looking into using SCHRS for some regattas and I'd like to get the good and bad of the system. Can you please PM me with the 'anomolous assumptions that you wouldn't go into'.

Thank you in advance.

I can tell you in the US under the PN system the A has a sweetheart rating. Mostly because the good sailors never race in the open classes. So the times never get turned in. I know I was sailing well one weekend and had a heck of a time beating them boat for boat against my I20. I think an A should rate right about the same as an F18, possibly faster. Definitely not slower.

Mike it really depends on the region.

The 'A' sailors in the southeast are pretty vocal about their rating against spin boats. If I announced that the Area D South elims will be scored using SCHRS I would get skinned alive.

Mark Smith finished second right in front of Bob Hodges at at the Area D South Elims in very light conditions, which is where the 'A' works its number to the fullest.

With the light amount of data that's turned in I really don't see the 'A' number going anywhere up or down.

Rob,

As stated below, under the AUS and US PY, the A has a very handy rating as it does not get raced much.

The A rates about the same as the F16 and they do OK against us on Handicap, and against other boat.
Chris was Flying at the Grafham open and that was hardly suitable wind for single handers such as the A.

(Remember each A needs to be measured to have a PUKKA SCHRS as the A class rules do NOT COUNTROL the same things as the SCHRS model uses to rate - Mast height and thus mainsail luff length being the main one).

The A DOES exel in the lighter stuff and so WILL struggle in the big stuff with such a high aspect ratio rig.



To answer Codblow (again) SCHRS has to make an assumption about crew weight, thus we use the worldwide average that is 75kg for an adult. Some will be lighter, some will be more.

We CANNOT implement a "actual crew weight" element as this would:

A, mean at EVERY EVENT and every race you have to weigh EVERYONE and re-calc the rating - it would be impossible.
B, Protests on weight of the crew anyone? - another nightmare
C, Inaccurate or differing scales? Had a big curry the night before?

We will not be implementing a "Crew weight" based rating element. End of story.

These two statements sum up the problem the USA has with using Portsmouth. If you can't generate a hundred races in each of the 4 wind speed categories with races of the major OD classes sailed by the top sailors in the class ... you won't be able to do anything better then more or less fair ratings.

Mike, the problem is not that OA's don't turn in data... they have no data to turn in.

Examples.

Tradewinds, 5 A cats and 12 N20's.... NO Portsmouth Data!

Area C Which has 12 N20's, 2 F18's and 40 A cats in region.... No Portsmouth Data from these boats. (only 4 boats competed)

On the Chesapeake, WRSC has 12 N20's and 15 A cats. We generated 1 regatta in 2008 of race results for Portsmouth. BUT... the top A class sailors finish top 20 nationally... the N20 sailors don't compete at nationals but usually don't finish better then mid pack historically... so the underlying Portsmouth assumption is just not valid. Result... even this data is pretty useless.

We did not have any other data comparing a 20 to an A cat around a standard course in 2008.

Toss in another new class which does not have OD nationals or much OD fleet racing and a second class which is very strong in a region but with a history of their popular single handed class rating trailing the true performance and it becomes very difficult to handicap designs with performance data.

Finally, with the advent of spinnakers... the time a boat is sailing down wind with 2x the sail area has decreased versus the time it goes upwind. Even worse the down wind speed is non linear, the spin sweat spot is in that 7 to 14 knot range. The A cat has a constant amount of Sail area. So it becomes very very difficult to rate the two against one another if the formula (SCHRS or Texel) and the race course don't match.
For Portsmouth, this fact makes data collection even more difficult. When race data are included from non traditional race courses or from non W L courses the statistical noise increases dramatically.

The A class, Hobie 14 and Hobie 17 have always been tough to rate against the sloop boats... it's much more difficult to rate them against the spin boats.

IMO, We should spend the money and get the Nacra F17 rated (in all of its configurations) so that SCHRSS and Texel have accurate data and then evaluate the rating table from a world wide perspective based on experience of the top sailors in the major classes. Decide if their is problem and then what to do about it.

Mark,
There were results of at least one race in 2008 turned into Darlene that included: N20, F18, NF17,F16, A-cat, Tornado (both with and without spin even) P-19, H-17 and I think a N5.8. I know because I was copied on that email and exchanged a few emails with Darlene. If you are truly in the know about such maters and did not see these results then there is a problem. Otherwise the data, though limited, is getting recorded.

The problem you've got there is that there is a drastic difference in performance potential throughout the wind range between a main-only and a main/jib/spin boat. If the A isn't flying a hull upwind, it will still probably get to the top of the course first, but the spinnakers are going to whiz right by going downhill. If the A can fly a hull upwind but not downwind, it's going to be pretty even. If the A can fly a hull up AND downwind - it's probably got a bit of an advantage.

It's evermore important to use wind specific ratings when racing such dissimilar boats because they behave so differently in the different wind strengths. The wind corrected ratings between N20/F18/A-cat seem to support this performance characteristic.

And Another Thing to Overcome Common Logic:
Whilst the spin boats are flying giant spinnakers while the A-cats are still using their tiny little mains only, the lets say "Alter Cup Area D" course can (randomly) be an even number of legs or odd. Usually, spin boats catch the A cats near the finish line because of EVEN-numbered legs. NOW- Guess what happens if there are an ODD number of legs: A-cats smoke 'em, and the F18 guys cry, moan and complain.

Totally agree, we need to reinstate the downwind start and sail leeward/windward for one and a half lap

This spis are hardly giant
A catters are free to add a spi, but they (rightly) choose not to.

Don't be a hater.

Yes please; I've been waiting 9 months now...............

Here are the results from the Area L Alter Qualifier from September of 2008. Including times and wind conditions.
Unfortunately the winds were light most of the time. But when it did pick up to 8-10 a couple of times the F18s began to show thier stuff

Mostly there were A Cats and F18s there. We had 17 participants.

Check out the link it will show the info.
BBOD Regatta 2008

The wind speed ratings group Beaufort 2 with Beaufort 3.
This decision was made years ago when boats like the Hobie 16, 117 and 18 behaved pretty much alike through the wind ranges. It was WAY before Light weight boats like the A Class and Spinnaker boats were popular.

One issue that you highlight is how non linear the actual performance is for these two boats in this wind range.

What is needed for a better yardstick table is separate ratings for Beaufort 2 from Beaufort 3. This is tough because you need 100 races of data turned in from top of the fleet sailors racing each other in the wind ranges.

Where did you get that "100" figure? Or were you exaggerating to make a point?

The PN software is written in Fortran. A near dead language 25 years ago... (remember the y2K death watch) it has a limit to the number of variables it can handle.

All data is pre screened for being an outlier... IE the computed rating is 10 % faster or slower then the current rating... MIND YOU... the data is computed in the wind speed reported for the race.

The number of ratings used to calculate the rating is 100 data points in EACH wind speed. (If you did not roll in new data and kick out old data... the average would never change.)

Beaufort 2 data is tabulated separately from Beaufort 3 data and if memory serves for each wind speed but so far... the data don't reflect the performance difference and so 2 and 3 are lumped together. Again... it's not just A class and F18's to consider....the Hobie 16, 17 and 18 performance are still not going to vary much over the B 2-3 range.

This analysis was done a couple of years ago... So Darline may have more data with light boats, spin boats and secondary yardstick boats to evaluate. It may have changed since then.... but since the Area L results only contribute 6 or 7 data points....AND the race did not have a well sailed secondary yardstick boat.... eg a hobie 16 Its tough!

The DPN rating is weighted to the B4 rating and is some formula of the 4 wind ratings.... (new boats B4 = DPN)

So... if you don't include an accurate wind speed for the race then your data becomes difficult to use.

Quote - Scooby

"[/quote]" To answer Codblow (again) SCHRS has to make an assumption about crew weight, thus we use the worldwide average that is 75kg for an adult. Some will be lighter, some will be more.

We CANNOT implement a "actual crew weight" element as this would:

A, mean at EVERY EVENT and every race you have to weigh EVERYONE and re-calc the rating - it would be impossible.
B, Protests on weight of the crew anyone? - another nightmare
C, Inaccurate or differing scales? Had a big curry the night before?

We will not be implementing a "Crew weight" based rating element. End of story. [/quote]"


Scooby I didn't ask any questions , nor sought any answers from you .

I'm well aware as I said of SCHRS stance on anomalies , and don't need things rammed down my throat as if I'm some sorta half wit !!!

SCHRS is your rule , your running it , good , I can live with that .(and thanks for doing it too - schrs has certainly improved cat racing )

Any measurement rule created will have anomolies in it - thats why you will always get bandits and dogs , whatever you do .just look at monohull racing and the shed load of money spent on rating rules the computing power put into it and decades of developement .

All I was trying to say , with the new RYA PY system we have a unique opportunity to merge the systems together which could iron these things out .

I'm not talking of weight of sailors here.

But it is concievable that as time progresses and the rya py improved and quicker database develops , we could - shock , horror, god forbid , look at personal handicaps , for club racing , we all know what a can o worms in the past this has been and a crock of sh~t , but, could be an answer to dismal turnouts in club racing throughout uk.

goes without saying champion ship and event racing would still be on boat rating under whatever system

(can't believe I just said that !)
Still look at golf , works for them ,

I thought it was actually Cobal that it was written in..but very similar regardless (I used to program both).

It definitely needs updating and the statistical analysis could use some advancement. I have a lot of thoughts regarding this but will not waste my effort if you guys see fit to kill it.

Please no! Golf handicaps are easily manipulated and often are! Let's not speak of this again.

After taking a looking at your avatar I would rather race boats too

Hey- Wouter is an Engineer. Lets hire him to Fix the Fortran!
MWHHHaaaaa!

Flip flopping my way back out from under a rock, At least we can agree that there needs to be a solution between the two major systems, Thus measure a boat using SCHRS and tweak out any bandits or up any murdered boats with a PY fudge factor. The two major problems then are is who controls the fudge factors and how to you collect all the global PY data.

One question on the SCHRS rule, is it designed as a windward/ leeward, circular random, Olympic or Liner random course?

And why is US sailing not promoting ISAF's SCHRS, and do we have a global cat association?

To reiterate an earlier post, US SAILING administers the Portsmouth Yard Stick along with several other ratings systems for monohulls. The Portsmouth Committee has that continuing task, and Darline Hobock is the chair. Bob Curry is a member-at-large on that committee.

The ISAF Multihull Commission was approached last October about possibly taking over the administration of SCHRS, but the issue was not decided since a great deal more discussion is needed before making a decision.

The US Multihull Council has accepted an agenda item for the Spring meeting in Denver this March to discuss the rising tide of complaints about the Portsmouth ratings of small catamarans, and hear suggestions on how to improve things or make changes for the better.

"The US Multihull Council has accepted an agenda item for the Spring meeting in Denver . .. ." Glad to hear it. Addressing concerns is always positive. If a solution proves unattainable, at least you tried.