Les,
Data is not wrong, it is data
The data will not be wrong but the processing method or the intepretation of this data may very well be. My argument focusses on the latter part. Here Yardstick systems have a well documented fundamental flaw. Texel uses what is called a parameter driven/describing fucntion system identification method. Under a certain set of conditions it can be proven that this later methode is more accurate and less sensitive to outliers then a straight forward statistical approach (like yardsticks are).
It will be far to complex to get into detail. I will try to think up a few examples to make thing clearer. If anyone is really interested then I advice then to pick up some text books on system identification.
Portsmouth is reflection of the data.
That is not entirely the case. It is more an intepration of what the data is showing. Apply a different processing method (in developping the ratings) and you'll can get a different intepretation (reflection).
however, I believe that the US catamaran racing fleets are best served by using Portsmouth in its entirety
This is a different topic all together. This is a seperate issue from whether the used rating system is more fair (accurate) then another. This one is best in serving the needs of a given community is not hard science while accuracy is.
While I absolutely certain of the superiority of Texel 2005 in the area of accuracy, based on hard science, I can't be that in the way of which system serves which community best. We should take care to keep these two issues apart.
And you said “US PN have us 4% to 5% slower then the F18's.” Portsmouth is reflection of the data. Data is not wrong, it is data. As more sailors race F16 in the US (admittedly, a VERY small number so far) true capability of the F16 and F18 will be reflected in the data. For the time being, the data says that the F16 is slower than the F18, and the F16 1-up and F16 2-up are not equal. This is only fair to those who sail those boats.
I know this to be nonsense. The F16 rating hasn't been converging under US PN for years now, despite the gulfport guys and gals sending in all their data. Some would say that that is because the Taipans+spi are really not that fast. But that would be really funny as the Australian yardstick system VYC is rating the Australian Taipans WITHOUT a spi faster as the US Taipans WITH a spi (relative to the F18's). They can't both be right at the same time. This is actually a great example of how much offset can be propagated into yardstick ratings.
When sailing under US PN I would have been in direct competition for the title of club champion and I'm really not that good as sailor, we have a few ex European and World champions racing in our club races. The US PN ratings for F16's are seriously off the mark and I know that from personal experience.
I'm also very happy that Chuck is putting up wagers that he and his wife will beat F18's to the beach, no use of peachy PN ratings. In the first such comparison they actually put deed to claim and finished ahead on elapsed time.
Gary Maskiel and others are doing the same. I'm sorry to say but the US PN rating for F16's is just wrong. But then again it is wrong to the advantage to the F16 owners so we will not complain to hard about it.
Regards,
Wouter
