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I read the forum article on PHRFs and understand the basics of how it works.

I am crewing on a club member's boat. We have a wide range of racers, but our CS30 consistently comes in third in every single race. The skipper has asked about PHRFs on rival boats, and thinks they may be out of whack.

I know that the first answer is going to be: 'if you have reason to doubt a PHRF, talk to your race captain and confirm the rating on that boat'. Well, that only gets you so far. The onus is on a skipper to get a PHRF on their boat, so once they've done that, who is to say otherwise?

I'd like to see for myself what the data is saying.

I am wondering if there is a way of examining the data and determining if the PHRFs are sensical. It seems to me that, over many races, you should be able to say some things about the boats, the crew and the PHRFs.

For example: if the actual times over the finish line vary by a large amount, yet the order of winners is the same (after PHRF is factored), that would strongly point to the PHRF factor overwhelming any racing skill.

Say ten boats have pre-PHRF times that span a range of a mere 30 seconds, yet the post-PHRF times span a range of 60 seconds or more, you'd get "corrections" that are larger than the individual differences. That would indicate that's something's not right.
 

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Dave,

I am not sure what you are asking. PHRF by its nature is a mixture of objective and subjective measures. You can ask your local committee to re-evaluate your rating, but that generally doesn't do much unless you can show evidence that there is a real issue.

As for your examples...

1) the fact that boats finish in a different order than they wind up in is a handicap system working as intended.

2) phrf is time on distance, so I am not sure what you are getting at.

The concept is that if two boats have perfect starts, sail perfect races, and have perfect equipment phrf would result in a tie regardless of their finish times.
 

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No Dave, the race results would indicate that some boats were sailed better than others. I am assuming you are complaining about “production” boats and not one-off racers. The PHRF regression formula only “equalizes” basic dimensional parameters. It does not rate the condition of the sails, rigging, crew skills or the type of beer carried on board. PHRF is not a golf handicap. You need to give me some more information such as where are you racing, what PHRF committee you are using, link to your race results and what type are the competitor’s boats? Here is the regression formula:

R' = 610-8.36*(SA/Disp^.333)+0.0000511*(SA^2)-55*(P/(J+E)) -30.8*(LWL^.5)-602*(DR^2/SA)

where SA= .5*(I*J)+.5*(P*E)

I ran your numbers through the formula and I get 147. Note that depending upon your regional conditions, your PHRF committee may “tweak” the formula. For example, they may “tweak” to give a heavy displacement boat some more time if their prevailing conditions are “light”. My experience with PHRF (I was National Measurer for the Catalina 34 fleet at one time) is they apply their formula equally across all production boats. It is only when you either heavily modify a production boat (like stripping out the interior) or if you have a “one off” boat do they get out their tape measures and scales.
 

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Dave-
A PHRF rating will never be fair, or correct, or exact. It is at best a way to lumping similar beasts together. If you dig around online you will probably be able to find the different ratings applied to that "same" boat in each PHRF fleet in the country at which point your first question is probably why all the ratings are different if the boat is the same.

Well, PHRF blithely ignores the fact that there are different wind conditions in different parts of the country, which the local fleets adjust for. And it presumes perfect triangle courses, which many courses often are not. It is also a moving target, and you will find ratings adjusted typically in each of the first three years that a certain boat has been regularly competing--if there have been any regular competitors--to reflect how it has performed.

If a local skipper has been a duffer with old sails and consistently run slower than the rating, it may be (unfairly to everyone else) adjusted down. Then someone else comes along, a real master with new sails, and all of a sudden he's beating the ratings. Unfair again.

That's just the way it goes. PHRF isn't fair, it isn't perfect, it has limited abilities to be locally corrected and adjusted over the long term. For the folks who don't like it, there's not much to be gained by complaining. Appealing, if there's a good reason, yes. But basically if you don't like it? You race one-design or some other system, where the rules may be "fairer" or clearer.

That's just the way it is.

Or you stick to PHRF, don't worry about the silverware, and just concentrate on finding ways to sail faster. I know guys who have a 40-gallon fuel tank, who will only put in four or five gallons because "that's enough for today" and anything more is just going to slow down the boat. The winners? Pretty much are all thinking that way, and not just about weight.
 

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Some regions have modified PHRF to 'time on time' in which case corrected times can be longer than elapsed times and the real time spread can widen.. IIRC correctly the time-on-time factor centered around a PHRF of 120secs/mile, with a time-on-time factor of 1.0; boats 'slower' had their ET reduced, but boats faster ended up with CTs longer than ETs... Maybe that's what the OP's group is using and what he's seeing..

It's been a while so it may have changed or I may be mis remembering.....

In any event it's an imperfect system but one that seems to generally work for the majority. There are appeal avenues if you feel your rating, or a competitors, is wrong in either direction.
 

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You will find in many fleets that the guys that are winning the most have a boat the sails to or better then it's rating. if you want to win then sail on one of those boats. the boats that can win will have the pick of the best crew in the area. good crew want to sail on good boats.good crew makes them even faster. And so the rich still get richer, at least in the number of pickle dishes they have won.
 

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Sure it might not be right in all cases and I can cite cases of boats that were screwed by bad ratings, but I am more often shocked at how well PHRF works, all things considered. For example, in pursuit races (with staggered starts based on PHRF ratings) it is amazing how many boats will hit the finish line at roughly the same time, just as intended. When I started racing, I thought my rating wasn't fair. Then I raced a lot and raced some more, replaced my ragged sails, cleaned my bottom on a regular basis and had the good fortune to get some top-notch sailors to race with me. Next thing you know, people were complaining about my rating. At the risk of generalizing, sometimes I think that those who complain about their ratings the most many times aren't doing that much to improve their performance, e.g., racing a lot, taking lessons, cleaning their bottoms and springing for new sails.
 

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Any idiot can buy a boat, although, when the boat won't move without a lot of effort and those sail things, I suppose it changes the class of idiot somewhat?(G)

But when any novice gets the idea that racing might be fun, the odds are the local racing is PHRF and all they know is they're racing. Folks just have no idea how it works or how it is applied. I missed the week in kindergarden when they explained how life just isn't fair, deal with it.

So you do the best you can, and worry about whether you are doing everything you can to get boatspeed, regardless of what other boats and crews are doing.

"Starboard!" works on the buffet line, but is worthless on taxis.
 

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TOT in PHRF has THREE, yes three wind speed factors, which will change the 1 or zero boat if you will. In the 0-7 mph the 1 boat is around 140-150 IIRC, I figured this all out using a rating computer program once. 8-15mph is about 80-90 or so, then 15+ is around 20-40, with TOD being a 0 rated boat. BUT, as I am reading etc, when phrf started out, no one thought any one would ever have a rating less than 0. Yet locally a number of the sleds, ie a TP52, Santa Cruz70's that would be in the -50 to -100 range. Or Bob Perry's Icon is in the same area of phrf ratings too.

Marty
 

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Dave,

I am not sure what you are asking. PHRF by its nature is a mixture of objective and subjective measures. You can ask your local committee to re-evaluate your rating, but that generally doesn't do much unless you can show evidence that there is a real issue.

As for your examples...

1) the fact that boats finish in a different order than they wind up in is a handicap system working as intended.

2) phrf is time on distance, so I am not sure what you are getting at.

The concept is that if two boats have perfect starts, sail perfect races, and have perfect equipment phrf would result in a tie regardless of their finish times.
Many PHRF fleets use time on time.
 

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We use PHRF TOT in our fleet. We find it helps to tighten up the competition because how long a race takes varies according to how much wind there is. Having the handicap depend solely on the distance of the race favors the faster boats that can finish before the wind dies. Putting the time it takes into the equation evens the playing field a bit.

Having PHRF ratings for the same boat vary from region to region makes sense because a heavy boat's results will tend to be better in a high-wind region (e.g. San Francisco or Narragansett Bays) than they would be in a light-air venue (e.g. San Diego or Long Island Sound). Rating systems that ignore local conditions and furnish only one "worldwide" handicap number are essentially saying that windspeed doesn't affect boat performance. While not perfect, PHRF seems to work well enough for most of the races in the U.S.
 
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