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Seeking input on PHRF


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Rehabilitated

 

Think you will find IRC is the more popular of the measurement handicaps in English speaking countries, ORC more popular in Europe excluding France and then of course there's ORR and HPR in the United States.

 

Whilst patterns of use change slightly from year to year, neither IRC nor ORC are becoming dominant over the other and each have similar levels of active certificates.

 

IRC is the preferred measurement handicap in New Zealand, primarily because it's probably the handicap that will be used if a New Zealand boat races offshore, eg, to do a Sydney Hobart, Hamilton Island or Fastnet.

 

That said, both are available in New Zealand, costs from memory are similar.  Don't think ISAF push any one handicap over another, they pretty much leave national authorities to decide what's appropriate for themselves, which is how it should be.

 

Whether either would be appropriate for club local racing is pretty debatable, myself I would say that forcing clubs to use either for their local races with the costs that it would entail would be one of the quicker ways of killing off that level of racing.

 

At a slightly more serious level of racing, coastal type stuff, there is interest in some areas in further encouraging use of measurement based handicapping.

 

Whether that comes to pass or not is really the choice of boat owners.  PHRF is currently the default for a variety of reasons, it'd be good to see more of IRC, whether it's in anyones interests to complicate things by adding in a third system is pretty debatable. 

 

Both IRC and ORC have strengths and weaknesses, myself I'm to be convinced that ORC is so much better than IRC that the latter should be ditched in favour of it.

 

 

 The posting above by GUEST is ISAF wording they are promoting it / pushing it [ READ THEIR WORDING ] and the USA have joined the revolution towards it. Quoting Europe is a no argument. The argument is decided on how many are unhappy with the present flawed system within each ZONE..

 

The system once a DATA model  is established is not expensive. What is expensive or not expensive  [ not expensive if a volunteer expert compiles the data development model or another model producing organisation.  ]

 

 QUESTION   What price do you put on FAIRNESS ? DOES IT NEED TO BE PRICED ?

 

and YNZ avoided giving an answer. WHY YNZ ?

 

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CIORC have largely working with PHRF lately, however they have had discussions about engaging with the multi fleets. YNZ will make an approach to the Multihull YC to see if someone would like to come

The posting above by GUEST is ISAF wording they are promoting it / pushing it [ READ THEIR WORDING ] and the USA have joined the revolution towards it. Quoting Europe is a no argument. The argument is

That's no excuse if their is a better and fairer system.   OC

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markm

my  question was only part answered maybe the other part is to hard to answer given the gap in the difference of handicaps between  IRC and PHRF

i am only referring to IRC yachts  racing also with a PHRF  

what is happening IRC yacht can win it s division on IRC and get nowhere on PHRF and another yacht with a IRC rating can get last on IRC yet win on PHRF all in the same race

surely this gap in handicaps between IRC and PHRF should be looked at and bring the PHRF closer to IRC

i don't know what the answer is BUT it does need looking at

another thing with IRC yachts they are restricted on the number of spinnakers they can race with where PHRF are not

at the end of the day all that is required is a system that gives every yacht a chance which I believe IRC does

 

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CIORC have largely working with PHRF lately, however they have had discussions about engaging with the multi fleets. YNZ will make an approach to the Multihull YC to see if someone would like to come to an upcoming meeting.

 That's no excuse if their is a better and fairer system.

 

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Hello L_AKL,

 

Apologies, I was a little hesitant to post much for a couple of reasons.

 

First, and I must stress not at all related to your post, my personal opinion was that some of the posting on the thread was pushing an agenda not at all related to the merits, or not, of PHRF and not related to IRC or ORC either.

 

Happy to be involved in discussions related to various handicap options and encourage others to express views, positive or otherwise on the same but the other stuff, I just disagree with the approach.  Think there are better ways to make a difference.

 

The other reason is that whilst I wasn't sure I agreed with your contention on variances in PHRF and IRC results, rather than saying anything I wanted to do my research, confirm or change my view and put together a post which included some basis behind what I thought.

 

Okay, first question on why PHRF can yield significantly different results to IRC.

There's likely a myriad but I'll comment on three that come to mind.

 

First, there's a performance component to the calculation of the handicap which does not exist in IRC.  In other words, using past history, the handicap is partly influenced by the profficiency of the crew as well as the capability of the boat.  That will sometimes yield different results. 

 

PHRF's objectives are slightly different to IRC and the PHRF group believes it appropriate to allow past performance to partially influence the handicap as a means of meeting those objectives.  You will note with the most recent set of changes, one implied objective of the changes is to allow better control of the influence that past performance has.

 

In the survey of a couple of years back, one question covered the area of how much influence performance should have.  About half of the respondents indicated they were either happy or thought more to be appropriate, the other half indicated less or none appropriate.  In the end, the decision was to tighten it slightly.

 

Second, PHRF assessment on a boats capability is not always in agreement with IRC.  You've stated you believe IRC gives all boats a chance and certainly implied the PHRF has it wrong. 

 

My personal view is different.  For the record, my view is IRC does a very good job sometimes, a reasonable job as often as not and a pretty poor job with maybe 20% or so of the kiwi fleet. 

 

I could list examples and am happy to do so, but highlighting what I believe to be IRC shortcomings isn't my objective and won't achieve much in my view.  Anyway, PHRF attempts to fill that gap, perhaps successfully, perhaps not.  Again, different assessment will yield different result.

 

Third there is perception.  By way of example, a fleet of 12, five with IRC ratings and all 12 with PHRF.  A boat places 3rd on IRC, 6th on PHRF.  As a competitor, 3rd feels one hell of a lot better than 6th.  The reality here is that 3rd is mid point, 6th is a touch above mid point so the boat did very slightly better on PHRF.  Third still feels better to me, as I said, a perception thing.

 

 

Okay, I'm mentioned research at the start, the research I had in mind was on the lines of how often does PHRF gives substantially different results to IRC, and although not asked, a second question, is that likely to change with this years changes in PHRF.

 

Data I'm using is most recent cert I know of for any boat in New Zealand that has had an IRC certificate (246 boats) and all racing since 2014 where a boat also had a PHRF certificate (current at time of race) and their were at least four boats with both.

 

I could have limited it to only IRC certs issued since 2014 (60 boats) but that really cuts the numbers down too much to be usable.

 

Likewise, I've only included racing under inshore PHRF, having only one IRC number and one PHRF number is a lot easier than three and it covered 85% of possible results.

 

 

334 races, average 6.6 boats per race
37.1% score same pplacing, IRC and PHRF
31.9%, one place different
15.0%, 3 or more places different
1.35%, (9 times) in a race a boat swapped first to last or last to first, only once in a major event

Whether this represents major differences between how boats place under PHRF and IRC is personal opinion.  Myself it looks reasonably close most of the time to me and I don't see the first to last thing as a big problem but I'm sure others will have differing opinions.

 

As has been commented before, one aspect of this years PHRF changes has been to tighten up the extent to which PHRF is affected by performance.  Also, LA has asked about PHRF getting closer to IRC so I ran some projections using the data as above, but scoring what the PHRF system will now allocate to boats instead of the PHRF at the time of the race.

 

252 races, average 5.9 boats per race
43.9% score same pplacing, IRC and PHRF
35.4%, one place different
8.2%, 3 or more places different
1.39%, (7 times) in a race a boat swapped first to last or last to first

 

Some of this change is just due to there being less data, if on average there are fewer boats in a race, then the odds of placings being the same under both scoring systems goes up.  As best as I can calculate, about 60% is due to that and about 40% because PHRF numbers align more closely with IRC.

 

So to answer LA's question on what can be done to make PHRF more like IRC, we think those changes have been made and we think it will show through this season.

 

But also to stress, we do not want PHRF to be the same as IRC, we'd just ditch PHRF if that was what we wanted.  Differences will remain for reasons outlined earlier. 

 

In some respects, the question needs to be asked if PHRF is too close to IRC rather than not close enough.

 

Finally covering off comments on IRC sail restrictions versus none in PHRF.  Think IRC may also have a few other restrictions, perhaps crew numbers or weight and maybe one or two others.

 

At a pragmatic level, because PHRF has a performance component, if you've been racing under dual sscoring,, any disadvantage incurred due to the IRC limitations will be included in the performance component so you will be under no disadvantage, your PHRF self adjusts to account for it.

 

But have to ask, why is it the fault of PHRF that IRC limits the sails you can carry.  You could argue that crew number/weight limits and kite number limitations are a loophole to be exploited in PHRF and you're right in theory.  No ones telling us though it's such a big loophole they won't have anything to do with PHRF so I can't really see it as an issue that needs fixing.

 

I think I've answered everything, let's know if not.  We won't agree on everything I'm sure but done my best to explain.

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So after the changes how much of a boats PHRF number is based on the assorted inputs?

 

It seems PHRF numbers are based on 3 inputs. One being measurements, one the committees guess and the 3rd being a small splash of history, if you have one. In percentage terms how much does each one of the inputs count to the final number?

 

Just thinking I have no history nor can I change any of the committees assumptions but I can fiddle with measurements. Basically can I now optimise my boat for PHRF like you can other systems?

 

One other quickie, if a boat can very easily and quickly swap configurations to a significant degree, how do you work out which configuration to put on your PHRF form? I ask as I enquired and to find you can only have one PHRF number.

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markm

thanks for your reply did answer some queries, but as i have set lawless  up for IRC which i believe is the  fairer  handicap system, which i am more than happy with

in the pass i have had problems with the way in which PHRF  has been run for example ,this happened in my case where a third party was able to get the PHRF rating changed even as they were not a boat owner and this was on the eve of a major race,

which i with drew from as YNZ were not prepared to a meeting to discuss on the morning of the race,  because of this i have a problem with PHRF and the way it can be easily adjusted with no real reason

 

i would hope that a 3rd  party cannot do this now

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Mark thanks for your response, no handicapping system is perfect but the underlying philosophy needs to be clear so that owners understand what you are trying to achieve. 

 

 

First, there's a performance component to the calculation of the handicap which does not exist in IRC.  In other words, using past history, the handicap is partly influenced by the profficiency of the crew as well as the capability of the boat.  That will sometimes yield different results. 

 

PHRF's objectives are slightly different to IRC and the PHRF group believes it appropriate to allow past performance to partially influence the handicap as a means of meeting those objectives.  You will note with the most recent set of changes, one implied objective of the changes is to allow better control of the influence that past performance has.

 

In the survey of a couple of years back, one question covered the area of how much influence performance should have.  About half of the respondents indicated they were either happy or thought more to be appropriate, the other half indicated less or none appropriate.  In the end, the decision was to tighten it slightly.

 

I am not that affected by PHRF as I only use it for the SSANZ series and feel that it's yet another fee to pay and grudgingly accept it as my lot if I want a chance of glory on the podium. It gives a reasonable semblance of order in that series, I suspect most of the boats that enter would not use their PHRF very often elsewhere.

 

If I had invested many hundred of thousands into a top class racing boat and crew I would choose IRC as it reflects the boats performance and effectively pits crew against crew whereas in PHRF a top crew that is sailing 100% can be beaten by a crew that improves from 70% to 80%. That is more like club racing but without the weekly updating that a good club handicapper provides.

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Km, there's some blurble that goes forever on the YNZ site but I'll try to cover the bits I think relevant to what you've asked, whilst probably still going forever.

 

Influences on your number.

 

Really there's only two influences, committee opinion on your design and performance history.  Declared measurements do influence the handicap but only because they influence the committee opinion.  There's four in the group and the other three are pretty sorted out people who have a pretty good handle on a lot of the racing fleet. 

 

Measurements in part tell the committee what you are and are in part a mechanism to enforce declaration of changes.  We try to be pragmatic, we know for example that a weight declaration for Black Panthers largely going to be a guess, a just launched race boat though should know their weight to the nearest 1% and that too we expect.  If though you're a 930 and want to be treated as 20% heavier than class, well that you need to prove, we aren't going to take your word for it.

 

Optimisation, the quick answer as the above partly implies is dont bother.  Our aim in the design assessment part of the process is to have a neutral bias towards change.  We won't be perfect on the design assessment, we are hopefully at least reasonable most of the time. 

 

Subjective judgement is not ideal, but we think one of it's benefits is that it is better when it comes to judging things like the effect of a code zero on overall performance.

 

How much does performance influence your handicap?

 

In almost all cases, we set a design number for a boat and from that determine a range.  At the moment the range is + or - 2.25% of the design number.  In English, if we think you're a 0.800 boat, the range will be from 0.782 to 0.818.  If you have no racing, you'll be on 0.809 to start, being the 75% point in the range. 

 

We also limit the influence that one race can have, no more than 1/5 of the range for the boat.  so using the previous example, if you've only sailed three races, your handicap won't be lower than 0.789 and not higher than 0.811.  Most people will have a lower handicap if they put some races together, that's intentional, look on it as an incentive to participate in racing.

 

Different configuration and modifications.

When we receive a modification, one of the things we will determine is whether we think it's a major change or not.

If it's a major change, something of the lines of a new keel and such, we're going to reassess you from scratch and set you so we ignore performance history from prior to that date.

Most changes though we will make a judgement call on how much to increase your handicap, bump it up and flag you as 'manually changed' for the next three to six months.  At that point, we'll relook at your performance numbers and more often than not, let to automatic calculation process take over.  Not always, if there's more of a change than we were expecting, we may keep that process manual.

 

As those silly enough to be still paying attention may spot, there is a bit of a benefit for modified boats there.  We don't think it's big, but we do have the option to set the point from which we consider performance history for each boat and we'll use it where we think it appropriate to keep racing fair.

 

Basically though, if you want to buy a masthead kite or code zero or in some other way make your boat quicker, we don't want PHRF to be a reason not to do it.  Likewise, we don't want people 'slowing' their boats down by say declaring only a fractional kite or a #2 headsail because they think they can get some sort of advantage.  Certainly for myself, the latter should be discouraged.

 

It's pretty difficult though for a system that uses performance as a component to handle multiple configurations concurrently.  Like other systems, we're very much single configuration. 

 

If someone particularly thinks they have a need for this, call and discuss and if we agree, we'll try to set something up manually to handle it.  It won't save you money though, it's still a fee to change and in most cases, changing a configuration for a specific event will not give you as much benefit as you would get racing under one configuration all the time.

 

Likewise, we don't want to encourage people requesting last minute configuration changes based on forecasts for a particular event.

 

Generally, we'll do changes in under 15 working days but people should note from the website that we request 15 working days to process configuration changes.  Part of this is to prevent optimisation for a forecast so please keep in mind, particularly as there are only 14 working days to coastal.

 

Think I got everything KM, probably in more detail than almost everyone wants.

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Thanks fella, nice answer. The optimise for PHRF was a hypothetical obviously as I also don't see great advantage unless you do the same thing all the time in which case you'd tune your vessel to that anyway.

 

The change of configuration is a issue though. With my boat I've tried, and I think may have succeeded to a fair degree, to get her to a point where I can change modes for the wildly differing racing I'm wanting to do. That comes with wildly different configurations, displacements, sail carrying ability and many other things. It's a fun project and I'm enjoying it, bar the carbon splinter in my finger from this morning.

 

I am not going to be ringing YNZ every Friday saying I'll be in so-in-so mode this weekend. I don't want that and I seriously doubt they do either. I'll figure something out.

 

Right back to my hatch construction, I should be able to de-bag now. It's a little exciting thinking about what's under all that peel ply. I may have the 1st ever Ross 930 companionway hatch that doesn't leak :D

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