Print Page | Close Window

Dynamic ratings from Sailracer.

Printed From: Yachts and Yachting Online
Category: Dinghy classes
Forum Name: Dinghy development
Forum Discription: The latest moves in the dinghy market
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=12946
Printed Date: 28 Mar 24 at 7:00pm
Software Version: Web Wiz Forums 9.665y - http://www.webwizforums.com


Topic: Dynamic ratings from Sailracer.
Posted By: Do Different
Subject: Dynamic ratings from Sailracer.
Date Posted: 29 Dec 17 at 11:39am
http://sailracer.org/ResultsEntry/Article/Dynamic%20GPS%20Handicapping

Something to chew on for the New Year.

I have to take my hat off to the effort this lot are putting in. I guess so long you know what you are signing into it is hard to fault the notion of nobody copping a stinker day.

For my part at home I quite like the lottery variable conditions impart to Club handicap racing; "every dog has his day".  I did the first Sailracer Weymouth and would be ok to give this a go if I was doing another one. Truth is I have simply enjoyed getting involved in a few bigger events and will always judge myself against the same or similar boats, final numbers are not without value but I'll not shed too many tears or delude myself.
  



Replies:
Posted By: Sam.Spoons
Date Posted: 29 Dec 17 at 12:00pm
Interesting point about the old/new boat conundrum, that an old DIY Solo could be expected to be 6% slower than a new FRP one. But they don't take into account that the new boat is inevitably sailed by someone much more motivated/ambitious than the old which probably makes more than 6% difference....... The only way to truly calculate the difference age makes is to have both boats sailed by top sailors........

-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: Dougaldog
Date Posted: 29 Dec 17 at 1:22pm
Sam - this is pretty much the territory covered recently in "I am not a number". Much of the leg work has been done already and the 4-6% difference took CSF into account - so in reality, the margin could actually be larger.

In the end, it almost comes down to a philosophical debate: what do you want the PY system to do? Do you strive for the basic, non-interventionist way of thinking - as Do Different said, this allows every dog to have his day. Or,   do you use a clever systems approach, so that whatever the conditions, there is as level a playing field as can be practically made possible.

I'm now in the camp of thinking that it is no longer science fiction to create a better, more intelligent way of doing things, but at the same time, I accept that the views expressed in the debate that followed the publication of "I am not a Number" indicate that this remains currently a minority view.

D


-------------
Dougal H


Posted By: 423zero
Date Posted: 29 Dec 17 at 6:50pm
To make Handicap racing about the Helm or Helm/crew, regardless of what they are sailing or weather conditions.


Posted By: Guests
Date Posted: 29 Dec 17 at 6:54pm
The irony is the author only knows Dobson should be doing better because of results from class racing. 

Making the handicaps 'dynamic' I think is missing two points. 
1) The numbers are still generated from performances which are the product of boat and crew. No amount of statistics up-speak will gloss over the fact that they are inseparable and without a clear methodology the talk of 'vast amounts of data' , 'standard deviation and confidence interval' is just massaging numbers until the names the author thinks should be winning, are winning. 
2) I don't like the result not being obvious on the water. Corrected time handicapping is bad enough in this regard, but at least the maths are simple enough that you can estimate in your head and understand the calculation to check it ashore. No point being more accurate if people can't understand and believe it.  
  



Posted By: ian.r.mcdonald
Date Posted: 29 Dec 17 at 8:43pm
Originally posted by Sam.Spoons

Interesting point about the old/new boat conundrum, that an old DIY Solo could be expected to be 6% slower than a new FRP one. But they don't take into account that the new boat is inevitably sailed by someone much more motivated/ambitious than the old which probably makes more than 6% difference....... The only way to truly calculate the difference age makes is to have both boats sailed by top sailors........


I think you are right, the 6% difference may well apply when comparing an original Solo sailed against a brand new boat with the pro sailor in one and the 60 year old ( thats me!) in the other. But the concept that on flat water a double floored and modern rigged wooden Solo is significantly slower is incorrect. Is the next plan to split each class into 3 or 4 speed groups?


Posted By: 423zero
Date Posted: 29 Dec 17 at 9:05pm
I think Merlin class and Finn class do this already, new handicap and classic handicap.


Posted By: ian.r.mcdonald
Date Posted: 29 Dec 17 at 9:11pm
having rubbished the concept, I have to own up that my club has a different handicap for old and new Solo!


Posted By: Rupert
Date Posted: 29 Dec 17 at 9:15pm
Hmmm, I think that firstly they are overly congratulatory to themselves when discussing the GL handicaps. Secondly, I feel they miss the point of why people handicap race at clubs. It is a competitive passtime. The idea of not knowing what handicap you'll be given until a computer decides, after the event, will turn people off in droves. Pursuit races will have to have start times decided by divination.

At one point, it is mentioned that boats plane at different wind strengths. Presumably, we will all need to be weighed, too? Pretty sure I'd start planing in a Phantom well before the average Phantom sailor, and in a Topper well after the average Topper sailor.

-------------
Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686


Posted By: Sam.Spoons
Date Posted: 29 Dec 17 at 9:24pm
And I think that is fair enough but the point should be that the handicap reflects the boat not the sailor and the GL system does at least address this to a point by culling the back half of the results from the stats. Beyond that I think the 'every dog has it's day' approach has merits. It's good to see different handicaps for the different versions of classes that have seen major changes in performance and a small, simple 'age allowance' for those which have remained substantially 'one design' (Enterprise say) with only small incremental improvements would be nice too.

The ultimate and to the GPS based handicap system would be to allocate different handicaps on a leg by leg basis according to wind strength, sea state and direction Confused which would make the results incomprehensible to all. I agree with mozzy, I like that I can make an educated guess where I stand during the race.......


-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: 423zero
Date Posted: 29 Dec 17 at 9:49pm
yes, weighed and then the matching PY for your particular chosen class, Toppers minimum and maximum weight range etc.
Class and handicap racing, then it will be your results (personal handicap), all the way through race everyone constantly monitored.
423zero, boat 'Sprint', weight 11 stone, last six positions, Personal PY for this race, class/handicap.


Posted By: sargesail
Date Posted: 29 Dec 17 at 10:06pm
Firstly I don’t accept the opening premise that handicap racing is the bedrock of dinghy racing.

It’s something that Sailracer have been pushing for a good while....but then it’s the basis of their business.

If there was a little more about how the slow boat had its day in strong winds too then that would be reassuring.

And I am absolutely sceptical about the 6% for an old solo, if it doesn’t include Crew Skill Factor.

And yes the logical destination would be crew weight based personal handicsaps. Let’s not go there.

Of course such an initiative might drive us all back go fleet racing!


Posted By: ian.r.mcdonald
Date Posted: 29 Dec 17 at 10:25pm
so you weigh in and get your py. what happens after the bacon sarnie before launching?

has the world really gone mad?


Posted By: 423zero
Date Posted: 29 Dec 17 at 10:50pm
The technology already exists for all types of factors to be programmed into a personal GPS device on whatever boat you happen to be sailing on any given day, (can't see my club taking it up), but for big events class or handicap it's just a decision away.


Posted By: Simon Lovesey
Date Posted: 30 Dec 17 at 7:55am
Originally posted by mozzy

The irony is the author only knows Dobson should be doing better because of results from class racing. 

We also have results from large handicap events to cross reference,  Ian Dobson has won the Grafham Grand Prix and Stevie Nichs, and been on the podium for the Tiger,  Datchet Flyer and Brass Monkey in the past, in addition to National and World championship wins in major classes.  
http://sailracer.org/ResultsEntry/Result/Sailor?sortOrder=Rank_asc&SailorName=Ian%20DOBSON 

Originally posted by mozzy

Making the handicaps 'dynamic' I think is missing two points. 
1) The numbers are still generated from performances which are the product of boat and crew. No amount of statistics up-speak will gloss over the fact that they are inseparable and without a clear methodology the talk of 'vast amounts of data' , 'standard deviation and confidence interval' is just massaging numbers until the names the author thinks should be winning, are winning. 
I agree that CSF can have an influence,  but that is the same with PY.  We are only focussing on very large handicap events (circa 100) boats,  with a high incidence of multiple boats from each class,  which reduces some of the CSF influence.  

Originally posted by mozzy

2) I don't like the result not being obvious on the water. Corrected time handicapping is bad enough in this regard, but at least the maths are simple enough that you can estimate in your head and understand the calculation to check it ashore. No point being more accurate if people can't understand and believe it.  

I agree that with a small fixed length club handicap race it is possible for sailors to estimate their corrected finish position,  and with similar boats racing each week build up a ready reckoner of minutes you need to beat a slower boat by or minutes behind a faster boat.  BUT for a large average lap race with 100 boats and 40 different classes over three starts,  where Toppers may only manage 1 lap and Moths 5 laps, I think many people would find it a challenge to estimate their corrected finish position.  


-------------
http://www.sailracer.org" rel="nofollow - www.sailracer.org
Online Sailing Results, GPS Tracking & Event Management


Posted By: Guests
Date Posted: 30 Dec 17 at 9:38am
I'm not convinced that a variable rating system such as this is desirable - not knowing your PY at the start seems strange and off putting, but maybe this is just my prejudice and resistance to change. Having said that, I do wonder if probabilistic PYs could help. In that method a boat does not have a single PY value but a range associated with some form of distribution. The outcome is that when calculating the results, this distribution is used and a boat may have say a 10% probability of first, 25% 2nd, 50% 3rd and 15% 4th. Then sum the weighted scores.


Posted By: PeterG
Date Posted: 30 Dec 17 at 10:12am
Firstly I don’t accept the opening premise that handicap racing is the bedrock of dinghy racing. 

Indeed, and these attempts to endlessly further tweak handicaps just underline that. If it's really that important to race on a reasonably clear and level playing field then class racingis there, available and works..

Of course there are plenty of people who would choose to sail something that is not locally available in fleet numbers (and others who clearly want to choose a boat they think will give them a handicap advantage!), and that's why we have the PY system. It's a compromise, it's never pretended to be anything else, but it allows people to make a compromise choice between class racing and handicap racing in the boat of your choice.

No handicap system is perfect, and not will it ever be. Of course, handicap systems could and should be reviewed to make them as close a compromise as possible to a level playing field, as they are, and the endless discussions here prove. But if you start using GPS and trying to adjust handicaps for local conditions and even for local conditions of different legs of a race you have to start asking yourself WTF is the point!


-------------
Peter
Ex Cont 707
Ex Laser 189635
DY 59


Posted By: Guests
Date Posted: 30 Dec 17 at 10:39am
Originally posted by Simon Lovesey

Originally posted by mozzy

The irony is the author only knows Dobson should be doing better because of results from class racing. 

We also have results from large handicap events to cross reference,  Ian Dobson has won the Grafham Grand Prix and Stevie Nichs, and been on the podium for the Tiger,  Datchet Flyer and Brass Monkey in the past, in addition to National and World championship wins in major classes.  
http://sailracer.org/ResultsEntry/Result/Sailor?sortOrder=Rank_asc&SailorName=Ian%20DOBSON 
The problem is, with the way handicaps are calculated, boats which struggle in certain conditions must be offset by having lenient handicaps in other conditions. So if you point to this result and say he's too low down the fleet, you are at the same time pointing to his previous wins and saying he shouldn't have done so well. 

A better way to highlight the problem would be show how in class racing Dobson has never finished outside the top xx% in class events, making this result a significant outlier and that it's unlikely to be a duff day as he still had a large margin over the nearest fireball. 

I'd prefer it if the article didn't focus on individuals however as it comes across as fudging results until the names you know are winning. It would be better to illustrate the point with class averages. 

Don't the GL handicaps deliberately exasperate this problem by choice anyway?
"We are therefore aiming to handicap to the potential of the boat. An extreme example is the foiling moth, we will handicap for foiling conditions only"
Originally posted by Simon Lovesey

 
Originally posted by mozzy

Making the handicaps 'dynamic' I think is missing two points. 
1) The numbers are still generated from performances which are the product of boat and crew... 
I agree that CSF can have an influence,  but that is the same with PY.  We are only focussing on very large handicap events (circa 100) boats,  with a high incidence of multiple boats from each class,  which reduces some of the CSF influence.  

Originally posted by mozzy

2) ....No point being more accurate if people can't understand and believe it. 
I agree that with a small fixed length club handicap race it is possible for sailors to estimate their corrected finish position,  and with similar boats racing each week build up a ready reckoner of minutes you need to beat a slower boat by or minutes behind a faster boat.  BUT for a large average lap race with 100 boats and 40 different classes over three starts,  where Toppers may only manage 1 lap and Moths 5 laps, I think many people would find it a challenge to estimate their corrected finish position.  
[/QUOTE]
Like I said, it's bad enough as it is. But at least you can check and understand how the result is derived.  Whether that's on the water or when the result go up, this new method seems to push the point of understanding further away from the finish line. 

I like pursuit races, although I don't think the result is fairer, the result is instant, and you get that racing feeling of chasing and being chased on the water. 

I don't doubt that the authors are trying to produce fairer handicaps but what i really don't like about this article and the 'method' page on the GL website is neither actually give a method. They describe the aims; but the devil is in the detail. 


Posted By: Simon Lovesey
Date Posted: 30 Dec 17 at 11:17am
Originally posted by mozzy

I don't doubt that the authors are trying to produce fairer handicaps but what i really don't like about this article and the 'method' page on the GL website is neither actually give a method. They describe the aims; but the devil is in the detail. 

Dynamic GPS Handicapping Method 
  1. Using the GPS data (length,  angle,  speed,  time, VMG etc) for each leg a Course Speed Profile (CSP) is calculated for each class.
  2. The database of previous races is then referenced to filter down to similar races 
  3. The dynamic handicap is then calculated from the suggested handicaps for those races (in a similar manner to PY)
We are very much at an experimental stage,  but the early outcomes are encouraging,  showing the faster boats getting a boost in the lighter conditions and the slower boats benefitting when the breeze starts to pick up. 


-------------
http://www.sailracer.org" rel="nofollow - www.sailracer.org
Online Sailing Results, GPS Tracking & Event Management


Posted By: Guests
Date Posted: 30 Dec 17 at 11:37am
But how is CPS calculated? Those variables define the type of leg it is, then I guess you use the time it takes a class to complete a leg compared to other boats to produce a PY.  

What is the output of CPS? Is it a PY number specific for a leg angle and wind force?

Then in the article you talk about 'modes'. Its not clear how this relates to CSP. Do you take the characteristics of the leg to determine what mode the boat should be in for that leg, and have a PY for each of that classes modes? Then their PY for the whole leg will be weighted by the length of each leg and which mode the model determines the class should be in for that leg? 

Where did the met data come from? 




Posted By: Simon Lovesey
Date Posted: 30 Dec 17 at 11:53am
Originally posted by mozzy

But how is CPS calculated? Those variables define the type of leg it is, then I guess you use the time it takes a class to complete a leg compared to other boats to produce a PY.  

That is the basics,  we know the length and angle of each leg,  with time taken for each boat.   

Originally posted by mozzy

What is the output of CPS? Is it a PY number specific for a leg angle and wind force?
It is more a performance and efficiency indicator -  so if 10 was the optimum and a class is performing at its peak,  and 1 where it is really struggling eg a foiling Moth in non-foiling mode,  with all the associated drag and a low LWL

Originally posted by mozzy

Then in the article you talk about 'modes'. Its not clear how this relates to CSP. Do you take the characteristics of the leg to determine what mode the boat should be in for that leg, and have a PY for each of that classes modes? Then their PY for the whole leg will be weighted by the length of each leg and which mode the model determines the class should be in for that leg? 

Yes along those lines

Originally posted by mozzy

Where did the met data come from? 

We can import a weather file,  with time stamps,  direction and speeds etc,  but that is not always available and we then use the CSPs to determine how well each class is performing. The system will try and calculate wind direction based on angles etc. Obviously the more data the better.  





-------------
http://www.sailracer.org" rel="nofollow - www.sailracer.org
Online Sailing Results, GPS Tracking & Event Management


Posted By: zippyRN
Date Posted: 30 Dec 17 at 12:05pm
Originally posted by 423zero

I think Merlin class and Finn class do this already, new handicap and classic handicap.
\

however the  Merlins and National 12s  do have  fairly easily defined epochs  due to  their  development  class nature , not sure how that works for the Finns 


Posted By: Guests
Date Posted: 30 Dec 17 at 2:16pm
Okay, so for each class you will have a series of modes, which will be factor of how achievable their handicap is in that given mode. 

Then for each class you will have some formula that defines which mode each class should be in for each leg. This is based on wind speed and direction, but in absence of that it is taken from back calculating to relative performance to other classes to estimate wind speed and direction. 

I'd be interested to see how wide the bin ranges are for true wind direction and wind speed. You already have 7 modes (although not all will be applicable to all classes). 

At most basic you could have three wind directions (upwind, downwind and reaching) and maybe five wind speeds (0-5, 5-10, 10-15, 15-20, 20+). That's already 15 types of 'leg' you have to define a assign a mode to for each class. 

Would you publish these tables of modes and handicaps for different types of leg in the NoR? There's enough chatter now when the handicaps come out... imagine the polemic with people sorting through tables of modes! 

Then the handicap over the entire races will be weighted by the amount of time each boat spent on each leg and what their corresponding mode should have been for hat leg. 

Handicap races are over time, so you will need to time each boat on each leg. So it's only ever going to be something that can be applied when everyone is logging GPS. If you're using leg times to calculate results you'll then have to define completion and timing of legs in the sailing instructions. 

It's all very complicated. But I admire the effort you're putting in.

Fundamentally I don't think handicap racing is, or should be the bedrock of dinghy racing. So maybe that is fuelling my criticism. It's great if we have some numbers that allows kids to race parents after school and calculate results while sailing ashore. 






Posted By: Simon Lovesey
Date Posted: 30 Dec 17 at 2:37pm
Originally posted by mozzy

Okay, so for each class you will have a series of modes, which will be factor of how achievable their handicap is in that given mode. 

Then for each class you will have some formula that defines which mode each class should be in for each leg. This is based on wind speed and direction, but in absence of that it is taken from back calculating to relative performance to other classes to estimate wind speed and direction. 

I'd be interested to see how wide the bin ranges are for true wind direction and wind speed. You already have 7 modes (although not all will be applicable to all classes). 

At most basic you could have three wind directions (upwind, downwind and reaching) and maybe five wind speeds (0-5, 5-10, 10-15, 15-20, 20+). That's already 15 types of 'leg' you have to define a assign a mode to for each class. 

Would you publish these tables of modes and handicaps for different types of leg in the NoR? There's enough chatter now when the handicaps come out... imagine the polemic with people sorting through tables of modes! 

Then the handicap over the entire races will be weighted by the amount of time each boat spent on each leg and what their corresponding mode should have been for hat leg. 

Handicap races are over time, so you will need to time each boat on each leg. So it's only ever going to be something that can be applied when everyone is logging GPS. If you're using leg times to calculate results you'll then have to define completion and timing of legs in the sailing instructions. 

It's all very complicated. But I admire the effort you're putting in.

Yes complicated,  but all done automatically -  trackers on the boats and buoys etc are uploading all their data  in real time,  with all the clever processing done in the cloud.  

Originally posted by mozzy


Fundamentally I don't think handicap racing is, or should be the bedrock of dinghy racing. So maybe that is fuelling my criticism. It's great if we have some numbers that allows kids to race parents after school and calculate results while sailing ashore. 

I actually agree,  growing up in an era of 200+ boat nationals, unfortunately that horse bolted some time ago,  and I think we are best looking forward,  seeing what can be done to improve a sailing scene that has significantly changed in recent years and under increasing competition from other leisure activities.  


-------------
http://www.sailracer.org" rel="nofollow - www.sailracer.org
Online Sailing Results, GPS Tracking & Event Management


Posted By: 423zero
Date Posted: 30 Dec 17 at 2:39pm
ZippyRN,
Article from Dougal about Finns.

http://www.yachtsandyachting.com/news/177256/Little-and-large-meet-again


Posted By: Sam.Spoons
Date Posted: 30 Dec 17 at 2:49pm
Does the system take crew weight into account?

-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: Simon Lovesey
Date Posted: 30 Dec 17 at 2:59pm
Originally posted by Sam.Spoons

Does the system take crew weight into account?

No -  like PY we assume that people select a class that broadly suits their size and physique,  and of course one they enjoy sailing Smile


-------------
http://www.sailracer.org" rel="nofollow - www.sailracer.org
Online Sailing Results, GPS Tracking & Event Management


Posted By: Sam.Spoons
Date Posted: 30 Dec 17 at 3:05pm
How much difference does weight from one end of a given classes weight range to the other make? I'd have thought it was considerable in some conditions.



-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: zippyRN
Date Posted: 30 Dec 17 at 4:31pm
Originally posted by 423zero

ZippyRN,
Article from Dougal about Finns.

http://www.yachtsandyachting.com/news/177256/Little-and-large-meet-again

thanks for that , so it;s basically  rig choice  that sets Classic Finn   away from Modern Finn .


Posted By: 423zero
Date Posted: 30 Dec 17 at 4:49pm
Age of hull and whatever owner decides to rig it with, another complication to add to problem of PYAG and Sailracer.


Posted By: Loyboy
Date Posted: 30 Dec 17 at 5:18pm
I finished 25th in Solo 186 at the Inland Championship in 2010 in a fleet of 97. Albeit with a modern rig and a hull seriously wet and dried. I also hit the right corners at Rutland.


Posted By: Sam.Spoons
Date Posted: 30 Dec 17 at 5:38pm
Good effort, where would you have expected to finish in a brand new Winder?

-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: Dougaldog
Date Posted: 30 Dec 17 at 5:38pm
Gosh ZippyRN- I'd forgotten about that!  Sadly, I've not seen that much going on regarding the classic Finn scene so haven't any visibility of what they're doing with PYs (though sadly I'm not hearing 'good' stories coming from there). There is much more going on in the lowrider classic Moths, but as more boats come on line, they're going to have to address the PY 'thing' - my guess is that this will come to a head it 2018.
As for the classic Merlins, I think that some of you are being overly generous to them with respect to their setting of classic PYs. Put bluntly, it's a messy dogs dinner! I worked with Miles James and the 'woodie revival' fleet (that AFAIK is still un-recognised by the class) and developed a far more intuitive list of PYs that have been used successfully elsewhere, but as this was something of a private venture, it has yet to get any wider distribution. My guess is that given the mindset within the class, it will end up just being used at the better but not class sanctioned events.

Handicapping classics is a topic all by itself and is very different - you may well be looking (as an example) to reward boats that retain more of the features that would have been present when they were first registered, whilst penalizing those who've put state of the art raking rigs onto a 1950s hull, or you might have a different objective in mind.

But all this has nothing to do with  the OP and the attempts by SR and others to try something different and it is at best disingenuous to somehow try to make one scenario apply to the other.
I can but refer you back to that 'other' article once more (yes, I know, 'I am not a number' gave a few of you a  bad bout of indigestion ) and the historical point that handicapping was originally time on distance, which was considered back then to be better than time on time. So what if SR could, with some clever programming and the power of modern systems, now make ToD work?
I for one (and I have no association with SR, the man from Kent, or anyone else for that matter) would applaud them for at least trying. It may not be the solution, it may not even be a step in the right direction,  but at least they are trying something different and for that we should sit back and wait to see what they can - and cannot do. Doing the 'other thing' means just sitting back and doing nothing  - which as my next article, due out very shortly will highlight, just isn't an option any longer!
Dougal/Ventnor/Isle of Wight


-------------
Dougal H


Posted By: Guests
Date Posted: 30 Dec 17 at 6:38pm
Originally posted by Dougaldog

Handicapping classics is a topic all by itself and is very different...But all this has nothing to do with  the OP and the attempts by SR and others to try something different and it is at best disingenuous to somehow try to make one scenario apply to the other.

I think the posters here have been unfairly lead astray by the SR article itself which does talk about older boats in it's introduction. 

I am the worst for long ramblings posts, but I do think the SR article conflates a few issues. The last four sections are touching on further topics and the language is very wishy-washy. 

It could be summed up as:
Classes perform differently in relation to one another for a given leg depending true wind angle and strength. Having a single PY number which covers all courses and conditions is therefore not appropriate.  By reviewing historic data SR were able to group similar legs to spot trends in how classes were performing. This analysis suggests that performance is dictated by the 'mode' a class sails. I.e. foiling, displacement, planing, apparent wind. 

This phenomenon is best illustrated by some top fireball sailors, who when the course and conditions don't allow them to access higher performance modes, struggle to compete to their handicap. 

To allow different classes to remain competitive across a range of conditions and courses it is possible to handicap per leg by classifying the mode each class has the potential to sail in for each given leg. Time can be corrected per leg and an overall corrected time produced which is dynamic for course and wind strength. 

This is made possible by real time met data  and GPS allowing application of the dynamic handicap. Applying the dynamic handicaps to recent sail-juice series we see the results subjectively fall better in line with our expectations for the sailors involved. 

The rest of the article does seem to be throwing science / stats words in to build confidence rather than explain how things are actually calculated. 

Personally I'm a little sceptical of the 'mode' talk. I'd like to see evidence of the modes. And even then, why not just have a table of handicaps for each class in a matrix of true wind angle and wind speed pulled out from historic GPS data? 


Posted By: 423zero
Date Posted: 30 Dec 17 at 7:57pm
Thanks Mozzy, 
Don't like drifting threads, thought I had read "new versus old" somewhere.


Posted By: ian.r.mcdonald
Date Posted: 30 Dec 17 at 8:55pm
Originally posted by Loyboy

I finished 25th in Solo 186 at the Inland Championship in 2010 in a fleet of 97. Albeit with a modern rig and a hull seriously wet and dried. I also hit the right corners at Rutland.


I think this is at the centre of all this,whatever adjustments and gobbledegook is added, crew skill is the major factor. And are these calculations to honour or negate this?


Posted By: Rupert
Date Posted: 30 Dec 17 at 9:05pm
I don't think this is the right direction, but in defence of SR I can't see that crew skill is being negated in this method.

-------------
Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686


Posted By: KazRob
Date Posted: 30 Dec 17 at 9:32pm
Every time the subject of handicaps come up here (which is pretty often) I'm reminded of the great book by Peter Johnson - 'Yacht Rating' which apart from being necessary reading to understand nothing is new in the world of sailing but also contains a quote from around 100 years ago to the effect of 'inventing rules for the handicapping of yachts must be a fine pastime for a gentleman'.
Nothing changes!

-------------
OK 2249
D-1 138


Posted By: Do Different
Date Posted: 31 Dec 17 at 7:33am
"I for one (and I have no association with SR, the man from Kent, or anyone else for that matter) would applaud them for at least trying. It may not be the solution, it may not even be a step in the right direction,  but at least they are trying something different and for that we should sit back and wait to see what they can - and cannot do. Doing the 'other thing' means just sitting back and doing nothing  - which as my next article, due out very shortly will highlight, just isn't an option any longer!
Dougal/Ventnor/Isle of Wight"

Why is doing nothing no longer an option? (actually the current PY method is being tweaked all the time)

I presume you assert a perceived malaise in dinghy racing is caused by a defective rating system, what evidence is there to support this?

I suggest that perhaps rather than seeking for others to "do something" we as sailors look to ourselves and "get a grip" and accept and embrace that rating racing will always be a grey area. 

Surely for the majority of dinghy sailors (myself included) crew skill factor CSF has a bigger influence over a series of races than a few or even several points on the rating scale. For those of high and level CSF I would expect a grown up appreciation of rating racing.  


Posted By: Rupert
Date Posted: 31 Dec 17 at 8:58am
I can't see how supporting the current yardstick system is "doing nothing" either. Just sounds like political soundbites. Given that it has been said on here by Simon L that the technique they are developing is for the big events, not really for club racing (where it is possible to judge positions) it would seem PY still has a long and bright future.

-------------
Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686


Posted By: Loyboy
Date Posted: 31 Dec 17 at 10:05am
Possibly 10-15th.



Posted By: 423zero
Date Posted: 31 Dec 17 at 10:15am
New sailors aren't going to be put off by PY system either, they will be to concerned with actually getting round the course.
Does anyone actually know of a single instance of someone leaving sailing due to PY.
What we need is another "Mirror" "Miracle" to bring sailing back into the public consciousness, not necessarily a boat.
I can see a place in sailing for both systems, sailrace system would work really well for "Barts Bash" type of events, would give a quicker result anyway.
My club wouldn't be able to use sailrace system, we race in a country park, our clubhouse and facilities are about 50 yards from lake, we tow a caravan up to jetty, vast majority of our members struggle with pen and paper system.


Posted By: Sam.Spoons
Date Posted: 31 Dec 17 at 10:56am
Originally posted by Loyboy

Possibly 10-15th.


So the old hull, though well optimised and with a modern rig cost you 10-15 places at the front end of a very competitive fleet. What would you say that represents in percentage terms and what are the issues with the hull (weight, shape, stiffness) that make that difference. I'm asking because I see myself in a Solo at some point in the future, budget will be tight (so no new rig) and it'll be purely for club racing.


-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: Sam.Spoons
Date Posted: 31 Dec 17 at 11:06am
Incidentally, having just made that last post it occurs to me that one reason I haven't already bought a Solo or Laser is the small fleets at club level compared to the handicap fleet. It's unlikely that I will travel much (if at all) to open meetings so the bigger numbers (and element of randomness) hold some attraction.

-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: iGRF
Date Posted: 31 Dec 17 at 11:34am
Late to the party on this one and you'll have to forgive me for maybe not reading everything that's written so I'll bullet point my comments.

I naturally have a suspicion of all things commercial so am immediately reticent, would this require proprietary software from a monopoly supplier, I assume so.

Would all craft require tracking nodes?

Would all craft, (even us dead classes)get in on the act or would as at present we have to have competed in the SJ series for any consideration?

I can see the benefit of live tracking in major events and I don't doubt the data that 'they' have amassed is relevant, but I can't see it being any help whatsoever in dealing with the puddle banditerati that plague some of our lives.

Nor does it address the human skill factor in the way I'd like to be judged and the answer to another question that has plagued me. Which is worse, an ageing boat or an ageing helm? Can a young helm in an old boat beat an old helm in a new boat, assuming they both 'know their stuff'.

The holy grail being a solution that makes the actual craft irrelevant to a competition, so we could all line up in boats that suit our body dimensions and capability and still have a half decent chance of line honours should we start on time, go the right way, bang every shift, use every tidal advantage and not drop a tack or gybe.

I don't think that system gets us any nearer, but it would be churlish not to applaude the effort, and I do tend to agree with dougal that to do nothing would be wrong. Something new wouldn't necessarily force the old system out, something new could be used in parallel. Something new might bring a sense of stability, personally I think the rapid changes of late have damaged things far more than the moribund ways of old.

Then again it could also be argued that this outfit are partially responsible for screwing things up anyway, so should their reward be to fix it?

-------------
https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals      https://www.corekite.co.uk" rel="nofollow - New Core Kite website


Posted By: PeterG
Date Posted: 31 Dec 17 at 12:12pm
It's unlikely that I will travel much (if at all) to open meetings so the bigger numbers (and element of randomness) hold some attraction.

I think the last is an interesting point - the very fact that handicaps are not, and can never be perfect, is in itself a positive, particularly at club level. With a mixed fleet the fact that some boats will do better in some conditions than others ensures that it's not that same boat, or small set of boats, that can be guaranteed to lead all the races. That surely is something that should be welcomed?


-------------
Peter
Ex Cont 707
Ex Laser 189635
DY 59


Posted By: Sam.Spoons
Date Posted: 31 Dec 17 at 12:42pm
That's my feeling but I do come from the generation who venerated sportsmanship over the 'win at all cost' attitude that seems to pervade 'sport' these days Unhappy

-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: Sam.Spoons
Date Posted: 31 Dec 17 at 12:47pm
Originally posted by iGRF


The holy grail being a solution that makes the actual craft irrelevant to a competition, so we could all line up in boats that suit our body dimensions and capability and still have a half decent chance of line honours should we start on time, go the right way, bang every shift, use every tidal advantage and not drop a tack or gybe.

 

Yup, nail/head etc.



-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"


Posted By: 423zero
Date Posted: 31 Dec 17 at 12:58pm
I have always attributed decline in sportsmanship to 'John Mcenroe' I can remember my mother being appalled at his behaviour and the fact he got away with it, and was well payed.


Posted By: ian.r.mcdonald
Date Posted: 31 Dec 17 at 3:33pm
Originally posted by Loyboy

Possibly 10-15th.


and of course in this mythical race,there would be new frp Solo as winner and also one placed in the 50s and probably the 90s too



Posted By: Sam.Spoons
Date Posted: 31 Dec 17 at 4:15pm
Undoubtedly, but not sailed by clones of the same helm Tongue

What I'm really asking is is it a one missed shift difference or a sailing an extra lap difference?




-------------
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish"



Print Page | Close Window

Bulletin Board Software by Web Wiz Forums® version 9.665y - http://www.webwizforums.com
Copyright ©2001-2010 Web Wiz - http://www.webwizguide.com