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Best Improved?

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Robert
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Best Improved?

Post by Robert »

The “Most Improved” award at the Nationals has recently been recalculated. The new calculation has moved away from a “raw” measure of places gained to one of “percentage” improvement. This utilises the proportion of progress towards the top of the board that one has made over the previous year. This change raises some interesting issues regarding what sort of improvement we are trying to measure.

In short, the “percentage” calculation allows more able sailors to show their improvement. E.g. someone who was second the previous year may gain 100% improvement by coming first in the following year and thereby be “best improved” by gaining just one place. Whilst it may be said that it is harder to gain year on year improvement if one is nearer to the top of the table, higher order competitors are closer to the prizes, anyway.

The “raw score” calculation gives those lower down the ratings a better chance of showing improvement. This is because the lower down the table you start, the more places are available to gain and the lower places are arguably easier to improve upon. Those near the top of the table in the previous year are generally excluded as they do not have as many places available to gain as those lower down. Those in lower ranks have the encouragement of an attainable prize for improvement.

Both of the measures are valid and perhaps there is a place for each of them. If, however, the objective is to encourage those in the lower orders to have on opportunity for a special prize then the raw score method is more appropriate than the percentage one.

There is a “half-way” position which could be applied to recent results to see if a more satisfactory measure can be achieved. Quite simply, the answer is to mix both methods as follows:

1. Discount from the previous year’s results anyone who did not start the requisite number of races (say five for a series of seven races).

2. Calculate, for these competitors only, a percentage ranking and also a raw score ranking.

3. You now have two sets of results which can be treated just like the results of two races, so add each competitor’s scores (rankings) together to create a new ranking based on this.

4. Voila!

This may have to be done manually unless someone is very talented at using Excel. The only alternative I can see would be to revert to “raw score” but include condition “1.” above. All depends on what sort of improvement we wish to emphasise; those in a specific band (raw score), or a wider group, including those in higher orders (percentage mixed with raw score).

I haven’t yet tested this development (raw + percentage) on actual figures but I would be interested to know what people think of the idea.
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Martin Searle
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Nationals Scoring

Post by Martin Searle »

Folks,

This is next on my list to sort out once I have the news system up and running, I have been very busy at work since the Nationals so haven't had much time to do anything on News.

I think that all the scoring can be done by a set of programs on this site, the sub-competitions ie most improved, heavyweights, pro-am etc can all be worked out automatically from the individual race scores. In the case of Most Improved this would need some extra thought to guarantee that the person is the same person as from last year, ie a 2 John Smith type scenario, which one did the event last year.

I'll program in whichever formula is decided upon for the most improved competition its still being banded about.

It'll also have to deal with ties and discard handling but this should all be possible. Also deal with the situation when not enough races are sailed to have a valid championship as in 2003.

Its not too bad and I think that the end result will be worth it since it will also provide the capability of people not at the event being able to see the current scores, so your clubmates will know how great (or otherwise) you are doing. Provided there is an internet connection of course, it'll be able to run standalone on a laptop if no connection is present.

It'll take a couple of months to get up and running once I start writting it. But should save oodles of time at the nationals I think and get those results out much faster.

Martin S.
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Robert
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Re: Best Improved?

Post by Robert »

In my previous post I wrote: ...E.g. someone who was second the previous year may gain 100% improvement by coming first in the following year...
I should have said "someone who was second the previous year may gain 50% improvement by coming first the following year" My apologies for this. In realising such, though, I came to realise that the new (percentage) calculation is so heavily biased toward those higher up the table that it would probably be best not even to "mix" it with the "raw score".

For example percentage improvement rewards a 10th place the previous year with 10% for every improved place the following year. Likewise starting in 5th place gives 20% for every improved place.

The odds seem stacked against middle or lower ranking players and it would be difficult to devise a system which evened this out, despite my earlier hopes. Perhaps it would be better after all to acknowledge that this particular prize should be designed to reward those in the middle or lower ranks for showing significant improvement. With this objective in mind, the old system is valid provided that sufficient races have been entered by the competitor in the championship of the previous year.

Having said this I must add how much I enjoyed this year's event. It was well run and we owe much of our enjoyment to those whose hard work and experience went to put it all together, particularly during the difficult circumstances that presented themselves over past months. I, for one, am very grateful :D .
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Post by Bob Carter »

Hi All
I have been receiving an amount of mail on the calculation most improved category at the Nationals - so I asked Robert to kick it off on the chat page as I would like to hear the members views.

Up until 2007 we just calculated it as follows:

After selecting only those competitors who have sailed in the 2 successive National Championships, take this years place from last years place and the sailor with the most places gained wins the most improved trophy (a fine big silver pot).

Well George Wood suggested that this was unfair as it is much harder to improve near the top than it is near the bottom and that we should do it on % improvement. It is also less inclined to variability due to numbers who attend our Nationals. If one year we get 65 attend and the following year we get 35 attend and the same guy is last - then he has improved 30 places by the old formula but he is still last place!
This new approach was supported by a number of the committee including me so we gave it a try in last weeks Nationals. The result was that Kevin Morris was a worthy winner (in my view). The following is an extract of the results:
2007 2006 IMPRO-
COMPETITOR PLACE PLACE VEMENT PLACE

Kevin Morris 15 55 72.73% 1
Steve Sawford 2 7 71.43% 2
Keith Ball 9 25 64.00% 3
Kevin Dutch 3 8 62.50% 4
Robin Newbold 10 24 58.33% 5
Gordon Goldstone 12 28 57.14% 6
William Tusting 6 13 53.85% 7
Robert England 26 50 48.00% 8
Norman Grum 21 39 46.15% 9

The full chart will soon be available along with all the other special category results in the events section of this web site.
Now I have subsequently received a further suggestion that we should also exclude anyone who did not sail all qualifying races in the previous year. For example a really good sailor who does not sail in all races the previous year (e.g. say he just sails 2 races from 7) gets an artificially low place to record a huge increase from the following year. This is also a very reasonable suggestion. If I practice by applying it to 2007 results I get:
1) Steve Sawford
2) Keith Ball
3) Kevin Dutch
4) Robin Newbold
5) Gordon Goldstone
6) William Tusting
7) Robert England

ie. the only guy who is excluded is Kevin Morris because his wife was ill last year and he had to stop sailing after the first day. As it happens Kevin Morris was a worthy winner as he really has improved tons - mostly as a result of Erling's teaching in the pro-am. Now I'm much less happy with the result as the top 6 places in the most improved category would all have been top 12 placed helms at the Nationals who already got a prize. The more I think about it the less I like a formula based on % improvement as it seems to reward the good guys. It may be just that this Nationals was unusual in that we did not have many of the top sailors from last year attend. No 2nd, 3rd, 4th, 5th,10th, 11th, 16th, etc attended.

I think the Most Improved should reward the middle of the fleet - not the top guys like Steve Sawford, who already receives pots a plenty.

When I get some more time I will play with other formulae & other options on a number of the previous years results. Meanwhile, I'm keen to open it up for others to make their views known.
Fire away.......................
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Robert
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Er...

Post by Robert »

Bob Carter wrote:...Well George Wood suggested that this was unfair as it is much harder to improve near the top than it is near the bottom and that we should do it on % improvement. It is also less inclined to variability due to numbers who attend our Nationals. If one year we get 65 attend and the following year we get 35 attend and the same guy is last - then he has improved 30 places by the old formula but he is still last place!...

(and later)

When I get some more time I will play with other formulae & other options on a number of the previous years results. Meanwhile, I'm keen to open it up for others to make their views known.
Fire away.......................
Well I seem to have got a bit excited about this topic and emptied my head onto the page a bit - sorry about that. I think there must be a lot more to be said from others less excitable.

There clearly is a problem with just raw scores that I hadn't realised given Bob's above example. I think that Martin Searle's suggestion is extremely helpful, especially if we have to use a more time-consuming method of working out placings. Maybe we should use "how far from last" as a comparison in some way.

Would some bright "Spark" who is at Uni or College like to take the problem on as a Mathematical Investigation? It must be solveable.
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Post by Robert »

:idea: Would it be useful to take improvement, year on year, to the percentage position in the fleet and combine it with a proportion (ie a reduced amount of) George Wood's ranking (somehow)?

eg: rank how people compared according to whether they had moved from (say) 35% down the list to, say, 21% down. Then make another ranking based on a modification of George's method which wouldn't be quite as heavily wieghted in favour of the top guns.

Then you could treat both ranks like the results of two races in a series by adding each person's rankings together to make a new score and this would be the basis of the final ranking. :?:

Just a thought...
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Most Improved

Post by Martin Searle »

Folks,

Part of the problem is that its slightly subjective since the person who goes from 44th to 25th may have made a MUCH bigger improvment in their sailing than the person who goes from 3rd to 1st, since the top flight tends to be at a similar level thus luck may have entered the equation in the latter case.

Certainly you need to take into account the number of entrants and thus eliminate that from the equation in some manner (I'm no maths genius!). I could ask one or two people I know with Maths or Statistics degrees, how it might be solved with a bias towards the mid and end fleets. Perhaps a weighting system?, thus an end fleeter gets a statistical advantage of some sort (Golf Handicap like?) to try and level the playing field.

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Robert
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Most Improved

Post by Robert »

Good point Martin.

I think the important thing is to be agreed on on what the objective of the category is (as Bob says, the idea is to encourage middle order sailors - do people generally agree, or should we be "fair", whatever that may mean, to the top guns too?)

Once this has been sorted out then it should be possible to identify a ranking to show what we want - especially if Martin might know someone who can work it out, and also if Excel can do it for us in a fairly transparent way.

Does anyone else have a view?

Robert.
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Post by Steve Willis »

It should be possible to do something along the lines of the RYA calculations for getting personal PY numbers by adjusting every 4 races based on time performance against the average time of competitiors in a race (total elapsed time of all competitors divided by number of competitors) then rank improvers based on their change in position compared to the average.

Something to occupy the grey matter over the winter methinks.

I tried to do a ladder for our cat helms based on position and the number of boats in a race. 5th out of 10 =0.5 but 5th out of 15 = 0.33 (i.e. position divided by number of entrants in race) and add all the scores together for the season leaving out the worst score for every ten races. Then divide the score by the number of races to get an average.

It worked reasonably in terms of ranking our helms but was only a trial.
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Post by Bob Carter »

Steve,
Corr - that sounds complicated. You have to remember that we have to calculate all the results after the last race and then do a prizegiving soon after. Each year it seems to take longer than expected - as I'm sure most participants will confirm. This year Gordon protested Erling in the last race and we had to do them again after Erling retired. Hopefully, Martin will bring some inspiration to speeding up the calculations now that he has agreed to look at it.
Whatever we do on the most improved, it must be formula based and the result needs to be calculated at the press of a button. I quite like Robert's idea to do it based on percentage place in the fleet (rather than absolute place) to reduce the variability due to the number of entrants in successive years. Any other ideas folks?
Cheers
Bob

PS You can now look at the full table (plus all the other results we calculate after the last race) as Martin has uploaded them on this site. Many Thanks Martin
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Most Improved

Post by Martin Searle »

Folks,

The latest thought I've had is to use the average point score (excl. DNS,DNF and DNC's). So say someone in one year has a point score in the 40's and then they improve the following year to recording mostly 20's then this should indicate an improvement, the person with the biggest change (upwards not downwards) in their average wins. Probably some account of number of entries needs to be made. Perhaps a little too similar to position improvement?

Anyway food for discussion.

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Post by Bob Carter »

Just to finish the tale, sometime back Robert England proposed the following change in an EMail to me (and the committee). This is an edited version:

Hi Bob

I’m afraid my terrier-like preoccupation with this issue has caused me to go a little further with my thinking, so I hope you might soon be feeling like having another look.

As you might suspect I have refined my thinking and have some suggestions in this direction. It will be important to simplify and make transparent the mechanism used so that people know what to expect. Validity and reliability are essential. Here are my thoughts:

· Sources of distortion, such as variation in numbers of entrants and the vagaries of raw placements need to be excluded.

· True progress (or otherwise) year on year needs to be demonstrated.

· Qualifying competitors should be measured against each other, not new or missing competitors who have/have not entered.


So,

· Only count the placement of competitors in relation to those who qualified for this category.

· Disregard any intervening placements of non-qualifying competitors in calculating the positions of the candidates for each of the two years to create “adjusted” places.

· Simply assess progress based on these “adjusted” placements.


The procedure is as follows:


1.List only competitors who qualify through starting sufficient races in the previous year and also being present at both competitions.

2.Place them in order of success for each year. This is the basis of the category and creates “adjusted” placements.

3.Compare progress from one year to the next.

4.Place the competitor who has gained the most places at the top (and so on).

5.In the event of a tie, then position in the current championship is the deciding factor.


It is the exclusion of the other results that is important in a) making the numbers the same for both years and b) making the results valid by comparing progress only in relation to qualifying competitors (for this category).

If this cannot be automated by Martin Searle, I would be willing to spend some time at the next championship manually feeding in information and helping as and when necessary.

Cheers

Robert


More shortly...................................................
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Post by Bob Carter »

So I worked out the different options ( 8 ) that we have to calculate the Most Improved winner and they are as follows:

1) Last years place – This years place

2) As (1) but exclude anyone who did not sail the number of qualifying races in the previous year.

3) As (2) but normalise the places in each year to places out of (say)100

4) As (2) but remove all those who did not complete a full series in both years in question. Renumber the positions for both years. Then do calculation (Last years revised place - this years revised place). This is Robert England's suggestion.

5) (Last years place/This Years Place)x100%

6) As (5) but exclude anyone who did not sail the number of qualifying races in the previous year.

7) As (6) but normalise the place in each year to (say) 100

8 ) As (6) but remove all those who did not complete a full series in both years in question. Renumber the positions for both years. Then do calculation (Last years place/This Years Place)x100%


I then did an Excel spreadsheet calculating the winners using each system for the the last 3 years Nationals results to share with the committee to judge the effect of the different methods. Some notes/observations were:

a) It is a no brainer that we should exclude competitors who get a false (poor) position the previous year. This removes options 1& 5 from further consideration.

b) We used Option 5 in 2007 for he first time. Prior to that we had used option 1.

c) Option 4 - the calculation is a pig to do in a hurry BUT it does have the big benefits of removing all possible source of variation. It just compares the relative places of the same group of sailors in 2 successive years. Thus, if the attendance is very different or if a group of star sailors are absent in one year the effects ARE TOTALLY REMOVED.


Conclusions

The results of applying Option 4 methodology are the fairest and the most beneficial to the Class by encouraging improvement in the ranks. The calculation, however, is complex and hard to do in a hurry. Martin Searle has implemented a web based system to automate the calculation of our results for the Nationals , including a system to calculate option 4 at the press of a button.

The committee have voted in favour of Option 4 - so this is what we will do next year.

Our thanks go to Robert England for proposing it AND to Martin Searle for making it possible by writing the programme.
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Most Improved

Post by Martin Searle »

Folks,

If you would like to see an example of the results my nationals scoring system is generating then I have setup an example for the 2008 Nationals using the results from 2006 as the data and using the results from the Saundersfoot nationals this year, then visit the following page:

http://www.sprint15.com/testing/nationa ... .php?id=28

Presently I'm testing it out after some bug fixing to the Tie Breaking system so I have entered just 3 race results but over the coming week the rest will be entered into the system.

To give you some idea as to the speed of the system it takes me about 10 minutes to enter the results for each race, with a double check and the system will then calculate the results in 1 second for ALL competitons and resolve all the tie breaks.

What this should allow is for us to publish results onto the web on a day by day basis allowing friends and family to keep track of your position in the event. Plus it'll save Bob oodles of time.

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Most Improved

Post by Kevin Parvin »

My first Nationals at Pwllheli was Ok 31st out of 33 !!! Well not so good really. But you could say that with a smaller fleet only the hot shots turned up that year..

At Netley I came 30th out of 65 (I think), have I improved by one or 34 places ? Bit of a glass half full or empty moment. Well at the time I was pleased with my performance.

At Saundersfoot I came 27th out of 50 or so. At this rate I shall have retired before I make the top ten.

Martin mentioned something in the inverse P discussion about 'big fleet block', ie just get round in one piece and do the best you can !! I get a bit of this I must admit.

I need to make a training weekend and concentrate on my starts...once out of the blocks I sail OK...
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