Thursday 1 March 2012

National Grading Scheme

The National Grading Scheme (NGS) has just gone live and there have been some significant updates to the members area. Also, there is now a new NGS Rankings page which you can visit to see the highest graded players and partnerships in the country, search for your friends and see some statistics about how the players are distributed amongst the various grades.



Here you can see the top players. The navigation links in the top left take you forward and backwards through the list and the 'Hide Evolving Grades' link will remove the players who haven't yet played 1000 boards (shown with a grey background with an 'E' icon on the right).

Search is simple - just type the surname of the person you're interested in in the box at the top right and hit enter. If you're searching for a common name it can get a bit slow, so you can add a comma after the surname and then the first few letters of the first name to narrow it down further. For example, try "Smith, P".



Members Area

In the members area you'll see three new columns in your sessions list. These are:

Sopp - the strength of your opponents in that session
Par - your percentage score compared with 'par' for that session
Grade - your resulting grade after that session


If you don't see these values for a given session it means it hasn't been processed by the NGS. This could be for a number of reasons, including: it's too recent (so wait a few more days), it's a teams event, it's a Sim Pairs result (only the local club heats are counted) or something went wrong.

As with many of the tables in the members area, you can click on the headings to sort them. So you can easily check just when it was that your grade was at its highest!

On the right you'll see a new button called 'NGS Info', under 'Change Password'. Click this to get up a new page which shows you information about your grade and your partnership history. You'll see all of your partnerships listed, but there will only be grades for the ones where you've played 300 boards or more.

Club Area

Club administrators will now also see some new features. The Members List will include a Grade column, with an icon indicating their Grade Band. Again, you can click on the header to sort it and find out who the best player in your club really is. The sessions list also includes a new column.



Here you can see the new NGS column, which will show the Strength Of Field for that session when it has been processed by the NGS (you can sort on this field too). The egg-timer icon indicates that the session is too recent to be processed. A red cross will indicate that it couldn't be processed for some reason. Hover your mouse over the icon and it will give you a description of why this happened.

Further Information

This was just a quick walk through the new features. For a more in-depth look at how the NGS works, take a look at the Full Guide, which includes comprehensive FAQs. Further queries can be addressed by email to ngsqueries@ebu.co.uk. Please note that we may not respond to your query directly but your email will be read and you'll be included in any bulk responses we send out in future.

107 comments:

  1. Patrick O'Callaghan4 March 2012 at 22:16

    The search function does not work for names beginneing with O followed by an apostrophe such as O'Neill. Can you explain how to do this on the website?

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    Replies
    1. Good point, Patrick. It will work if you use two apostrophes e.g. O''Neill, but that's obviously not ideal. Something we will have to fix.

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  2. The search function does not work for me, nothing happens when I type in the box & press enter.

    Josephine

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  3. Same as Josephine above. Using IE9.

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  4. The search does not work for me either - absolutely nothing happens!
    Also using IE9 on a Win 7 64bit laptop.

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    Replies
    1. Noted, thanks. Something we'll have to look at. In the meantime, you'll just have to use another browser if you want to access this information.

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  5. i think the national grading scheme is a poor thing. it will stop good players playing with new and improving players incase it brings down there grade !!

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    Replies
    1. You're wrong about that, Mr Anonymous. The NGS takes account of your partner's strength so you won't need to score so highly to keep your grade.

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    2. You also might be able to get by by switching to 'compatibility mode' in IE9.

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    3. Yes - 'compatibility mode' makes it work in IE9. Thanks Mike.

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  6. The search failed for me (nothing happens) using IE9 on a WIn7 64bit desktop, but worked with Firefox on the same system.

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  7. It would be nice to look at all the grades just in your county

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    Replies
    1. Yes - 'just my club' would be my first choice - and 'just my county' also interesting. Also please, for the 'main' list - a 'hop to page' or 'hop to position'. It takes ages to scroll thru the list (yep - I have too much time on my hands....).

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    2. I agree - listings by club and county would mean you could easily find people you may be interested in

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    3. The first thing I looked for was the County listing, certainly more useful than a club listing. I was very disappointed!

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  8. Should sessions be included in the NGS calculations if those sessions are "novice" or "teaching" sessions? By this I mean sessions where a teacher is on hand to give advice about bidding or play.

    Will you publish a table of SOpp values for individual clubs to assist the "diffusion" process you describe, which will otherwise take many years.

    The effect you describe of "isolated" clubs maintaining a SOpp of 50% whatever their objective standard is potentially a problem within individual clubs where there are sessions restricted to particular classes of member, eg novices, and little mixing with the rest of the club. If, for example, a single member plays both in the novice sessions and the expert sessions, he will become the partner to avoid in the expert sessions. His rating will top up in novice sessions and drop in the expert sessions. The outcome for him is neutral, but for those partnering him in the expert sessions, it is a sure recipe for systematic grade deflation.

    Nick McCarthy

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  9. The search works on Firefox but you have to put the surname and then a comma before the forename. Who would think of doing that!! When you find the name - it gives no position. Can your position be found without scrolling through hundreds of pages?

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  10. Who would think of doing that? Well, anybody who reads the prompt which clearly says 'name, forename'. :-) Works with 'name,initial' too. Agree with wanting to zoom to your position in the whole table, although knowing your percentage and rank half-answers the question.

    Great system ... will encourage mixed ability events because getting 49% could improve your ranking and will probably improve your bridge. Makes giving a non-expert prize straightforward now (and 49% could win that too).

    I am sure we will see a few improvements over the coming months.

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    Replies
    1. Who would think of doing that? I meant why would it be set up that way in the first place - where else do you have to put commas when searching for names?

      Search doesn't work with Internet Explorer which surely a lot people with basic computer skills use.

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  11. Will we be able to search for partnerships at some point? Being able to see how someone gets on in partnership with others versus their personal NGS might be helpful in determining whether one might get on with a prospective partner...

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  12. We deviated five times from our usual partnership over the last year making one an Ace and another an 8. Now when we play together the Ace always gets a better grade than the 8. How can the 8 every catch up again now we always play together?

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    1. Perhaps the EBU could answer this one? I sympathise with poor old '8'. He is on a hiding to nothing. If they do well the Ace will get the credit for "carrying" a weaker partner, and if they do badly the Ace will keep his grade because it is assumed that '8' was the cause of the bad result. This seems to be a big flaw in the system.
      Things will always be weighted in favour of the higher-ranked partner.

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    2. Short answer: play more boards.

      Longer answer: assuming you play regularly together once a week, approximately 10% of your last year's scores were earned separately. That you managed to generate ~11-12% difference in grade over that few boards is quite spectacular. However, if you read some of the articles on how grades are calculated, you'll see that it's time-weighted - ie recent boards count for more than old ones, and really old scores cease to matter entirely. Ergo, eventually the "rogue" scores will drop out of your grades, and you'll naturally converge (presumably at about J level).

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    3. An interesting case, and a possible flaw with the new NGS, although many partnerships where two people are of unequal strength must be in the same boat. I agree with the comment above that the difference in grades is indeed spectacular but not that the solution is to play more boards. Future results (good or bad) will presumably affect both partners equally so I am not sure the two different grades will ever converge unless the stronger player gets some poor results playing with other partners. I too sympathise with poor 8 but perhaps NGS is right and their grades are a fairly accurate reflection of their respective playing abilities?

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  13. What is the point of the NGS? Unless the EBU is proposing to hold competitions restricted to players of certain grades......in preference to the current system at some Green Point events where the 'B' Flight is restricted to players below a certain rank?

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    1. I think the biggest point of it right now is to be fun and interesting to the members. I'm not sure if the Tournament Committee have yet talked about how they might use it in EBU events, but it can also be used by clubs and counties, of course.

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    2. I disagree about the "fun" bit. It will encourage conservative and boring play. No more experimenting with new systems and conventions unless you are happy to risk your current grade going down! What a shame. The NGS will boost the egos of the top players no doubt, but will have a stultifying effect on everyone else.

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    3. Speculate to accumulate! I don't agree with this last post at all. Most people will enjoy the challenge of improving their grade, and if that requires a short term investment in temporarily depressed results while a new system or convention beds down, so be it. That's life. I think the NGS will improve the overall standard of play if people look critically at why their grade has declined (or risen). Feedback must help.

      To dispel any notion that this post is from a top player boosting his ego, I am in the low 40's.

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  14. Several comments:

    1) Sometime ago, during a period of unemployment and using just a spreadsheet, I did something very similar to this for my local clubs. Subject to a few quirky phenomena, the algorithm the EBU is using works fine.

    2) For those who care about their grade (and I imagine very few actually do), don't play when you're tired and particularly don't play during a period of your life when you're stressed - your grade will suffer. Alternatively, stop caring about your grade and just go out and have a game - you might be less stressed :)

    3) Regular partnerships tend to better - obviously. But (again if you care) beware the effect of a few games with other odd bods if you do normally play with just one partner. Inevitably one of you will do better than the other in those few sessions and the algorithm with "think" the player who did worse is the poorer partner - even though the reverse could be the case. It isn't true that this discrepancy then becomes permanent - but it does take a while for the system to "rebalance" itself.

    Anyway, thanks for completing this work. I, at least, find it interesting.

    Nick

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  15. I think the NGS is a good idea, especially for juniors, but I suspect it may be just a "nine-days wonder". Initially one can have fun checking up on fellow club members but everyone knows who the good players are anyway. My guess is that after a few weeks most people will be interested only in their own grade.

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  16. Well done everyone for getting this up and running. We usuay come in the bottom half, but against high standard players so don't earn many master points, so it's great to see objectively how good we are.

    Hope you can sort out the searching issues soon, so I can compare mayself with the rest of the club.

    Michael

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  17. I welcome NGS as a great idea because it is dynamic and reflects the current position. Master points only really reflect number of times over your entire life that you have played.

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    1. While this is true, it seems a remarkable omission to have no team games included. In the Merseyside area, where league matches are on Thursdays and regular, a lot of players treat the local league as their own club and would be distressed to be ignored for grading. It is already difficult for them to become EBU members.

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    2. mm since the Merseyside League is not in P2P and so awards no master points how do you suppose that they could be included in this even if the system is changed to allow it?

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  18. I play in a regular partnership. Our grades differ by 5% as a result of a few sessions two years ago - as initially the grades changed quickly. The system strongly maintains the difference between us and I would now have to play very well for about twenty sessions with another partner to reduce it!

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  19. I am fascinated by the SID column. Is this national or local? It seems too low to be an overall national identifier but there are many gaps - some large - so it's not just unique to me. At least it manages somehow to be the same for me as for my partner. (And, of course, it is not chronological.)

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    1. That's the ID of the session you played and is unique for your club. Hover your mouse over it to get the full SID, which will be unique in the whole country.

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  20. Thanks. That makes sense now. I have two series from two clubs.

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  21. I've just released a new version of the NGS page to fix a few of the smaller issues: apostrophes, two-word surnames and surnames with accents. Let me know if I've left anything out.

    The IE9 issue still remains. For now you can fix it by switching to compatibility mode but we'll try and sort it out as soon as possible.

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  22. There is a fairly obvious way to "game" the NGS system, which I describe below. It could only be prevented by careful identity checks on club members to eliminate one individual having two separate "accounts" in the NGS.

    Suppose two players, let us call them R and S, set out to each to achieve top grades while, in fact being only average players. Assume that they are both initially 50%. R sets up an alias RF (R false) and S similarly sets up SF. They play together at Club1 under the names RF and SF and deliberately set out to lose. Assume they manage to get their grades down to 20%.

    They both register with Club2 under the names R and SF, and at Club3 under the names RF and S. Since bridge clubs are not banks, and do not have elaborate identity checks, this need not be difficult.

    R and SF play together in Club2 and, if R starts at 50%, the partnership has a par of 35%. If they play at a level equal to the club's SOpp, they will consistently score 15% over par, and before long R will have a rating of 65% and SF 35%.

    Now RF and S play together at Club3. By the same process S will get to 65% and RF 35%.

    Now RF and SF repeat the process of depressing their grades in Club1 and play again with R and S as described above.

    With a few iterations, R and S can achieve grades near to 80% while being average players.

    While this scheme was restricted to a single club, Young Chelsea or Sheffield, this form of fraud was impossible. But extension nationwide introduces this possibility.

    What will the EBU do to counter this?

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    Replies
    1. I suppose that might work in theory but I can't imagine anyone being sad enough to do it. There's no monetary reward for having a high NGS grade but yet these people are apparently willing to spend lots of time and table money travelling around the country cheating at bridge and lying to people.

      Anyway, don't you think someone will notice if a Two player seems to play consistently at an Eight standard, raises his grade up to an Eight, goes away for a few weeks and then comes back as a Two again?

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    2. I agree. It might - just - be noticed if a Two rapidly raised himself to Eight, disappeared and then came back as a Two again. But that is not required. Either of the false identities needs only to raise himself from Two (20%) to a .... Two (35%). How many club directors are going to notice that? Unless they are even sadder than the fraudulent players themselves and spend their time looking up the exact grades on the NGS enquiry page.

      This would be, evidently, reprehensible behaviour, but not actually proscribed at present. That could be dealt with by asking EBU clubs to include in their rules that each member had one, and one only, EBU number for the purposes of the NGS.

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    3. I'm not a director, but "playing to lose" would appear to contravene Law 72A so I'd say this behaviour was already proscribed.

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    4. Just how sad would you have to be to do this and to what end??

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  23. Great work guys and girls. Really exciting system. Based on some of the previous articles I have read I am expecting this to be a big success.

    A few people have already said this, but viewing ratings by county and by club would be a nice feature on the main site.

    Perhaps in the future pairs could tick the different systems and conventions that they play to demonstrate in a VERY unscientific way what the best pairs are using.

    Simon

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    Replies
    1. Glad you like it Simon. County lists are on their way. Club lists maybe not, although it may be possible in future some time.

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  24. We played in a tournament on 3 March. Why have the results not appeared in NGS yet?

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  25. Probably because NGS processes results at least 9 days from receipt.

    I presume you did well.....

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  26. Thanks, Barry. It's already 11 days (if you count weekends). I hoped for an idea of when they could be expected. Does updating require much manual input?

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  27. I played in a two-session county event on the 19th February (qualifier and final). The qualifier has NGS info against it, but the final doesn't. It doesn't look like a combined number from both sessions. The TD tells me that for County events he can't see any information at all (unlike for clubs) and has no idea why this should be. How do we find out if there was a 'problem' which needs fixing with the data, or if we just need to wait, or if everything's OK?

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    Replies
    1. There's currently a display problem with multi-section events that we're looking into. The session will have been processed correctly behind the scenes but it may not always appear in your personal sessions list.

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    2. Multi-section or multi-session? There was only one section.

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    3. I've just been told that this particular event had a separate issue, with carry-forward scores being included in the final ranking list. The NGS rejected it because the average score was well above 50%. We're looking into what we can do about this and what advice we can give to scorers who are running such events.

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    4. I suppose we could have scored the final without a CF for P2P purposes, and then calculated the Overall Rankings with a spreadsheet (and generated a null session P2P file), but putting the CF into the Adjustments of the Final seemed a lot simpler (for me as TD). I didn't know the NGS would barf on it...

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    5. This sounds like the Bedfordshire county pairs SF and F. Surely players would like to know what percentage they scored in the final (ie without the CF)? I know I would. How difficult is it to score the final separately and then show the total including CF in another column?

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    6. It's not quite as bad as that - if you look at the Bedfordshire County web page you can see your results from the final without the CF. Admittedly you have to divide the matchpoitns by 312 to get a percentage, but the CF adjustement is still shown separately. The Surrey county pairs results were published in a slightly better format in that they told you the 312 number (which you have to work out from the Beds results). The problem is with the file sent to the EBU for NGS purposes, which just uses a general purpose 'adjustment' field for the CF. I understand they are working on a solution for this - the specification for NGS files includes the possibility of a special 'carry forward' field, but no-one is (yet!) using it.

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  28. One thing that would be quite cute would be to look at an average SOpp by club. My local club seems to average about 55 for the sessions I've played there, which implies it is above average in some sense. Or would knowing where the 'weak' clubs are lead to an influx of players desperate for masterpoints...

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    Replies
    1. At least one club has already started publishing SOF values on its website for each session, and I'm sure more will follow. I don't know that we'll publish this ourselves, but it's an interesting idea. Maybe we'll do a "top 10 strongest clubs" or something.

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  29. It seems an anomaly that I can look up anyone's grading under this scheme, but I can't see their Master Point rankings.

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  30. I have compared my current ngs ranking with that of my regular partner and also regular opponents, without exception all of them have a higher national ranking than club ranking , I am the only player whose NGS rank is lower than my running averages at the clubs that I play at. The largest anomaly is one player whose club individual percentage is .25% lower than mine ( Both equivalent to J) yet in the NGS rankings my opponent has been ranked as K whereas I've fallen to 10 ranking. I cannot understand this as we play on the same night against the same fields.

    I would much appreciate an explanation

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    Replies
    1. I think an explanation might be a bit hard without knowing the details of your club's ranking system, or indeed of who you are. If you want to write in with a more explicit query, please send it to ngsqueries@ebu.co.uk.

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  31. The NGS Info button from Members Login is not working this morning.

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    Replies
    1. It has been out for a few days but it's now fixed. Thanks

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  32. Could you clarify something for me please. The NGS description document says on page 2 that older sessions contribute nothing to your current grade when you have played over 1000 boards more recently. I thought from reading some of the above problens that in practice it is extremely difficult to recover from past bad results from say 2010. For example if I play 1000 disastrous boards with Fred, averaging 35%, and then ditch Fred and play 1000 boards with Tamzin who is much prettier and also a much better player than Fred, averaging 65%, will the 1000 boards with Fred then count for nothing and my current grade be 65%?

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    Replies
    1. Your grade will depend on the difference between Tamzin's grade and your grade before you played with Tamzin. Nothing you do when playing with Tamzin can change this difference.
      If you started at 35% and Tamzin was 65% initially and you keep playing at 65% together, then it keeps this 30% difference - so you go to 50% and Tamzin goes to 80%! (Your average stays at 65%)

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    2. What "Anonymous" said is basically right. If the NGS believes you're a worse player than your partner at the start of the partnership then it's not going to have any cause to change its opinion if you only play together. You'll have to play a few times with other players to get yourself a more accurate assessment.

      This example is fairly unlikely, though. If your true grade is 65% but your partnership with Fred was only 35% then that puts his true grade at 5%!

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    3. So does this mean the original statement to the effect that 'older sessions contribute nothing to your current grade' is not really true? It seems to me that anyone's current grade is automatically affected by every session they have ever played, not just the last 1000 boards.

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    4. The NGS uses only the session grades from your last 1000 boards. Those session grades are partly determined by your grade at the time, though, so boards played before then will exert some influence.

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  33. But it doesn't keep the difference the same!! See my question March 7th and the first reply on March 8th and a question dated 9th March (none of which have been answered by Michael). The higher ranking player always gets a better result and the lower ranking a worse result so the difference gets larger.

    So . . Michael is saying . . the lower ranking player has to play with other people to change this. This is what caused the problem in the first place. I played with a so called good player who made a complete mess of things and now I am penalised everytime I play with my original partner.

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    Replies
    1. No, you're mistaken. Please see Q5 on our FAQ page:
      http://www.ebu.co.uk/ngs/faq.htm#question5

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  34. 1) Can l ask why most of the NGS information that is available can only be accessed by Firefox and not by using
    Internet Explorer which is the most used system. So why has the EBU decided to use this search engine. I only access the computer at local Libraries and Firefox is not allowed for computers in the public realm.

    2) Some questions asked by members seem to have been on the list of members observations for weeks,so why
    is nobody from HQ answering these questions.If the EBU wants to consult its members,and that is a very good idea,then at least those members who take the time and trouble to write in deserve an answer.

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    Replies
    1. No idea what you mean regarding Firefox. All the documentation files are in PDF format which should work on any browser.

      Most questions are answered in the documentation and FAQ. If you have any further queries then you can contact ngsqueries@ebu.co.uk.

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  35. (1) For regular partnerships, the NGS gives a very good Partnership grading - which is a smoothed estimate of actual performance (balanced by an adjustment for Strength of Opposition).
    (2) For generally regular partnerships, Individual gradings will only change when one partner plays with someone else. For established partnerships, changes will be small.
    (3) The problem lies with the way the NGS has initialized everyone's grades. If you played with someone else early one once or twice and now have a regular partner, your partnership grade difference is now *much* harder to change that it was initially.

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  36. Since club's sopps are known why not put on your site a list of clubs either with their sopp average over a number of sessions or at worst their last session?This would enable players going to a new club to check out the expected level of play.
    Out of interest what are the highest & lowest sopp figures recorded to date?

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  37. This system has to be deeply flawed.

    I have a grade of AC which seems to mean that I am one of the top 817 players in the country. I have been able to critically observe my play at close quarters for four decades and this rating hugely overstates my competence. Does anyone else out there have the same problem?

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    1. I think the basic problem arises if you are playing with a weaker partner, when it seems that for some reason the better player somehow gains an unrealistically high grade and vice versa for their partner. By a happy coincidence, the very week the NGS went live my grade hit the dizzy heights of 67% making me an Ace of Spades! I have to report that all of my bridge friends fell about laughing except my regular partner who was equally wrongly graded as an eight. I believe that a few poor results my partner had with other players early on in 2010 has caused the anomoly. Recently however my grade has dropped to AD and is certain to fall further when my latest batch of results go in, so maybe my grade will reach its 'correct level' before long. Unfortunately I don't think my partner's grade will ever recover to what it should be, which is making them extremely unhappy.

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  38. I agree with the last two posts, the system is indeed deeply flawed. The partner mentioned above is not the only person who is extremely unhappy. I have heard of a large number of other people. What is the point of it all? Why does the EBU want to start up something that is so contentious and of no use to anyone? A previous answer by the EBU said it was just "a bit of fun". Perhaps they could now listen to the voices of the people who don't think it is fun at all?

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    Replies
    1. Well, first of all you're misquoting me; "fun" and "just a bit of fun" are very different sympathies. We do think it's fun and we've had a lot of very positive feedback that agrees, but it's also supposed to be a good indicator of a player's strength and for the most part it is.

      Sure, there will be anomalies and you're certainly not supposed to stay at precisely your skill level without deviation. Bridge is inherently a pretty random game and people will go through good periods and bad periods. The anonymous poster above may well be over-rated at AC, but a few of these are not surprising out of 40,000 graded members and if he really is over-rated then he's very likely to go down over his next few plays. There will be others - as good a player as Hugh McGann is, I don't think anybody could ever have a genuine 77% grade!

      Whether a few of these cases are enough to make the system "deeply flawed" and cause people to be "extremely unhappy", I'll let you make up your own mind.

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  39. The amount of people who are posting as "Anonymous" has made things rather confusing when referencing their comments. From now on please leave a name if you want your comment to be published.

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  40. Hi Mike,

    My rating went up recently by more than I expected, so I counted back 40 sessions. I found the 41st was a particularly bad evening. Would it be correct to say that the 'dropping out' of that bad result (as it's the last 1000 boards that count) affected the new rating, as well as the most recent result?
    Or have the 'old' results degraded so much that dropping out actually has a negligable impact?
    Is there any way of showing us which sessions have dropped out of the last 1000?
    Thanks, Gill.

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    Replies
    1. Yes, if a particularly bad result drops out of the top 1000 then you will see a slightly bigger bump than you'd expect. This is why partners don't always rise and fall by the exact same amount. As to whether we can show which sessions have dropped off, I'm not sure. But it's a good idea and we'll see what we can do.

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  41. Thanks Mike, it would be useful - cos sessions are not all 25 boards, and anyway it's boring to add up the number of sessions lol. Gill.

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  42. Why don't all my partnership grades change when my personal grade changes?

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    1. The partnership grade with the person you were playing with will change, but other partnerships don't change. Why would they?

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    2. As I understand it, partnership grades are the average of the two individual grades so if one or both individual grades change shouldn't the combined partnership grade also change?

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    3. No, partnership grades are the grade the partnership has when it plays together. So two people could be 50s individually but combine well to make a 52 partnership.

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    4. Hello Mike,
      Great work. It's most interesting to watch my grade move up and down (ok, how sad is that!) and it definitely encourages me to try to play better bridge. However, my grade has been surprisingly unaffected by a string of bad results. Unfortunately my partners have let me down and recently I had six consecutive poor results with a total loss of 30 points to par but my grade fell by only 2%. Can you explain this please?

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    5. Thanks Michael. I shall see what happens when I play with one of my infrequent partners again. By the way, my query and your response have been timed as six in the morning so your clock needs correcting!

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    6. @G Smith - it might be that you had some very bad sessions 1000 boards ago which dropped out of your grading calculation? A 2% drop is still quite a bit, though.

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  43. On 12th March, my partnership grade with my Friday partner was based on 843 boards.
    On 16th March, our club duplicate was played over 27 boards.
    On 23rd March, our club duplicate was played over a further 27 boards.
    My Friday partnership grade has been updated and is now based on 891 boards but it ought to be based on 897 boards.

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    1. If the NGS can't figure out how many boards were played in a session it assumes 24, so that would seem to make the sums add up.

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    2. If NGS is grading all twenty-seven boards then NGS should be able to work out there were 27 boards in the session. Or does the NGS stop once it has reached 24 boards?

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  44. According to my NGS information I have played with 13 different partners but partnership grades are shown for only two of them owing to the 300 board minimum. As 300 boards is quite a lot (about 13 sessions) it is highly unlikely that I shall ever see a partnership grade for the other 11 occasional partners. Could you therefore consider showing the partnership grade for all partners irrespective of how many boards played?

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  45. With regards to your reply to Gill Harris (28th March). If I understand the degrading proccess correctly, each board degrades by 1/1000th of it's original value, for each subsequant hand played. So if I play 25 boards today, the last (1000th) board on my list only degrade once the next twice and so on, before drops off completely. Thus having less of an effect on my rating, than when the whole session had room to degrade ie each hand degrading 25 times.

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    1. Grading is done by session rather than board. A complete session drops off if this still leaves over 1000 boards.

      Alan
      [I can't see a way of not posting as Anonymous']

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  46. So at any one time, the grade is actually based on between 1000 and 1040(ish) boards, depending on when the earliest session falls.

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    1. Not really. See Michael Clark's reply above where he said although "the NGS uses only the session grades from your last 1000 boards, those session grades are partly determined by your grade at the time, so boards played before then will exert some influence". This is because your current grade doesn't start from scratch and in practice I believe that your current grade is affected to some extent by every session you have ever played.

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  47. My question concerns the connection or otherwise between individual grades and partnership grades (your reply to John Dakin above). My partner and I both had individual grades of 50% and a partnership grade of 50% the last time we played together. Since then we have both improved to 60%, so what is our expected par score if we were to play together again? Is it 50%, or is it 60%?

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  48. It's 60% when working out your individual grades but 50% when working out your partnership grade!

    Alan

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  49. My grades over the past months seem to go up and down in a way which is not directly related to performance. As far as I can see, this is because the grade shown is NOT the grade at the time of the session indicated. It is always calculated forwards to the present based on information derived at the time.
    For example if a session in mid-February emerges in May all my gradings from February to May will change but the EBU list will not show these changes. They just put my revised (May) grade down against the date in February.
    I accept that there is nothing unfair about this. It would probably be just as confusing to change all later grades. And, of course all would be perfect if my club submitted all of its results within 9 days. (So far my club seems to submit some in 24 hours and some three or four weeks later. )
    One final thought. It might be clearer if the EBU were to show session grades as well as the smoothed final grades.
    Alan

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  50. Hello Michael,
    Could you explain please how swiss pairs VPs are converted to MPs. In the recent Devon Congress we came 19th out of 114 pairs scoring 120 VPs out of 200 which I make 60%, yet our MP score for NGS somehow became only 52.84%. This percentage seems very low for a pair finishing in the top sixth of the field.

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    1. It uses your match point percentage, before it's converted into VPs. I don't think 53% is that low. If this was a 70-board pairs event (which is essentially how the NGS treats it), you might expect a winning score around 60% and 53% might well be a top-sixth score. Look at the results from the Easter Championship Pairs for an example.

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    2. It is true that the more boards played the more likely 53% will be a good score, as scores will tend to gravitate towards the average of 50%. The problem is that 53% is very low compared with club events of 24 boards where 3rd place out of 18 typically scores 58%. It doesn't seem right that a 70 board S/P event is given the same weight as a 24 board club event. Do you think that because of this, some adjustment is needed when a multi-session event is scored over a greater number of boards than 24? As an aside I notice the Portland Pairs has been scored as two separate sessions.

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    3. It already does this - the session will be treated as 70 boards.

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  51. Something must be wrong with this system? Since the rankings have been posted I have remained a J apart from 2 days in heady glory as a Q. Overnight, as a result of playing in a congress with another J, we have both plummeted to 8's as a result of four pairs sessions. (Our teams events did not count and were far better.) How can 4 sessions affect an average on 1000 boards by 6%?

    Kate

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    1. Kate, please email ngsqueries@ebu.co.uk and include your EBU number. Any answer I give here would be a pure blind guess.

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