EBU National Grading Scheme

[billw55]

A friend of mine has just asked me for a game. In round numbers, I am rated 63 and he is 70. The average field at the Young Chealsea is about 55. Does that mean we have to score 61.5% (or +43 IMPs) just to break even? Help!

This is the sort of thing I was talking about. Some players will look at such a situation and choose not to play, to protect their rating. Not you, of course, and probably not anyone who posts here. But some.

 

I wonder if a rating of 70 is sustainable at all, by anyone.

[gordontd]

I wonder if a rating of 70 is sustainable at all, by anyone.

All but one of those who have a rating of 70+ on the EBU's NGS are "evolving" - ie they haven't played the 1000 boards to provide a stable rating, so I imagine your are right.

 

I did know someone on OKbridge who had a Lehman rating of 70 & rising. I used to play with him when my rating was low, but as it improved he stopped asking me, and seemed to play less and less although he was usually online. He did however eventually achieve the maximum rating of 75. I think most people would rather play bridge though.

[phil_20686]

All but one of those who have a rating of 70+ on the EBU's NGS are "evolving" - ie they haven't played the 1000 boards to provide a stable rating, so I imagine your are right.

 

I did know someone on OKbridge who had a Lehman rating of 70 & rising. I used to play with him when my rating was low, but as it improved he stopped asking me, and seemed to play less and less although he was usually online. He did however eventually achieve the maximum rating of 75. I think most people would rather play bridge though.

 

On Ok bridge didnt people do this to counteract grade inflation? I never played but I heard that some players considered it a public duty to build up their ranking then create a new login.

[Vampyr]

we CAN say the average variability of a bunch of MP boards is equal to the average variability of a bunch of IMP boards.

Stephanie, I think this means we treat IMP pairs events fairly. It certainly isn't meant to be in the group of small effects that we ignore.

 

Is the average variability of a set of boards more accurate than the variability of the set of boards in question?

[Vampyr]

Some players will look at such a situation and choose not to play, to protect their rating.

 

I worry particularly about people showing up without a partner. In many clubs there are normally a fair few such people.

 

When I wrote a couple of years ago, I suggested letting any number of pairs opt out of their game being rated, rather than just the actual host. This suggestion was ignored, which I think is a shame.

[Blue Uriah]

I worry particularly about people showing up without a partner. In many clubs there are normally a fair few such people.

 

When I wrote a couple of years ago, I suggested letting any number of pairs opt out of their game being rated, rather than just the actual host. This suggestion was ignored, which I think is a shame.

You're assuming, a little cynically, that there are a lot of people out there who care more about their grading than about playing bridge. I guess we'll find out, but I hope that over time people will come to understand how the NGS works and realise that it doesn't really matter if you play with a weak partner or a strong partner - the system will take it into account. Of course, your new partner might be significantly over-rated and that will cause your grade harm, but they might equally be under-rated and you'll get a nice boost.

 

I think part of the fear is that people are very bad at comprehending randomness. If all parties are correctly graded then your grade should go up half the time and down the other half. But when someone goes down they'll probably blame their new scratch partner rather than bad luck or their own poor play and cry to the world that they've been damaged by their benevolent charity. They'll keep quiet when they get 65% and go up a grade band, though.

[billw55]

I worry particularly about people showing up without a partner. In many clubs there are normally a fair few such people.

 

When I wrote a couple of years ago, I suggested letting any number of pairs opt out of their game being rated, rather than just the actual host. This suggestion was ignored, which I think is a shame.

Definitely agree. Often at bridge, people just want to show up and have a relaxing evening having fun and socializing over some cards, and not worry too much about working out that endplay or trump coup position, or turning the knife for that extra undertrick against the club rabbits, etc.

 

The simple fact is, many people do care about their ratings. Because of this, if they don't feel like playing at their maximium effort on a particular day, they may choose to not play at all if they cannot opt out of rating for that session.

[gnasher]

Definitely agree. Often at bridge, people just want to show up and have a relaxing evening having fun and socializing over some cards, and not worry too much about working out that endplay or trump coup position, or turning the knife for that extra undertrick against the club rabbits, etc.

 

The simple fact is, many people do care about their ratings. Because of this, if they don't feel like playing at their maximium effort on a particular day, they may choose to not play at all if they cannot opt out of rating for that session.

So the effect of the rating system will be to discourage people who care about their rating but not about how well they actually play? That sounds good to me.

[TMorris]

I doubt that many will be more interested in how playing impacts their rating than actually wanting to play a game of bridge. There are a couple of large clubs not affiliated to the EBU and hence not getting masterpoints who are doing very well in my area & no doubt plenty others throughout the country. This shows that there is a demand for people to play bridge, have an evening out and enjoy themselves. Masterpoints & this grading scheme might influence a small number of people but only at the margins I would think.

[billw55]

So the effect of the rating system will be to discourage people who care about their rating but not about how well they actually play? That sounds good to me.

Exactly. It sounds good to you, and perhaps to many others posting on BBF.

 

But, I think it is safe to say that the BBF poster population is not representative of the total club playing population. BBF posters will tend to be serious enthusiasts who will almost always prefer competitive play over casual social play. Whereas in the typical club population, there will be many players, perhaps even a majority, who prefer the latter. So I believe that the typical club player will not share your opinion above.

 

Having enough attendance to keep club games going strong is important to the long term health of live bridge. Dwindling attendance is an ongoing problem (at least in USA). So, it can be argued that a rating system that may occasionally discourage attendance for some players is a bad idea - even if it does not discourage attendance for you or me or most of our peers.

 

(I hasten to add that I mean "peers" in the sense of competitive attitude and enthusiasm, but certainly not in skill, where you and I are concerned).

[Vampyr]

So the effect of the rating system will be to discourage people who care about their rating but not about how well they actually play? That sounds good to me.

 

I strongly disagree -- one of the most important aspects of any competition is the number of "arses on chairs".

[TMorris]

I strongly disagree -- one of the most important aspects of any competition is the number of "arses on chairs".

 

I'm rather more interested in quality than quantity. It makes for a more challenging game IMO.

[awm]

Last year when my local club had someone show up without a partner on a Saturday, I would often volunteer to play. This was mostly as a favor to the director and the club. Many of my partners were not strong players, and we rarely did well, but they usually enjoyed partnering a decent player who could hold his temper at the table. Further, when playing in these games I would try to just play a "solid game of bridge" rather than using tactics to turn the hands (and other such stuff that a strong player can do to carry a weak partner in). After all, the main goal was that partner have a good time.

 

If doing this would adversely effect my rating, I would probably not have volunteered. This is especially true if ratings are used for something (for example, if a low rating made it hard for me to be eligible for top flight events).

 

This is a serious concern -- being able to find a short-term partnership does contribute to getting many people out to a game.

[TMorris]

Last year when my local club had someone show up without a partner on a Saturday, I would often volunteer to play. This was mostly as a favor to the director and the club. Many of my partners were not strong players, and we rarely did well, but they usually enjoyed partnering a decent player who could hold his temper at the table. Further, when playing in these games I would try to just play a "solid game of bridge" rather than using tactics to turn the hands (and other such stuff that a strong player can do to carry a weak partner in). After all, the main goal was that partner have a good time.

 

If doing this would adversely effect my rating, I would probably not have volunteered. This is especially true if ratings are used for something (for example, if a low rating made it hard for me to be eligible for top flight events).

 

This is a serious concern -- being able to find a short-term partnership does contribute to getting many people out to a game.

 

There is an allowance in the system for a volunteer not to have that session included in the rating calculations. You have to tell the organiser in advance and they have to agree to it but the issue you mention should not be a problem.

[helene_t]

reading adam's above post, the endless discussions about bbo ratings come to mind.

 

Many of us who resist objective rating on bbo do so because of negative experience with rating at other sites: one of the issues is that rating makes people be particular about who they play with and against on the basis of the (perceived) influence it might have in their rating.

 

The situation in EBU is somewhat different. For example, the concern about cheating allegations won't be much of an issue because anyone who would be tempted to cheat to boost their rating would be cheating already (to boost their master points and reputation).

 

Even so, it could still be an issue.

[billw55]

There is an allowance in the system for a volunteer not to have that session included in the rating calculations. You have to tell the organiser in advance and they have to agree to it but the issue you mention should not be a problem.

If this option is available for volunteers, it should be easy to make it available for everybody.

 

Perhaps sympathetic directors can arrange this by entering large numbers of "volunteers".

[TMorris]

If this option is available for volunteers, it should be easy to make it available for everybody.

 

Perhaps sympathetic directors can arrange this by entering large numbers of "volunteers".

 

You might not be that surprised to hear that they actually thought this thing through and the option is available for ONE pair per session.

[Blue Uriah]

Last year when my local club had someone show up without a partner on a Saturday, I would often volunteer to play. This was mostly as a favor to the director and the club. Many of my partners were not strong players, and we rarely did well, but they usually enjoyed partnering a decent player who could hold his temper at the table. Further, when playing in these games I would try to just play a "solid game of bridge" rather than using tactics to turn the hands (and other such stuff that a strong player can do to carry a weak partner in). After all, the main goal was that partner have a good time.

 

If doing this would adversely effect my rating, I would probably not have volunteered. This is especially true if ratings are used for something (for example, if a low rating made it hard for me to be eligible for top flight events).

 

This is a serious concern -- being able to find a short-term partnership does contribute to getting many people out to a game.

Out of curiosity, how would you rate yourself? How would you rate your typical scratch partners? And how did you do on average when you were performing this host role? If you're a 60, partner is a 40 and you're playing in an average club then you only need to break 50% to improve your grade. Do you think you did worse than this more than half the time?

 

Also, don't forget that the more your grade goes down, the easier it will be (assuming your ability remained constant) to go up in future. In the long run you'll oscillate around your true average and shouldn't stop playing just because you're concerned about a perfectly normal downswing - it's just as likely to happen when you play with an expert.

 

Personally, I'd be more inclined to play with a beginner now than I would have been a year ago. Back then there was (realistically) nothing to play for except a righteous sense of civic duty, but now there's a tangible goal to aim for. If my partner is so bad that he averages 38% then I can still improve both our grades (and call the evening "a win") by scoring 48%.

[Vampyr]

You might not be that surprised to hear that they actually thought this thing through and the option is available for ONE pair per session.

 

Whether they have thought this through or not may be open to question, but it is certainly true that the option is available to one pair.

 

This does not help matters. If you are planning to show up without a partner you will be able to opt out only if you are the ONLY player showing up without a partner.

 

The EBU cannot have it both ways. If they really want the ratings that they have spent money and effort on to be something that people care about, they must allow people in random partnerships to opt out. Perhaps the solution is to ask the director to make a small alteration to your name. Then you will be eligible for prize money and ladder points if applicable, but not masterpoints or rating changes.

 

Better players will not care about ratings, just as they don't care about masterpoints. But I disagree that attendance at duplicates and congresses by only the better players is a good thing. Or a possible thing, because with such restricted numbers venues will no longer be affordable.

[billw55]

Out of curiosity, how would you rate yourself? How would you rate your typical scratch partners? And how did you do on average when you were performing this host role? If you're a 60, partner is a 40 and you're playing in an average club then you only need to break 50% to improve your grade. Do you think you did worse than this more than half the time?

An aside about the math: I wonder if this method is really an accurate measure of expected result. Bridge may have a sort of weak link effect, so that the 60/40 pair will not do as well, on average, as the 50/50 pair. As a more extreme example, I think I would bet two ordinary B players against Bob Hamman and a rank novice. Probably as enough results come in they can evaluate this effect, if they track the data appropriately.

[Cthulhu D]

Last year when my local club had someone show up without a partner on a Saturday, I would often volunteer to play. This was mostly as a favor to the director and the club. Many of my partners were not strong players, and we rarely did well, but they usually enjoyed partnering a decent player who could hold his temper at the table. Further, when playing in these games I would try to just play a "solid game of bridge" rather than using tactics to turn the hands (and other such stuff that a strong player can do to carry a weak partner in). After all, the main goal was that partner have a good time.

 

If doing this would adversely effect my rating, I would probably not have volunteered. This is especially true if ratings are used for something (for example, if a low rating made it hard for me to be eligible for top flight events).

 

This is a serious concern -- being able to find a short-term partnership does contribute to getting many people out to a game.

 

I wonder if playing with much weaker players wouldn't prop your ranking up. If hog a bit you should have a disproportionate effect on the partnerships performance, and if his expectation is a 45% session and yours is a 55% session, and you play a 52% game, you actually get a ratings bump. I disagree that there is a weakest link effect - there is a bit, but if you always try to maximise your chance of playing the hand better declarer play should carry the day.

 

The most difficult case is the same as Chess ELO ratings - a very strong pair might not want to 'risk' their ratings in a weak field, because their expectation will be very high and almost impossible to get because some boards are just flat. But playing with a client your strong rating is diluted by their weak one and you are not exposed to nearly as much risk, and if they are worse than you are good, it's actually great for you.

[Blue Uriah]

An aside about the math: I wonder if this method is really an accurate measure of expected result. Bridge may have a sort of weak link effect, so that the 60/40 pair will not do as well, on average, as the 50/50 pair. As a more extreme example, I think I would bet two ordinary B players against Bob Hamman and a rank novice. Probably as enough results come in they can evaluate this effect, if they track the data appropriately.

I'm sure you're right - it would be unlikely that the true skill of a partnership could be calculated so simply and elegantly as this. But it's interesting that you're guessing it's biased this way since someone else recently suggested that a 60/40 would do better than a 50/50. So there's probably not much in it.

 

Edit: in fact, while I was typing Cthulhu D said just that.

[Vampyr]

If hog a bit you should have a disproportionate effect on the partnerships performance, and if his expectation is a 45% session and yours is a 55% session, and you play a 52% game, you actually get a ratings bump.

 

You might have a conflict between improving your rating and being nice to (or just not insulting) your partner. Especially if it is not just a pickup partnership but a developing one.

 

I'm sure you're right - it would be unlikely that the true skill of a partnership could be calculated so simply and elegantly as this. But it's interesting that you're guessing it's biased this way since someone else recently suggested that a 60/40 would do better than a 50/50. So there's probably not much in it.

 

More significant is the difference between a 50/50 regular partnership and a 50/50 pair arranged for this one session.

[gordontd]

Last year when my local club had someone show up without a partner on a Saturday, I would often volunteer to play. This was mostly as a favor to the director and the club. Many of my partners were not strong players, and we rarely did well, but they usually enjoyed partnering a decent player who could hold his temper at the table. Further, when playing in these games I would try to just play a "solid game of bridge" rather than using tactics to turn the hands (and other such stuff that a strong player can do to carry a weak partner in). After all, the main goal was that partner have a good time.

 

If doing this would adversely effect my rating, I would probably not have volunteered. This is especially true if ratings are used for something (for example, if a low rating made it hard for me to be eligible for top flight events).

 

This is a serious concern -- being able to find a short-term partnership does contribute to getting many people out to a game.

Almost all my bridge is played like that (or at least almost all of it that contributes to the NGS) - partnering whoever turns up, to make up the numbers. And now I discover it's been used over the past couple of years to create my rating, but it doesn't seem to have given me an unreasonable grading - in fact my largest increases have come about after partnering some of the weakest players. So, although there's the possibility of opting out, I don't think I will. Probably my grading will fluctuate more than most, but I think it will add to the interest.

[gnasher]

But I disagree that attendance at duplicates and congresses by only the better players is a good thing.

Did anyone say it was?

 

I suggested that it was OK to "discourage people who care about their rating but not about how well they actually play", but that's rather different. In fact, a discussion of that category of player (of whom there are not, I suspect, very many) seemed to fit well with your comment about "arses on chairs".