How to define an expert

[DrTodd13]

In tourneys you may play against all comers but in the MBC I would venture to say that most play is within one self-rated level. Any rating system cannot possibly be accurate unless it takes into account the skill of the people involved and the expected outcome. The Lehman system used on BBO does it this way. The Lehman system isn't perfect but it is reasonably accurate. The problem with this rating system is not how accurate it is but the effect of having a rating system in place on how people behave.

[paulg]

In tourneys you may play against all comers but in the MBC I would venture to say that most play is within one self-rated level.  Any rating system cannot possibly be accurate unless it takes into account the skill of the people involved and the expected outcome.  The Lehman system used on BBO does it this way.  The Lehman system isn't perfect but it is reasonably accurate.  The problem with this rating system is not how accurate it is but the effect of having a rating system in place on how people behave.

1,$s/BBO/OKB/g

 

And you have expressed the crux of the problem well.

[bid_em_up]

bid_em_up Posted on Oct 9 2006, 12:49 PM

 

The averages kept by no means reflect how well you are playing. If I sit and play 1000 hands vs. the best BBO has to offer and maintain an IMP rating of 0.00 (average), and someone else sits and plays vs. beginners/novices/intermediates and maintains the same 0.00 average, who do you think the better player is?

 

OK, I lied when I said no more post on the subject. But .. the above statement is simply not true.

 

Evidently you do not understand the true nature of the game of bridge. As much as we fancy the game to be one of pure skill, there is a HUGE element of luck involved in duplicate bridge. Sure, the best players win most of the time at all levels, but on any given set of boards, the worst pair in the world can beat the best pair. Ever wonder why the same players come out on top all the time. Much of the reason for that is that the same players show up at the competitions. The real best player in the world is probably some overworked, underpaid person that never earned one Masters Point in their life. What is the most important attribute for a World Class player to possess. I would say it is money or a sponser with deep pockets. There are 1000's of Life Masters around that got their ranking by simply showing up enough times and still can't play a lick.

 

Given the settings you describe. it would be difficult or impossible to tell who the best players are just based on averages. That point I happily concede to you. Do the players playing the "best BBO has to offer" lose by a lot or by a little? Do the players playing the novices get beat by bad bids getting lucky? But does it matter at the extremes? NOT ONLY NO, BUT HELL NO... if you are always playing in a group of top flight players you need NO rating for the price of admission. If you are always playing against novices, you also need no rating to be admitted to the game .. they are just happy to have ANYONE play with them.

 

But, in between, are 90% of the players that play against all comers and for them the averages are a meaningful indicator of how a player is perfoming.

 

:D Wayne

Its not true? Prove it to be false then. You cant. However, I can show (and did) show you why your position simply does not work.

 

You think other people havent thought of this very same idea (most, if not all, of the forum users are fully aware of the myhands page). Try spouting something original next time.

 

I can show many other reasons why it doesnt work. I can sit down and beat up on random comers all day long. My expected IMP ratio is somewhere around 0.75 imps/bd or more. Does this reflect my level of play? Not in the least. It simply shows I can beat up on beginners/intermediates or whatever. Give me a regular partner and the expected IMP ratio just increases.

 

Is luck involved? To quote you, NOT ONLY NO, BUT HELL NO. If you think it is, you are living in a dreamworld. There is no luck involved in doubling weak opponents in poor contracts, or making contracts (hopeless or otherwise) thru poor defense. Again, this is not a factor in a players skill level. Unless, of course, you just consider it lucky to draw such poor opponents (or you just deliberately select them).

 

The whole point is/was that there is not a way to create an accurate (or reasonable) rating system unless you also take into account the levels of partner and opponents as well.

 

BTW, the best player in the world drives a limo in NYC. He does have masterpoints, though.....LOL (and no, I am not referring to myself).

[awm]

There are several points being made here. To respond to each of them:

 

(1) Yes, looking at MyHands is a good way to figure out where you are losing IMPs/MPs, and learn from your mistakes.

 

(2) If everyone played with random partners against random opponents in the main bridge club, then MyHands would present a reasonably accurate measure of skill level once sufficient boards have been played. At least, this would be true for the majority of players. It will be hard to distinguish between say expert and world class though, because at this level the mistakes made by others at the table will tend to dominate the score (they will both be very above average though).

 

(3) In fact, if you sit down at the table and get a random partner, it's probably a reasonable bet that he or she has played a bunch of hands with random partners, and then you can apply the reasoning above. You can also look at myhands and try to filter out frequent regular partners if you like.

 

(4) On the other hand, this process doesn't work for everyone. If you play mostly with/against friends, then the myhands rating can only reflect how you do against those people. Many of the star players play almost exclusively with and against other star players. Obviously some of them will come out of this with negative IMP totals. This doesn't mean that playing against the BBO population "at random" they will be negative.

 

(5) Beating up on bad players and doing well against good players are actually different skills. For example, there's a fellow in my local club who wins extremely frequently. He's always near the top of the leaderboard. However, if you look at his board results, he gets tops or near tops almost every time against the weakest players in the club and rarely has an above-average round against the strong pairs. There are many other players who play at the same club and do consistently well against regional/national level competition. This fellow doesn't do well in those fields.

 

(6) Implementing an accurate rating system for pairs is actually fairly straightforward. Implementing a similar system for individuals is remarkably difficult. There are a number of professional mathematicians/statisticians studying this sort of problem.

 

(7) Making ratings "visible to the world" can have substantial negative social effects, especially if the rating system is not perfectly designed (which it won't be, because we don't know how to design a perfect individual rating system). In particular it tends to discourage people from playing with weaker partners or against stronger players for fear that their rating will go down. OKbridge did this, and this phenomenon was very much observable.

[Wayne_LV]

  

[Rain]

Use bm2k. I keep repeating this but I never get tired of it.

 

Those who can't even complete level 2/3 have no business calling themselves advanced or experts.

 

Anyways it doesn't matter much if everyone likes to think of himself as expert. He can think what he wants, I can think what I want, and enjoy my private malicious chuckle when he gets thumped.

[Wayne_LV]

   

[bid_em_up]

You obviously cant read either.....

 

What I said was....... slowly for the ones who cant read.....

 

I can sit down and beat up on random comers all day long. My expected IMP ratio is somewhere around 0.75 imps/bd or more.

 

Big difference between what I play actually play against and just any random bbo opponents.

 

So it shows I am playing average bridge.....but at a much higher level than yourself. It also doesnt reflect that I played many hands with an intermediate partner or that if you play against real experts, and are one yourself, then your expected ratio is 0.00. You apparently can't comprehend these small, but true facts.

 

Try doing your homework instead....I have looked at who you play with and against. Not one known name......

 

There is a definite corrolation between a one month running average win/loss record on BBO and how a player is performing at the table.

 

No there is not. Believe what you will.......

 

In your infinite wisdom, lets suppose the following players tried to sit @ your table using your rating system.

 

player #1) 1 month average = 0.30

player #2) 1 month average = 0.59

player #3) 1 month average = 0.58

 

Who would you want to take as your partner?

 

Which one would you expect to be better?

 

I'll give you a hint......player #1 is Benito Garozzo.

 

Hmmm, whats that you say?

 

And if you consider a typical BBO field to be an above average field.....I dont think I really need to say anything else. 'Cause if I do, I'm liable to be banned from the forums. :D

[Wayne_LV]

   

[EricK]

I've thought of a reasonable way that a computer can estimate (or at least rank) the strength of players:

 

On a double dummy basis, how many tricks on average do they blow with their opening lead?

 

Here is something which is perfectly measurable, does not depend very much on who one's partner is, is immune to the problem of people abandoning boards (as it can be measured after 1 card has been played even on abandoned boards) and will not discourage people from pairing up with weaker players for fear of lowering their rating.

 

Obviously there is more to bridge than the opening lead, but there must surely be a good correlation there.

[awm]

I've thought of a reasonable way that a computer can estimate (or at least rank) the strength of players:

 

On a double dummy basis, how many tricks on average do they blow with their opening lead?

 

Here is something which is perfectly measurable, does not depend very much on who one's partner is, is immune to the problem of people abandoning boards (as it can be measured after 1 card has been played even on abandoned boards) and will not discourage people from pairing up with weaker players for fear of lowering their rating.

 

Obviously there is more to bridge than the opening lead, but there must surely be a good correlation there.

I'd be interested in seeing this rating, just to see how good people are on opening lead. I suspect that a lot of pretty good players actually make a lot of bad leads... it's one of the hardest parts of the game after all.

[bid_em_up]

I do not know how I can explain it any better than I already have, but I will try one last time.

 

I am NOT proposing a rating sytem at all. The self rating system can remain intact in all of its glory.

 

What I am proposing is that BBO simply compute a running average based on the past 1 months hand records that ALREADY exist and if the number of hands is sufficient to produce a meaningful average (100-500) .. pick a number .... and display that average on the players profile.

 

And as far as which player I would choose from your list ... with those numbers I would be happy to play with any of them.

 

And as far as me not playing with big name players .. I am sorry but I do not know any big name players. This remark epitomizes what I dispise about BRIDGE SNOBS. You think if a player does not rub elbows with the top 10 players on the ACBL Top 500 list that they are not good players? And you probably think if a player does not play 2 dozen conventions that they must not be very good. Most conventions are gee whiz and give a pair such a small % edge on a few obscure hands that all you need do is screw up the bidding on one of them once a year and you have negated all the edge they are suppose to give. I do, however, play Reverse Rusinow LOL.

 

Yep, I play with a lot of unknown players ... many of them are taking free lessons from me and believe me, playing with them often does not help my averages. What qualifications do I present for teaching bridge. Well not a lot, except I DO know the basics of the game extremely well and love to see casual players learn to bid hands correctly and learn basic declarer play and defense. That gives me far more pleasure than the quest for Masters Points.

 

And I aplogize to everyone that has followed this thread for letting it degnerate into what sounds more like a political campaign than a discussion among intelligent beings.

 

I have learned my lesson and do not intend to ever post on this forum again. I have been reminded why I do not like ACBL bridge clubs and most bridge players in general.

 

 

:D Wayne

Wayne,

 

While my initial thought was.....dont let the door hit you in the butt on the way out......

 

Please, you are taking things way too personally. You had what you thought was a good idea. I have simply tried to explain why it isnt as good as it sounds. Sorry if that makes you upset. I have understood what you were suggesting from the first time you posted it.

 

All of the forum posters (I would like to include myself) usually are very helpful when asked questions. We volunteer our time because we want to help others. You can get some good advice/information here, and for the most part, the forum posters are a friendly bunch.

 

But that does not mean we will pacify you or be agreeable in every post. If your logic is flawed, how else are you going to realize it is flawed unless it is pointed out to you?

 

The average score for the last month does not reflect how well a player has played for the last month. There are too many other factors involved. I have tried to point out just a few of the reasons in an attempt to explain why it doesnt work. There was a time when I thought the same as you....until I did more research into it and gave it more thought. You are not the first to suggest this, nor will you be the last......but that still doesnt change the flaws in the suggestion.

 

As far as being a bridge snob goes, I am probably one of the farthest things from it. I will play with just about any one who truly wishes to learn, assuming I have the time to do so when they ask.

 

And what is one of the great things about BBO is that many of the top players are willing to allow us "nobodies" into their games at least occasionally, and in many cases, they will continue to play with/against you. They are also willing to help players along in most cases. Try it and see.

 

There are many conventions that I do not know, nor do I care to. I usually play a very simple 2/1 scheme, without a lot of gadgets. A false assumption on your part that I must play a wide variety of conventions. I couldnt begin to tell you who the top 10 players are in the Top 500....nor do I really care. Another false assumption on your part.

 

I havent even begun to address your earlier post about pairs who had such a high average that they must be cheating. Since I do not know who you refer to, I cannot fairly judge for myself whether they were or not. But a high monthly IMP or MP score, in and of itself, means absolutely nothing.

 

I was not attempting to point out the fact that I may play with/against top players. (Ok, maybe I was, but only as part of trying to explain the differences in competition levels and you had pissed me off by insulting me directly).

 

You are/were attempting to claim that by showing someones monthly average, you could get a good feeling as to how well they are playing or how "good" they are. This is effectively saying that someone who has monthly average of 0.10 (pick a number) must be as good as or plays at the same level as another player with the same number who plays against much better (or weaker) competition over the course of the prior month. Or that the expert player who has a negative rating must not be any good, without taking into account that he played 300 boards with a novice or intermediate or played 200 boards against top flight competition. It just does not hold water. Sorry.

 

Oh, and one last thing.....if you want a discussion between intelligent beings, try to be a little less insulting in your posts. You have effectively called me a snob, an average player (based on a meaningless monthly rating), gotten defensive when errors about why the posting of this information on a profile is not a good idea are pointed out to you without providing any contrary information or facts.......and now finally, in a huff, storm off in an attempt to claim that you cannot get a discussion between intelligent beings. Well, obviously not.

 

You could instead try to convince me otherwise by giving a rational and intelligent response. But you havent done so. Instead, you just keep telling me (us, the forum users) that "BBO could simply compute a running average based on the past 1 months hand records that ALREADY exist and if the number of hands is sufficient to produce a meaningful average (100-500) .. pick a number .... and display that average on the players profile".

 

Believe what you wish......and thanks for the suggestion. :)

[cicus]

Perhaps a better solution is to reduce the categories available to simply: World Class/ Non-World Class.

 

World Class would be easier to manage, as the names of those who have represented their countries in World events are recorded somewhere - everyone else falls under the next umbrella.

We already have that: stars or no stars

I don't know upon what awarding stars is based but I know all players with a star in my country and there are big differences in their pllaying skills. So for me star-no star is not a very good distinction. I think a star should be world class.

[Free]

The real world class players are generally known by name. So look at their profiles and you know if you have a real WC player. However, the star is still an indication that the player has some potential, but it indeed doesn't indicate you have a real WC...

[matmat]

There are two numbers that I would like to see for a partner, which albeit statistical do not measure the player's ability directly:

 

1) # deals played per partner.

A player who can't hold onto a partner is likely not that great and probably not someone I would like to play with. I'd expect that true advanced players and experts that take the game more seriously would have higher numbers here.

2) # of deals abandoned

Someone who misbids or misplays and runs is not someone I'd like to play with either and this stat is also probably a measure of a player's approach to the game

[32519]

Expert: Someone who has enjoyed success in major national tournaments.

 

This definition, as stated in Rules of this Site, may be flawed, but you don't get much closer than that in my opinion. As Frances points out, we have loads of members who rate themselves as experts although they haven't won anything significant.

 

Roland

After reading this thread, I’m not entirely convinced with everything said here. My current F2F partner has excellent bridge savvy, logic, flair and very often bidding (and making) 3NT contracts on an outright gamble that the opponents are going to start off the defence with a) either the wrong suit, or, b) the wrong card in a suit. Yet her general (overall) knowledge of the game is extremely low when measured against the plethora of systems/conventions/methods of signalling etc. Yet she has won a number of regional red point events (with different partners) on raw talent alone.

 

So how does one really define an expert? Roland’s post above is certainly a yardstick.

[lamford]

An expert is a man who has made all the mistakes which can be made, in a narrow field. - Niels Bohr

[jogs]

Bob Hamman stated, "An expert makes 2 mistakes on every hand.". I firmly believe that.

 

For the 1970 world championship one writer wrote a review on the boards. He nitpicked every marginal error. Best bridge book ever written. He made so many enemies, he was never allowed to report on the championships again.

[PhilKing]

An expert is a man who has made all the mistakes which can be made, in a narrow field. - Niels Bohr

 

 

That sounds like Matthew Upson when he was at West Ham.

[dwar0123]

After reading this thread, I’m not entirely convinced with everything said here. My current F2F partner has excellent bridge savvy, logic, flair and very often bidding (and making) 3NT contracts on an outright gamble that the opponents are going to start off the defence with a) either the wrong suit, or, b) the wrong card in a suit. Yet her general (overall) knowledge of the game is extremely low when measured against the plethora of systems/conventions/methods of signalling etc. Yet she has won a number of regional red point events (with different partners) on raw talent alone.

 

So how does one really define an expert? Roland’s post above is certainly a yardstick.

Raw talent does not an expert make.

 

Combine that raw talent with a plethora of system/conventions/methods of signaling and win a number of unlimited regional gold point events.

 

Really just win a number of unlimited regional gold point events.

[bluecalm]

For the 1970 world championship one writer wrote a review on the boards. He nitpicked every marginal error. Best bridge book ever written. He made so many enemies, he was never allowed to report on the championships again.

 

Interesting.

Author/title ?

[mgoetze]

I will reiterate a suggestion I made many months ago in the "Suggestions for the Software" forum: display peoples' average MP result in robodupes on their profile.

[dwar0123]

I will reiterate a suggestion I made many months ago in the "Suggestions for the Software" forum: display peoples' average MP result in robodupes on their profile.

How would you break down the different ranks based on that stat?

[mgoetze]

How would you break down the different ranks based on that stat?

I haven't given it much thought and would be happy enough with the raw numbers, but perhaps

 

Over 58%: Expert

54%-58%: Advanced

46%-54%: Intermediate

42%-46%: Beginner

Below 42%: Novice

 

Of course playing with GIB specifically is something that can be trained, an expert who specifically exploits GIB's weaknesses will do better than one who has never played with GIB before. But I think this stat would be somewhat useful all the same.

[CSGibson]

The real question is: Why do you feel the need to define an expert?