[jtfanclub]

uday, on Aug 16 2007, 12:52 PM, said:

Then perhaps the teams that lost to the winners in head to head play, and no one else, should compete amongst themselves for 2nd place.

Hmmm...suppose their were 5 rounds, of KO. The last round is double length.

After two rounds, for each team A still in the running, have the team who lost to team A in round 1 play the team who lost to team A in round 2.

After round 4, have the team who lost to team A in round 3 play the team who lost to A in round 4.

Then have the winner of the 1-2 losers play the winner of the 3-4 losers.

And finally, after the KO is over, have the finals loser play the winner of the 'defeated by A' guys.

I think that sounded more complicated than it is. Example, in which the higher letter always beats the lower letter, but the seeding is reversed, so that the two best teams meet in the first round. ' shows the number of losses, including that round.

Round 1:
A defeats B'

Round 2:
A defeats C'

Round 3:
A defeats D', and B' defeats C''

Round 4:
A defeats E'

Round 5, part 1
A plays F, D' defeats E''

Round 5, part 2
A defeats F, B' defeats D''

Consolation Round
B' defeats F''

A is USA1, B is USA2.

Of course, this means an awful lot of people who never played A will end up playing consolation rounds for nothing when the team that knocked them out gets knocked out themselves.

[jdonn]

pclayton, on Aug 16 2007, 01:48 PM, said:

I agree with Justin that the two semi-finalists have the opportunity to play each other and then meet the loser to USA1 in the final for USA2.

I just got the idea of sort of a comprimise suggestion between that and what Uday suggested, just throwing it out there. Go with your suggestion, but if the second place match is a rematch of one of the semifinal matches then include either a full or partial carryover based on the outcome of the semifinal. That way you can't beat a team by 100 the first time, lose by 1 the second time, and have them be chosen over you. It would have an added bonus (well I consider it a bonus but others may not) that the intergrity of the last portion of a semifinal blowout would be preserved, as a team losing by a ton wouldn't start either wildly swinging or simply trying less hard.

I admit it seems strange to make the match for US 2 potentially longer than the match for US 1, but that doesn't bother me as long as the match for US 1 is sufficiently long in the first place. Perhaps the answer is a 50% carryover and make the second match half as long as the match for US 1, which effectively makes the matches the same length.

In the case where the match for US 2 is not a rematch of the semifinals, then it is the same as Uday's suggestion anyway as it's the last two teams that got beat by the winner.

Any thoughts?

[mike777]

If you are going to do all of this, why not just have two trials with seeding and byes.

Sure there may be a bit more expense but so? We are here to play bridge and have fun yes, not pinch pennies?

If the number one goal is too save money start having tourneys on the web with proctors.
Reduce, Hotel, airfare, dining out expenses.

[barmar]

mike777, on Aug 16 2007, 02:23 PM, said:

If you are going to do all of this, why not just have two trials with seeding and byes.

Isn't that what we currently have? BB is every other year, and we have a trial each year. The winner the first year is USA1, the winner the second year (which USA1 doesn't play in) is USA2.

Or am I thinking of something else?

[keylime]

I think having as few of byes possible is best for the entire event. One of the buggers about the USBF system are the 8 byes given. I strongly prefer 4 byes (or less - why not slog your way through it instead?)

I like the curling method of playoffs myself (called the Page method if memory serves) - during my time in Nanaimo the Vancouver Bridge League used it and I thought it was quite rational and balanced. It allows for the number 1 team to go to the finals yet does allow for a high seeded team to lose a match and still recover to win the entire event.

[barmar]

hrothgar, on Aug 16 2007, 01:57 PM, said:

Obviously, a good seeding system will decrease the chance that this happens. Then again, if you're that confident in your seeding system, there really isn't any reason to have a tournament. Just select your number 1 and number 2 seeds.

Well, if you take that to its logical conclusion you'll never play any games, you'll just decide all tournaments by looking at everyone's seeding points.

Seeding is a rough estimate of the ranks of the teams based on history, and then the actual play is used to refine and update it with current data. The basic assumption on which this is based is that players' abilities and team rankings change gradually, and we're mostly concerned with the top-ranked teams. For instance, if the only error in the seeding is 1st vs. 2nd place, and everyone plays according to form, these two teams should meet each other in the final and then the error will be corrected. On the other hand, if the error is between the two lowest teams, it won't be corrected -- they'll both lose their first matches, and there's no playoffs in the early rounds to discover their relative ranks.

When I was in high school or college I read a book of essays by Charles Dodgson, AKA Lewis Carroll. Although he's best remembered as the author of the Alice in Wonderland books, he was primarily a mathematician and logician. I don't remember the details, but one of the essays was on how best to structure a tennis tournament. I did some googling, and I haven't been able to find the text of the essay online, it was titled "Lawn Tennis Tournament" and published in 1883.

[JanM]

Wow! Thanks for all the thoughts. If I can figure out how to quote several things in one reply, I'll try to answer as many questions as I can and see whether you can help some more

barmar said:

mike777, on Aug 16 2007, 02:23 PM, said:

If you are going to do all of this, why not just have two trials with seeding and byes.

Isn't that what we currently have? BB is every other year, and we have a trial each year. The winner the first year is USA1, the winner the second year (which USA1 doesn't play in) is USA2.
Or am I thinking of something else?

In 2008, the USBC winner will be the only US team in the Olympiad. Therefore we have only one USBC to select both teams for 2009.

jlall, said:

I would have the losers of the semi final match play while the finals were going on. Winner of finals=USA 1. The loser of the finals plays the winner of the the match between the losing semi finalists. The winner of this match is USA2.

That's how we do it for the Women. But there is fairly strong feeling that we have too many strong teams in the Open to start the Repechage with the Semi-final losers, so we're trying to come up with something that lets earlier losers get back in without making the whole event too long.

uday said:

I'm sure I don't know what I'm talking about but if we assume that

any team beaten by the winner is a candidate for 2nd strongest team (in this event)
any team beaten by any other team is not.

Then perhaps the teams that lost to the winners in head to head play, and no one else, should compete amongst themselves for 2nd place.

That makes a lot of sense, except for the problem someone pointed out later that it means we either have to wait to start the USA2 bracket until the USA1 winner is decided or play a lot of irrelevant matches.

awm said:

Run a double-elimination event. The team that goes undefeated is USA1. The team that ends with one loss is USA2. Constructing this can be a bit complex, but should be possible. Allowing byes actually makes this easier to construct, and it removes the luck factor of playing the best (winning) team in an early round.

That's sort of what we're looking at, but it's not as easy as it sounds - the problem is that we want the two events to run side by side and teams keep dropping into the USA2 bracket, so the matches have to be different lengths, and where do you start (IOW, which losers first get into the USA2 bracket). Before continuing to struggle with numbers of teams and lengths of matches, I was wondering if anyone might come up with a better suggestion

hrothgar said:

With this said and done, I’m not sure whether it would be worth doing the necessary work. My impression of the USBF is that subjective considerations outweigh objective criteria.

I guess that depends on what you mean by subjective and objective. If you mean that we're not likely to be swayed by mathematical models that conflict with our impressions of what has worked in the past, you're right. The reason that you would have a hard time convincing me that a single elimination KO is "better" than a RR followed by a KO is because my experience convinces me that seeding isn't anywhere close to perfect, and the first round of a KO is going to be very strongly influenced by seeding. Maybe I'm wrong, but a lot of people seem to agree with me, even some who disagree with me on almost everything else.
With regard to conventions, I think you've misunderstood me - the reason that we don't use the WBF rules is that most of our players are more familiar with ACBL rules and we aren't willing to force them to comply with a slightly different, not necessarily better, set of rules for the USBC. Of course, the winners (and maybe a second team) will have to comply with those rules for the WBF event, but they'll have a captain and coach to help with that, as well as a few months to work on it at a time when they know it will be relevant for them.

hrothgar said:

In short, if you can provide a very specific description regarding the set of constraints, I think that folks can identify the most accurate tournament. Absent this type of description, the problem isn’t an attractive one to work on.

I don't know what sort of constraints you mean, but basically:
The USA1 bracket is going to look like this year's USBC (maybe some matches might be shorter because they don't completely eliminate anyone.
USA2 needs to be chosen in an event that runs parallel to USA1 and where USA1 losers drop into it. A double elimination KO if you want to call it that, but some other format might be possible.
The USA2 event would ideally end no more than 3 days after the USA1 finals (because of fatigue for the players mainly).

ABERLOUR10 said:

Runner up & both semifinalists play a long "3-teams-match"
(with carry over for the runner up)

That's how we did it in 2001, and despite the excellent result (USA2 won the Bermuda Bowl that year in case you've forgotten), there was a very strong feeling that this wasn't a good format and I don't think there is any chance that we will use a 3-way again

pclayton said:

The qualifying should mirror the actual event, so I'm not a big fan of byes. Stamina should be a big factor in team selection, and if a team gets a free ride to the semi-finals, then stamina doesn't play nearly the factor that it should.
I'm also very skeptical about augmentation. If four (or even 5) warhorses grind it through and somehow gain one of the spots, I can see putting the two seats on the open market and letting someone buy their way onto our national team. Isn't that possible? Or does the USBF have a say-so in who is allowed to be added?

As to byes, there's a very strong opinion that the three major KOs during the year should be "part" of the USBC, which is achieved by the bye structure. That gets debated periodically but so far the "Byes" have it. As to augmentation, the USBF has to approve augmentees and we have strict rules and a very strong Credentials Committee who review any proposed augmentees, to avoid augmentation of someone who is not as good as the rest of the players on the team. So far it seems to be working and I certainly hope that will continue to be the case.

Mike777 said:

It seems for the past few years or decade, the USBF has done a good job in letting us nobodies have a shot, but rewarding the better teams for regular season performance.

I agree with you and I think that our basic approach is a good one. But every fourth year, we have to choose 2 teams, and that's our current issue.

[hrothgar]

JanM, on Aug 17 2007, 01:30 AM, said:

I guess that depends on what you mean by subjective and objective. If you mean that we're not likely to be swayed by mathematical models that conflict with our impressions of what has worked in the past, you're right. The reason that you would have a hard time convincing me that a single elimination KO is "better" than a RR followed by a KO is because my experience convinces me that seeding isn't anywhere close to perfect, and the first round of a KO is going to be very strongly influenced by seeding. Maybe I'm wrong, but a lot of people seem to agree with me, even some who disagree with me on almost everything else.

The easiest way to proceed would be to compare two different formats:

1. A single elimination with no seeding

2. A round robin that reduced to a single elimination (using the RR results to seed the KO)

If the single elimination KO wins without seeding...

Few parameters that I'd need to create an accurate model.

How many teams do you anticipate entering the event?

How much time do you expect to be able to allocate for the event?

What is the average amount of time necessary to complete a board?

Can you make a reasonable guess about the shape of PDF describing the strength of the various teams? (Uniform? Normal? Bimodal? Something exotic?)

[JanM]

hrothgar, on Aug 16 2007, 05:41 PM, said:

Few parameters that I'd need to create an accurate model.

How many teams do you anticipate entering the event?

How much time do you expect to be able to allocate for the event?

What is the average amount of time necessary to complete a board?

Can you make a reasonable guess about the shape of PDF describing the strength of the various teams? (Uniform? Normal? Bimodal? Something exotic?)

I think that between 25 and 30 teams will enter, probably closer to 25.
A one-winner event now takes 11 days. I think we're looking at no more than 14 for a 2-winner event, and hopefully 12 or 13.
We allow 9 minutes per board. I know that seems high, but somehow it doesn't seem to be in practice.
That's hard - for one thing, I'm not sure what your different models are, and for another it's very hard to analyze the strengths of teams. Most of them played this year and last, and you can see the scores on the usbf website, but I don't know if that's an appropriate method to evaluate or not.

[mike777]

It is 2007. We need to pick two teams for late 2009? We have picked zero so far.

Why not just have two trials if almost everyone does not like the simple suggestion of Justin's?

Justin's saves money. Two trials spends more money.

One in 2008 and one in 2009?

[cherdano]

Richard, I would be curious about the results of your simulations (but maybe in another thread, as this isn't really relevant for the question of this thread). Why don't you just assume a normal distribution with a standard deviation of s.th. like 0.3 IMPs (or maybe try several values), 25 teams, and 600 boards (the last trials used 60 boards a day).

[JanM]

mike777, on Aug 16 2007, 06:01 PM, said:

It is 2007. We need to pick two teams for late 2009? We have picked zero so far.

Why not just have two trials if almost everyone does not like the simple suggestion of Justin's?

Justin's saves money. Two trials spends more money.

One in 2008 and one in 2009?

Because the 2008 USBC will pick our Olympiad team.

[mike777]

JanM, on Aug 16 2007, 06:18 PM, said:

mike777, on Aug 16 2007, 06:01 PM, said:

It is 2007. We need to pick two teams for late 2009? We have picked zero so far.

Why not just have two trials if almost everyone does not like the simple suggestion of Justin's?

Justin's saves money. Two trials spends more money.

One in 2008 and one in 2009?

Because the 2008 USBC will pick our Olympiad team.

Again so why not two trials in 2008? One early for 2008(olympiad) and one later in 2008 for 2009(usa1)? Have a third trial in 2009 for usa2.

Again if money is the main issue then Justin's idea as used already in the Womens seems cheapest and fairest.

I am a bit lost on what the main number one priority is....saving money or other?

[cherdano]

JanM, on Aug 16 2007, 04:30 PM, said:

awm said:

Run a double-elimination event. The team that goes undefeated is USA1. The team that ends with one loss is USA2. Constructing this can be a bit complex, but should be possible. Allowing byes actually makes this easier to construct, and it removes the luck factor of playing the best (winning) team in an early round.

That's sort of what we're looking at, but it's not as easy as it sounds - the problem is that we want the two events to run side by side and teams keep dropping into the USA2 bracket, so the matches have to be different lengths, and where do you start (IOW, which losers first get into the USA2 bracket). Before continuing to struggle with numbers of teams and lengths of matches, I was wondering if anyone might come up with a better suggestion

Assuming you don't want to touch your rules about byes, I doubt there is a good solution, unless you are willing to have some 3-ways early in the loser's bracket, or round-robin-among-5-with-two-teams-advancing, etc.. E.g. if you would start the losers bracket with the losers of the "round of 8" (usually 6 teams playing), you could have a 3-way among the 3 losers with two survivors, who then join the losers of the semifinals for a 3-day knockout. The winner of that will then play against the loser of the finals for the second berth (who will have had a one-day break after losing the final).
I am sure this is the kind of suggestion you came up with yourself, so...I think it's just a matter of which kind of mess in the loser's bracket to live with. (Oh, and of course some rules about carry-overs in case of replays in the loser bracket.)

[JanM]

mike777, on Aug 16 2007, 06:38 PM, said:

JanM, on Aug 16 2007, 06:18 PM, said:

mike777, on Aug 16 2007, 06:01 PM, said:

It is 2007. We need to pick two teams for late 2009? We have picked zero so far.

Why not just have two trials if almost everyone does not like the simple suggestion of Justin's?

Justin's saves money. Two trials spends more money.

One in 2008 and one in 2009?

Because the 2008 USBC will pick our Olympiad team.

Again so why not two trials in 2008? One early for 2008(olympiad) and one later in 2008 for 2009(usa1)? Have a third trial in 2009 for usa2.

Again if money is the main issue then Justin's idea as used already in the Womens seems cheapest and fairest.

I am a bit lost on what the main number one priority is....saving money or other?

There are some players who think one Trials every year is too many (we're currently asking for opinions on that from the players). I think there is about a 0% chance of selling the idea of 2, even if that made sense. And I'm pretty sure it doesn't - one of the objections to what we do in the Rosenblum year (select USA1 for the following year's BB in a USBC held later than normal in the year) is that there's too much time between selecting the team and the team playing in the BB. That might be okay when the alternative is not to hold the USBC that year, but not when there's already a USBC that year.
The issue isn't money, it's time - there are already a lot of bridge events on the calendar. There really isn't room for another. Note that we can hold the Rosenblum year USBC late because the World Championships are held early. In 2008, the Olympiad is likely to be in the early fall.

[mike777]

Interesting, thanks for your comments.

I am speechless when I hear that someother bridge event in a 52 week year would overtake trying to play as USA 2 in a second trials but ........
I would have guessed people in the USA would drop just about anything to jump at chance to play as USA2. Especially if it means no one else shows up....

Pros get paid for another event, sponsors have another shot at glory at a cost that is close to zero for them. Nobodies have a shot since no one else shows up..seem perfect.

I must say no time would have been my last guess as for a reason to not hold a second trial for usa2.

[uday]

OK, what about another uneducated guess?

We're already trusting the seeding (or points, or whatever it is that grants byes). Why not trust it further, and split the field into two brackets, one spearheaded by seed1, and the other by seed2, run the brackets independently of each other, and take the 2 winners?

[JanM]

uday, on Aug 16 2007, 07:30 PM, said:

OK, what about another uneducated guess?

We're already trusting the seeding (or points, or whatever it is that grants byes). Why not trust it further, and split the field into two brackets, one spearheaded by seed1, and the other by seed2, run the brackets independently of each other, and take the 2 winners?

That's a fascinating idea - I'll "run it up the flag pole"

[jdonn]

uday, on Aug 16 2007, 07:30 PM, said:

OK, what about another uneducated guess?

We're already trusting the seeding (or points, or whatever it is that grants byes). Why not trust it further, and split the field into two brackets, one spearheaded by seed1, and the other by seed2, run the brackets independently of each other, and take the 2 winners?

I don't think that one would fly at all. I think you were onto something much better with your first idea. It seems an absolute necessity, if using any sort of round robin format, to have every team play every team.

[JanM]

mike777, on Aug 16 2007, 07:23 PM, said:

Pros get paid for another event, sponsors have another shot at glory at a cost that is close to zero for them. Nobodies have a shot since no one else shows up..seem perfect.

Another Trials would be far from free, for anyone - the players who'd have to take the time out of their schedules, pay for plane, hotel, meals, etc; the sponsors who'd ditto plus pay the pros; the USBF volunteers who are already stretched pretty thin. It's just not going to happen.