Rating floor but no rating

[nolan]

The big difference is that your ‘play up’ policy is optional, so it’s the player’s choice to play up. A ‘higher of official or unofficial rating’ policy would not make it the player’s choice, which is when problems can start to occur.

And as a reminder, under US Chess rules, unofficial ratings can ONLY be used if they are higher than the player’s current published rating. In over 30 years of experience as a TD and as the programmer of the ratings system, I think I have seen only one case where it made much sense to even think about using a player’s lower unofficial rating over his published rating, and that was a case where the published rating was clearly inaccurate.

[scottrparker]

@nolan

The big difference is that your ‘play up’ policy is optional, so it’s the player’s choice to play up. A ‘higher of official or unofficial rating’ policy would not make it the player’s choice, which is when problems can start to occur.

And as a reminder, under US Chess rules, unofficial ratings can ONLY be used if they are higher than the player’s current published rating. In over 30 years of experience as a TD and as the programmer of the ratings system, I think I have seen only one case where it made much sense to even think about using a player’s lower unofficial rating over his published rating, and that was a case where the published rating was clearly inaccurate.

You can use latest unofficial ratings instead of official ratings like Micah Smith is doing as long as you announce in advance that you are going to be doing so. You can vary from standard rules quite a bit as long as you announce in advance what your variances will be. I ran a few tournaments using the McMahon Swiss pairing system, and had no issues with getting them rated by US Chess.

[relyea]

@scottrparker

You can use latest unofficial ratings instead of official ratings like Micah Smith is doing as long as you announce in advance that you are going to be doing so. You can vary from standard rules quite a bit as long as you announce in advance what your variances will be. I ran a few tournaments using the McMahon Swiss pairing system, and had no issues with getting them rated by US Chess.

And do you really think this is a good idea?

Alex Relyea

[scottrparker]

@relyea

@scottrparker

You can use latest unofficial ratings instead of official ratings like Micah Smith is doing as long as you announce in advance that you are going to be doing so. You can vary from standard rules quite a bit as long as you announce in advance what your variances will be. I ran a few tournaments using the McMahon Swiss pairing system, and had no issues with getting them rated by US Chess.

And do you really think this is a good idea?

Alex Relyea

Within broad limits I’m in favor of letting an organizer structure his tournament just about any way he wants to as long as he clearly announces in advance what he is doing. Chess players will vote with their feet, and if people don’t like the organizer’s ideas they won’t enter his tournament.

[nolan]

Rule 28E1 does not provide for using an unofficial rating lower than a player’s published rating. The exceptions in 28E2 are all justifications for using a higher rating than the player’s current published rating.

It is not clear to me that this is a rule that can be relaxed at all, much less without full advance publicity and an on-site announcement, including the possibility of a player being assigned a rating below that player’s current published rating.

This is another place where the rulebook could use updating to make it clear what the TD/organizer can and cannot do.

[sloan]

@nolan

About the only place that unofficial ratings make sense are in low-stakes events that have a high percentage of young rapidly-improving players in them.

A long, long time ago, we used to run weekly summer scholastic quads. We always did a private calculation of ratings changes to place players in quads. Waiting for a printed ratings supplement was not a reasonable plan.

[Smythe_Dakota]

@Micah Smith

… I emailed the US Chess ratings manager last Thursday and his old rating has been put into the system … The one recent event he has played in should get re-rated tomorrow or Wednesday. …

It has been. Wow – re-born on the 4th of July.

Bill Smythe

[scottrparker]

@nolan

Rule 28E1 does not provide for using an unofficial rating lower than a player’s published rating. The exceptions in 28E2 are all justifications for using a higher rating than the player’s current published rating.

It is not clear to me that this is a rule that can be relaxed at all, much less without full advance publicity and an on-site announcement, including the possibility of a player being assigned a rating below that player’s current published rating.

This is another place where the rulebook could use updating to make it clear what the TD/organizer can and cannot do.

All you have to say in your publicity is “Rule 28E1 will not be in force”, or something of the sort. I assume that is what Micah Smith is doing for his quads. Since his players appear to like what he is doing I see no reason why he should not continue doing it.

Lots of places have “house rules” that don’t conform to anything in the rulebook. At the now defunct Atlanta Chess Center their policy was that if players in two different sections were due byes the TD would raise the lower section player up to the section of the higher section player and pair them with the game counting for tournament purposes for the higher section player only. Neither player had the right to take the bye and refuse to play the game.

The rulebook is lengthy enough already; we don’t need more rules intruding into spaces they don’t need to get into.

[relyea]

@scottrparker

The rulebook is lengthy enough already; we don’t need more rules intruding into spaces they don’t need to get into.

This is absolutely correct, but not for the reason Mr. Parker seems to think. The rulebook should be shortened 90%. Players should be able to expect consistency in the rules from Boston to LA, and from small clubs to the World Open. No one should ever go to a tournament without knowing what rules will be in force.

Alex Relyea

[scottrparker]

@relyea

@scottrparker

The rulebook is lengthy enough already; we don’t need more rules intruding into spaces they don’t need to get into.

This is absolutely correct, but not for the reason Mr. Parker seems to think. The rulebook should be shortened 90%. Players should be able to expect consistency in the rules from Boston to LA, and from small clubs to the World Open. No one should ever go to a tournament without knowing what rules will be in force.

Alex Relyea

I fully agree that no one should go to a tournament without knowing what rules will be in force, but the point here is that any significant variance from the standard rules must be announced in all pre-tournament publicity. CCA has it’s own set of rules for its tournaments. If you go to a CCA tournament you will only know what rules they will be using if you read their posted rules. If you don’t read them, that’s on you.

[Micah_Smith]

@scottrparker

All you have to say in your publicity is “Rule 28E1 will not be in force”, or something of the sort. I assume that is what Micah Smith is doing for his quads.

Correct.

@scottrparker

Since his players appear to like what he is doing I see no reason why he should not continue doing it.

Yes, the feedback from players on using the “live” ratings has been nothing but positive.

[nolan]

I ran a few tournaments using the McMahon Swiss pairing system, and had no issues with getting them rated by US Chess.

The US Chess ratings systems (and ratings systems in general, going all the way back to Elo’s original work on ratings) are pairing-indifferent, you can rate almost any type of event including 1 vs 2 pairings, ladders, and even pairings that are essentially random. All we need to know is who played whom and what the result was, not why they were paired.

The only limitations that US Chess has are for matches and for provisionally rated players, because those can violate one of the underlying mathematical assumptions behind the ratings system, which is that players will face a large pool of opponents; playing too many games against the same opponent can affect the reliability of those players’ ratings.

FIDE tends to be fussier about pairings, especially for events that can earn norms, but this is not a mathematics issue. I don’t know the complete history behind them, but I suspect the strictness of the FIDE rules on pairings were responses to attempts to manipulate events and norms.

[Micah_Smith]

@nolan

Rule 28E1 does not provide for using an unofficial rating lower than a player’s published rating. The exceptions in 28E2 are all justifications for using a higher rating than the player’s current published rating.

It is not clear to me that this is a rule that can be relaxed at all, much less without full advance publicity and an on-site announcement, including the possibility of a player being assigned a rating below that player’s current published rating.

This is another place where the rulebook could use updating to make it clear what the TD/organizer can and cannot do.

The deadline for an ADM was Monday, June 5

[nolan]

I’m not a current Delegate, though I am a former DAL, so I would be eligible for re-election to a 3 year term as a DAL if I attend a Delegates Meeting. But at this time I have no plans to do that, I’m retired and enjoying it.

[Micah_Smith]

@Smythe Dakota

The bottom section, however, was played as a 4-round Swiss with 6 players. (The TD, either by careful planning or through sheer luck, managed to avoid the infamous 6-player Swiss trap.)

What’s the best thing to do to make sure you avoid this trap?

[relyea]

@Micah Smith

@Smythe Dakota

The bottom section, however, was played as a 4-round Swiss with 6 players. (The TD, either by careful planning or through sheer luck, managed to avoid the infamous 6-player Swiss trap.)

What’s the best thing to do to make sure you avoid this trap?

Be very careful when you pair round 3 that you need not re-pair in round 4.

Alex Relyea

[Smythe_Dakota]

@Micah Smith

… What’s the best thing to do to make sure you avoid [ the 6-player Swiss ] trap?

The 6-player Swiss trap can rear its ugly head when 6 players are paired as a Swiss, and there are either 4 or 5 rounds.

Example (columns are player number, color history, round 1, round 2, round 3):

1 wbw W4 L2 W6
2 bwb W5 W1 W3
3 wbw W6 W4 L2
4 bwb L1 L3 W5
5 wbw L2 L6 L4
6 bwb L3 W5 L1

You will note that round 1 pairings are the normal top half vs bottom half. Round 2 are also the normal pairings, given the round 1 results, with winner vs winner, lowest-ranked winner vs highest-ranked loser, and loser vs loser. Round 3, also normal, pairs the 2-pointers against each other, the 1-pointers against each other, and the 0-pointers against each other.

Now try to pair round 4. You will find there are no pairings at all, even regardless of scores, ratings, or colors. Every pairing attempt involves matching somebody against an opponent he has already played.

How to avoid this trap? Some TDs prefer to use the Crenshaw-Berger tables for a 6-player round-robin, skipping one of the rounds if there are only 4 rounds. But this can get tricky, too.

I prefer to go ahead and pair it as a Swiss, BUT then you need to be careful when you pair round 3. (You can pair rounds 1 and 2 any way you want.)

When you (or the computer) spits out tentative round 3 pairings, just take a close look and see if there is any way at all to pair round 4. If so, go ahead. Round 5 will then work fine, because you would simply pair each player against the one player he has not yet met.

But if there are no round 4 pairings, make some transpositions in the round 3 pairings, and check again to see if there are round 4 pairings.

The following visual method may help a little. After round 2 is paired and the games are being played, draw a regular hexagon, with each vertex representing a player, and each side representing a pairing. In the pairings shown above, you would arrange the vertices in the order 1-4-3-6-5-2-1 going around (say) clockwise. This means, for example, that 4 has played both 1 and 3, etc around the circle, with 2 having also played 1, the hexagon having come full circle.

There are now four possible pairings for round 4:

(a) Pair each player against the player diametrically opposite across the hexagon.

(b) (c) (d) Pair ONE player against the player diametrically opposite across the hexagon, but pair the remaining four players each against an opponent NOT diametrically opposite.

Option (a) is the one that will get you into trouble. Options (b) (c) (d) will all work fine.

That means that you have a 25% chance of screwing up, if you don’t watch what you’re doing.

Bill Smythe

[scottrparker]

@Micah Smith

@Smythe Dakota

The bottom section, however, was played as a 4-round Swiss with 6 players. (The TD, either by careful planning or through sheer luck, managed to avoid the infamous 6-player Swiss trap.)

What’s the best thing to do to make sure you avoid this trap?

What you need to avoid in a four round tournament or section with six players is the situation where after round 3 you have two groups of three players each where each player has played every player in the other group, but no one in his own group. If you find that you have that there will be no way to pair round 4 without pairing two players who have already played.

It’s pretty simple to avoid this IF you plan ahead. After you make tentative pairings for round 3 just check to make sure you don’t have the two groups outlined above, or check to make sure you have a legal pairing for round 4. If you are about to run yourself into this trap just re-pair round 3 with the next best Swiss pairing. You will now have a legal pairing for round 4 (which you should confirm.)

[Smythe_Dakota]

@scottrparker

… What you need to avoid in a four round tournament or section with six players is the situation where after round 3 you have two groups of three players each where each player has played every player in the other group, but no one in his own group. If you find that you have that there will be no way to pair round 4 without pairing two players who have already played. …

Precisely. In my example, the two 3-player groups were those who started with white (players 1-3-5) and those who started with black (players 2-4-6):

1 wbw W4 L2 W6
2 bwb W5 W1 W3
3 wbw W6 W4 L2
4 bwb L1 L3 W5
5 wbw L2 L6 L4
6 bwb L3 W5 L1

In fact, perhaps the most likely way to fall into the 6-player trap is by making the colors work too well. If all the colors alternate in round 2, and all the colors alternate again in round 3 – as happened above – then you have automatically fallen into the trap.

It’s not just colors, though. For example, if you try to fix the above pairings by simply reversing the colors on one or two of the boards, that won’t help – you’ve still got the same two 3-player groups. When pairing round 3 with six players, always look for legal round 4 pairings, and if they don’t exist, change the round 3 pairings and check again for the existence of round 4 pairings.

… It’s pretty simple to avoid this IF you plan ahead. After you make tentative pairings for round 3 just check to make sure you don’t have the two groups outlined above, or check to make sure you have a legal pairing for round 4. If you are about to run yourself into this trap just re-pair round 3 with the next best Swiss pairing. You will now have a legal pairing for round 4 (which you should confirm.)

+1

Bill Smythe

[BIRDSNAN]

I was told by the rating dep
that for all new members they
search all available databases