Swiss Pairing Question

Running Chess Tournaments
1

I am trying to educate someone on the correct way to pair Round 1 and I need help.

Let’s suppose there are 7 players registered in a tourney.

Following normal swiss pairing rules, he players would first be sorted from highest rating to lowest rating. The lowest rated player (seed 7) would get the bye. Then two sub groups are made, S1 for the high seeds and S2 for the low seeds. Thus the pairings for Round 1 would be:

1 vs 4
2 vs 5
3 vs 6
7 vs Bye

Now my problem is that the person that I am trying to educate on the correct way to pair Round 1 wants to do the following.

Sort players from highest seed to lowest seed and then pair the players as if there were 8 players registered which generates the following pairings for 7 players:

1 vs 5
2 vs 6
3 vs 7
4 vs Bye

Please note that IF there were 8 players registered for this tournament that the Bye would be replaced by Player 8.

The person wants to use the above pairings as he sees this as more logical and fair to players. The logic is that his pairings are identical to the pairings for 8 players with player 8 being replaced by Bye (which is done in Round Robin). He believes that the same pairings should be used for odd numbers, which makes the middle rated player have the Bye instead of the lowest rated player.

My question is whether this is a big deal that seriously contradicts the principles of Swiss or is this something that would be acceptable under Swiss guidelines. I know this is not how pairings are to be done under the USCF Rule Book so my question really is that if someone is not doing a USCF rated tournament, would the way this person wants to do pairings violate or contradict the correct way to generate Swiss System pairings. I would like some feedback on this and any suggestions on how I can convince this person that the USCF Swiss System pairings are fairer than the pairings procedure he wants to follow. He is telling me that his system is more logical and fairer.

If pairing his way is not a big deal, please let me know as I have been going head to head on this and cannot seem to get him to see the reason for doing it the way I was trained.

Can anyone help?

2

It’s important to give the bye to the correct person (in this case number 7) because that is the person LEAST likely to be in contention for the first place prize. You don’t want a person to win the tournament thanks to a 1 point bye.

3

[size=109]Yes, you can do this in a swiss system tournament. You would just need to announce the variation in your pretournament publicity for a rated event.

I fail to see how this is more logical. If there were an eighth player, he wouldn’t necessarily have to be the lowest rated player. Chances are that player 4 would not be paired against him. [/size]

4

If there are only 8 players entered in a tournament, then seed 4 would play seed 8, the lowest rated player.

I prefer to follow the pairing procedures approved by USCF but this person is telling me that pairing players his was is more logical and fairer.

I am trying to determine if there is a major problem doing the pairings as he is suggesting and, if this is a problem, how can I exaplain to him that his way is not more logicial and fairer.

5

If there was an 8th entry, wouldn’t you assume that he was an average entry and not the lowest rated. So, consider him to be the average - i.e. ranked 4th:

1st - 5th (really the old 4th)
2nd - 6th (really the old 5th)
3rd - 7th (really the old 6th)
4th (BYE) - 8th (really the old 7th)

and you get the traditional pairing.

6

Giving the bye to player 4 is illogical for several reasons, some of which have already been pointed out.

  1. The analogy to a round robin fails - everyone will play everyone eventually so you aren’t awarding a full point bye, you’re merely deciding in what sequence the players get their round off.

  2. As pointed out, you want to give the bye to the player least likely to win the tournament. Besides, who knows, you may get a late entrant.

  3. While it is true that if there were 8 players 4 would play 8, we have no way to know what pairing position this phanom player would occupy. To assert that original player 4 would be the one to play this hypothetical entrant is fallacious.

  4. There is no compelling reason to vary from the rules. This person is basically saying “I don’t like the rules, I like my way”. I’d hate to play in an event run by such a person. I certainly wouldn’t trust them to make correct rulings in any of the more controversial situations that may arise.

This reminds me of the old days when there was controversy over whether to drop the middle player or the lowest rated player in a scoregroup with an odd number of players. Eventually, dropping the low person became standard.

7

The Harkness is still used by some, and is, I believe, a variation in the rulebook.

Anyway, to Deanna: There will always be those who “have a better ‘more logical’ way of running your tournament”. The majority of these people have not even heard of the rulebook, much less read it.

Do it the way you know is legal, Deanna.

However, as Grant said, you could pair this way if you posted it in pre-publicity. You could even force all players to stand on their head before each round, if you published that requirement in pre-publicity ads :laughing:

8

One of my favorite tournaments when I was starting out was paired differently for each of the early rounds. The players might be ‘ranked’ tallest to shortest in the first round, with the next round oldest to youngest within their score group. As I recall this was done for the first couple of rounds and then paired normally for the remaining rounds.

9

You and your friend are arguing two different points, which means that arguing with him is pointless. You’re saying one system is standard, he’s saying the other system is more logical. Let it go.

His way does have a certain logic to it. The bye is being awarded to the lowest player who has a reasonable expectation of winning in the first round.

When the lowest-rated gets the bye, often he is paired against tough (for him) competition in every round thereafter, and never gets to play anybody close to his own strength.

But, I agree with you – stick to the rulebook.

Better yet, find some way to avoid the bye altogether – cross-round pairings, house players, etc. For example, you could jump in yourself and play in any round where there would otherwise be an odd number.

Bill Smythe

10

Let’s say it’s round 4 of a swiss and you have eight players tied at 1.5. On first pass, the pairings look like this:

Board 1: Albert (2000) - Edward (1610)
Board 2: Brad (1950) - Frank (1605)
Board 3: Chris (1700) - Greg (1400)
Board 4: Doug (1690) - Howard (1300)

Albert and Edward haven’t played, so you leave it alone for now.
But Brad and Frank have played before. Do you:
(A) transpose Frank and Greg because it’s important to preserve board 1 as it fell naturally?
OR
(B) transpose Edward and Frank because it’s important to minimize ratings impacts in transpositions?

The 5th Edition seems to gloss over the transpositions necessary to avoid players meeting twice in a swiss. There’s a lot more guidance on colors.

If you chose (A) above, what if Brad had also played Greg? Do you:
(A) do the three way transposition with Howard coming up to play Brad followed by Chris-Edward and Doug-Frank?
OR
(B) or just switch Edward and Frank?

11

Assuming colors work out, just swap Edward and Frank.

For that matter, even if colors don’t work out as well, you may be better off with that swap. The other transpositions are rather large.

Of course you also have a couple of possible interchanges. Without knowing ALL the information, it’s impossible to say which would be best.

There is NO preference AFAIK in the rules for preserving “board 1” pairings vs. “board 3”, and all of the players in your example are from the middle score group anyway (so they really wouldn’t be on board “1”). There definately is a good reason to minimize the size of any transpositions or interchanges.

12

“B” is correct.

Probably because there is no limit to the rating difference for transpositions to avoid pairing players twice. However, you should still follow the principle of “minimize rating difference” when deciding on a transpostion.

13

B, definitely. It’s not important WHERE the transposition occurs. Just minimize the rating differences involved in the transpositions. This is true regardless of the reason for the transpositions – colors, avoiding repeat pairings, or whatever.

If Edward and Frank had had a larger rating difference than Frank and Greg, so that A would be the preferred transposition, but then you notice that Brad had already played Greg, you’d just go back to the “raw” pairings (above), then make transposition B. This is way simpler, and probably involves smaller rating differences, than a three-way transposition.

Bill Smythe

14

A couple follow-up questions to my hijacked thread:

If both transpositions had been “small” (? less than 80 points), but the upper transposition is smaller by 1 point, would the upper transposition still be “better”? If the transpositions were exactly equal, is the lower transposition then preferred?

15
  1. Yes. Of course, this a purely arbitrary rule (since a 1-point difference is meaningless), but many of the pairing rules involve arbitrary choices. 2) I don’t think so. Can anyone cite a rule to the contrary? As a practical matter, if I were making pairings by hand, I would work from the top down and almost certainly make the first transposition.
16

As far as I can tell, the rules provide no “tie-breaker” for the case where two transpositions are exactly equal. So I suppose you could use anything you’re comfortable with, such as your preserving-board-one idea. Or, you could minimize the rating differences on the “other” side, i.e. the opponents’ rating difference.

By “first” I assume you mean (A), since that was mentioned first in the original question. In this case that would be the “lower” transposition.

Bill Smythe

17

No, I meant that, when using pairing cards, I would pair from the top down. So, if there were equivalent transpositions between boards 1 - 2, and boards 3 - 4, I would make the first one and move on.

18

Hmm, I guess “top down” means different things to different people.

In this case, I would have thought “top down” would mean that, since the first pairing is OK, you’d leave it, then when you see the second pairing needs changing, you’d transpose it with the third.

Bill Smythe

19

The issue of “top down” is most interesting.

Let me give a few examples here is a much more simplified way, assume no need for transpositions based on color):

Example 1:

This is Round 2 of a tournament:

Pairings are (listed in order by ID, rating, win.loss):

A 4213 (1) v B 2065 (1)
C 1892 (1) v D 2855 (0)
E 3171 (0) v F 2739 (0)

C and D played before in Round 1.

Do we transpose Players B and C (rating differnce of 173) or do we transpose Players D and E (rating differnce of 316)? Transposing B and C results in the smallest rating difference but there is nothing wrong with the pairings for the first board.

My vote is to leave Players A and B as is and transpose Players D and E.

Example 2 (which is really the same as Example 1 with great differences in ratings):

This is Round 2 of a tournament:

Pairings are (listed in order by ID, rating, win.loss):

A 3147 (1) v B 2329 (1)
C 1949 (1) v D 2913 (0)
E 4055 (0) v F 2088 (0)

C and D played before in Round 1.

Do we transpose Players B and C (rating differnce of 380) or do we transpose Players D and E (rating differnce of 1142)? Transposing B and C results in the smallest rating difference but there is nothing wrong with the pairings for the first board.

My vote is to leave Players A and B as is and transpose Players D and E.

Please note that the ratings provided are not USCF ratings; I am using the actual ratings of players provided by Leaga.

This sort of thing happens alot in 6 Player tourneys; I believe it is always best to leave board 1 as is, except if the players on Board 1 have already played before, in which case, if A and B played before, we would transpose Players B and C, so that Player A is still playing someone with the same win/loss record.

Any thoughts, comments, etc.?

DMDesiderata
Leagues Support Director
Swiss Training Director
Leaga.com

20

I forgot to include the third example. Again assume no need for transpositions based on color.

Example 3:

This is round 3 of the tournament.

Pairings are (ID, rating, win/loss):

A 3322 (1) vs B 2956 (1)
C 1997 (1) vs D 1981 (0)
E 1000 (0) vs F 2701 (0)

The first two boards include duplicate pairings. Player A played Player B in Round 1 and Player C Played Player D in Round 2.

Player C was floated upward in Round 2 and Player D was floated downward in Round 2.

A has already played E in Round 1.

Is it best to transpose Player B and D so that C is not floated upward a second time?

Suggestions?

DMDesiderata
Leagues Support Director
Swiss Training Director
Leaga.com