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NeilH
16-06-2007, 10:49 PM
I have been reading through the FIDE Swiss pairing rules trying to get a better understanding of them. However the closer I look at the rules the more questions I have. I hope someone here can help answer some of them.

I have been looking at the rules for Transpositions and Exchanges.
see: http://www.fide.com/official/handbook.asp?level=C0401D

I understand rule D.1 for transpositions, but I am struggling with the rule D.2 for exchanges.

The example shown implies there are 8 players in the score bracket, 4 players in S1 (1,2,3,4) 4 players in S2 (5,6,7,8). The exchanges shown seem to exclude players 1 and 8. I can't see anything in the rules for this.

So should player 1 and 8 be ignored for exchanges and if so why, or is the example wrong?

I hope someone can help

Neil

Denis_Jessop
17-06-2007, 12:33 PM
I have been reading through the FIDE Swiss pairing rules trying to get a better understanding of them. However the closer I look at the rules the more questions I have. I hope someone here can help answer some of them.

I have been looking at the rules for Transpositions and Exchanges.
see: http://www.fide.com/official/handbook.asp?level=C0401D

I understand rule D.1 for transpositions, but I am struggling with the rule D.2 for exchanges.

The example shown implies there are 8 players in the score bracket, 4 players in S1 (1,2,3,4) 4 players in S2 (5,6,7,8). The exchanges shown seem to exclude players 1 and 8. I can't see anything in the rules for this.

So should player 1 and 8 be ignored for exchanges and if so why, or is the example wrong?

I hope someone can help

Neil

Hi Neil

You would not be the first person to have trouble understanding tihs aspect (and a lot of others) of the FIDE Swiss rules. A friend of mine once said that they are really drafted as a basis for a computer program rather than to be understood by humans. I have never been an expert on the Transpositions and Exchanges rules though some others who contribute to this Board are better informed on them.

Another possibility, as I see you are from the UK, is to consult UK and FIDE expert Stewart Reuben who has written "The Chess Organiser's Handbook" dealing with all aspects of chess rules and organisation and whose e-mail address, given in the book, is Stewartreuben@aol.com.

DJ

Kevin Bonham
17-06-2007, 02:35 PM
I'm not sure whether the reason 1 and 8 are omitted is:

(a) it is very unlikely either 1 or 8 would ever need to be exchanged into the other group or

(b) it is intended to prohibit an exchange of 1 or 8 into the other group.

I'd expect it's the former because if it was the latter you'd think it would be more explicit. However if it is the former we need to keep in mind that an exchange of 4 and 8 is preferable over an exchange of 2 and 7 or even an exchange of 2 and 6.

Bill Gletsos
17-06-2007, 04:03 PM
I have been reading through the FIDE Swiss pairing rules trying to get a better understanding of them. However the closer I look at the rules the more questions I have. I hope someone here can help answer some of them.

I have been looking at the rules for Transpositions and Exchanges.
see: http://www.fide.com/official/handbook.asp?level=C0401D

I understand rule D.1 for transpositions, but I am struggling with the rule D.2 for exchanges.

The example shown implies there are 8 players in the score bracket, 4 players in S1 (1,2,3,4) 4 players in S2 (5,6,7,8). The exchanges shown seem to exclude players 1 and 8. I can't see anything in the rules for this.

So should player 1 and 8 be ignored for exchanges and if so why, or is the example wrong?

I hope someone can help

NeilThe example is correct and there is no need to exchange 1 or 8.

Bill Gletsos
17-06-2007, 04:20 PM
The reason why is that the situations of exchanging 1 or 8 are covered by all the exchanges already in the table.

Kevin Bonham
17-06-2007, 04:20 PM
Bill is correct. There is actually mathematically no need to ever exchange 1 out of S1 or 8 out of S2 because the same possibilities can always be covered without doing so.

eg suppose you exchange 8 out of S2 and into S1. Now 8 will be playing someone who is in S2, but that person has a lower number. So it would have been possible to leave that other person in S1 and leave 8 in S2 and that would have been a better solution.

NeilH
17-06-2007, 11:18 PM
Bill & Kevin. Thanks for this information it does make sense. I suppose this is also why you don't need to look at the exchange involving 3 players.

So my understanding is that when you have 8 players in a score bracket, you only have to look at exchanges involving 1 and 2 players and you don't need to exchange players 1 or 8.

If you have 10 players in the score bracket, again you can ignore the first and last player (eg 1 and 10). You need to look at exchanges involving 1 and 2 players and I think you also need to look at exchanges involving 3 players, but not 4 players. Is this correct?