Arbitration question

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Kevin Thurlow
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Re: Arbitration question

Post by Kevin Thurlow » Sun Nov 01, 2020 9:33 am

"Anybody who wins a game by default goes to the bottom of the score group."

Again, that's a bit unfair as it's not usually your fault if you win on default. But I accept that tie-break systems all have faults.

At the Civil Service Championship, (as we had three trophies to distribute) we had at one stage:-

1) who beat whom
2) Sum Progressive Scores
3) Sum of Opponents' Scores
4) Sonneborn-Berger

trying to cover everything, then one year Neil Graham was arbiter and added "5) Pistols at dawn", which made everyone laugh. However, several years later, the players sharing second and third place were level on all 4 official tie-breaks. We didn't use 5)... Someone suggested, "5) player playing more games with black". We asked the two players what they thought and they happily agreed to that. One year we had a blitz play-off, but that has to be done straight after the last games finish. Someone who finished early might have relaxed, and the one who's just finished might be tired. So we gave that up.

So in answer to the original question, use whatever you like, just make sure you tell everyone in advance.

NickFaulks
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Re: Arbitration question

Post by NickFaulks » Sun Nov 01, 2020 9:48 am

Kevin Thurlow wrote:
Sun Nov 01, 2020 9:33 am
Someone who finished early might have relaxed
In North America, where playoffs are the norm, this has tended to mean spending their winnings getting completely blotto - or, in Bermuda's case, taking full advantage of the hospitality tent.
If you want a picture of the future, imagine a boot stamping on a human face — forever.

soheil_hooshdaran
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Re: Arbitration question

Post by soheil_hooshdaran » Wed Nov 04, 2020 1:24 pm

IM Jack Rudd wrote:
Sat Oct 31, 2020 4:20 pm
You'd have to be extraordinarily unlucky for TPR to not break a tie, so put that one somewhere in the list.
Sorry, how is TPR calculated?

Stewart Reuben
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Re: Arbitration question

Post by Stewart Reuben » Wed Nov 04, 2020 7:11 pm

TPR is quite laborious by hand, You consider each game played separately. Look at the rating of the opponent. If you draw, you get his rating. If you win, you et his rating + 400. If you lose his rating -400. Then add everything up.
Much simpler is to take the Rating average of your opponents. If one game didn't take place, then just forget about that game.

Disadvantage. If the opponent is more than +400 higher, or greater than -400 below, the result is distorted.

The main problem of splitting prizes is that, say there are 3 players involved in the tie and the total sum is 1000. Then each player gets 333.33. That can only be worked out by the treasurer after the games have finished.
There is another one. If players are eligible for more than one prize and also have the rule that no player can get more thn one prize. I have no intention of explaining the ramifications of that one.

soheil_hooshdaran
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Re: Arbitration question

Post by soheil_hooshdaran » Wed Nov 04, 2020 7:35 pm

So what should be the tie-break system?

soheil_hooshdaran
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Re: Arbitration question

Post by soheil_hooshdaran » Fri Nov 06, 2020 7:33 pm

This Friday, my Tie-break systems were
1-Direct encounter 2-Bucholz's 3-Average rating of opponents
https://lichess.org/swiss/Fuxemg9z
How do I calulate Average rating of opponents when a player had a bye the last round?

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IM Jack Rudd
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Re: Arbitration question

Post by IM Jack Rudd » Fri Nov 06, 2020 9:32 pm

The same way you always calculate it: add up the ratings of the players he played and divide by the number of games he played.

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