12 votes
Accepted

How is Buchholz score calculated in a Swiss tournament?

The information is hidden away in Standards of Chess Equipment and tournament venue for FIDE Tournaments section 13.4. 13.4. Buchholz System 13.4.1. The Buchholz System is the sum of the scores ...
  • 81k
8 votes

Why can't FIDE use a Non-Deterministic Gender Neutral Swiss Pairing system?

The current algorithms are deterministic. I have no idea why you would want a non-deterministic algorithm. The advantage of the deterministic ones we currently use is that they can be easily done by ...
  • 26.4k
8 votes

Is there a tournament system that pairs players based on ratings being similar?

Swiss tournaments somewhat attempt to do what you want in their later rounds. Also, tournament organizers often have different ratings-based sections for larger Swiss events to reduce the number of ...
  • 2,434
7 votes

Looking for online Swiss pairing software

You could try this free service: https://swisssystem.org/ It’s simple and easy to use. It works fine on mobile devices. The maximum player count is 200.
7 votes
Accepted

Which pairing programs have been authorized by FIDE for use in FIDE rated tournaments?

FIDE publish a list of such programs here. Currently there are 10 programs on the list varying in price from completely free (Tornelo, STOP), free on Linux (Vega), partially free (ChessManager) to 150 ...
  • 81k
6 votes

How can I know if the chief arbiter has "cheated" in the pairings and possibly report it?

I participated in a local, FIDE-rated tournament. In its first round, the chief arbiter paired the players 4 times This has happened to me too, although not as many as 3 repairings that I am aware. ...
  • 81k
6 votes
Accepted

Swiss-pairing algorithm

is there any good and free software available for setting up swiss tournaments? All of those I've tried have very few options and little functionality available. Vega is a swiss pairing program ...
  • 81k
5 votes

Looking for online Swiss pairing software

SWIPS is also online tool for managing tournaments. It includes much more than just a swiss system and round robin, but you can use it solely for that purpose if you want. Right now its free, ...
5 votes

Is there a tournament system that pairs players based on ratings being similar?

I want to give an unequivocal "No" as the answer, but that's too simple. General Swiss pairing rules (for where you want to find a winner from lots of players / teams and few rounds / ...
  • 81k
4 votes

Swiss-pairing algorithm

As for tournaments with swiss system, many computer programs are paid. That's why I decided to create a freeware program (REALLY free). Name of my program is VinczeSwiss. The VinczeSwiss program is ...
  • 49
4 votes

Looking for online Swiss pairing software

An offline alternative is Vegachess, which it is also homologated by FIDE. AFAIK Vegachess just uses javafo as its pairing engine. Linux version of vegachess is free to use and Windows version not ...
  • 1,161
4 votes
Accepted

In what way is it allowed to alter tournament pairings in favor of a player?

It says the exact opposite. C.04.2 A It is not allowed to alter the correct pairings in favour of any player. So no, you can't. Where it can be shown that modifications of the original ...
  • 26.4k
4 votes
Accepted

How do I determine the bye player in a Swiss tournament?

In the first round, it should go to the player with the lowest initial ranking. After that, it depends, but it would ordinarily go to a low ranked player in the lowest score group. According to rule ...
  • 15.8k
4 votes
Accepted

Record Swiss top tie

There are a couple of records of this sort in the relevant Wikipedia page. To quote: Thirteen players tied for first with 5–1 scores at the National Open held on March 17–19, 2000 in Las Vegas: ...
  • 22.6k
3 votes

A Swiss nightmare

Assume a 9 round Swiss tournament with 2^9 players, White always wins. Will the pairing computer (definitely not super quantum) go berserk? Thank you for clarifying the difference between NA (...
  • 81k
3 votes
Accepted

Predicting color and opponent

One sure-fire way is for you to buy your own copy of Swiss Manager, the pairing software used in this particular case, and reproduce the tournament and then do the next round pairing once all the ...
  • 81k
3 votes

Swiss system pairing algorithm stuck

Is this situation logically possible? Certainly. This is one of the known problems with using Swiss pairing when the number of rounds is close to the number of players. It is called "jamming". ...
  • 81k
3 votes
Accepted

Looking for online Swiss pairing software

My club uses Swiss Manager. It is very good but not cheap. 150 euros for the full version, 75 euros for the light. It is perhaps worth looking at what it does to get ideas if you are thinking of ...
  • 81k
3 votes

Why can't FIDE use a Non-Deterministic Gender Neutral Swiss Pairing system?

Surely we can create opt out for gender pairings which occur consecutively? Yes, we could. We can make whatever rules we like, after all. But I don't think we should. Such a rule would have to ...
  • 15.8k
3 votes
Accepted

Multiple teams from the same country in Swiss system

There is a tradeoff between making the pairings that "should" be made according to the strict pairing rules, and attempting to prevent collusion. Imagine this scenario: Russia 1: 8.5 Russia 2: 8 ...
  • 15.8k
3 votes

Looking for online Swiss pairing software

If you are looking for an easy-to-use, FIDE-approved online platform, take a look at ChessManager.
3 votes
Accepted

How can I use JaVaFo in my pairing program?

According to the website for the engine it was written by international arbiter Roberto Ricco: The author JaVaFo is authored and intellectually owned by Roberto Ricca, former programmer, ...
  • 81k
3 votes
Accepted

Pairing Preference in Swiss Tournament System

There are various Swiss pairing systems. On the assumption that because you are asking in a chess forum you are asking about the most commonly used Swiss pairing systems in the chess world. After your ...
  • 81k
3 votes

What is a good approach to conduct a round robin event for 20 players in order to select top 6?

To get the fairness of a round-robin without quite so many games... First, separate your players into 2 groups of 10. I'd suggest making the groups each have a good mix of players rather than having a ...
  • 15.8k
2 votes

Swiss system chess tournament

Swiss system has nothing to do with time controls. It is a tournament pairing system based on the principle that in each round players with so far similar results are paired together, and that each ...
  • 364
2 votes

Intervening with swiss pairing

Is there an option in the pairing program to set this? Of course. Different approved Swiss pairing programs will do this is different ways. You should check out the User Manuals for the different ...
  • 81k
2 votes
Accepted

How does the JaVaFo engine work and how random are the pairings?

What are those rules? The rules are defined in the FIDE document C.04.1 Basic rules for Swiss Systems. C.04.1 Basic rules for Swiss Systems The following rules are valid for each Swiss system unless ...
  • 81k
2 votes

How do I determine the bye player in a Swiss tournament?

Note:   Independently from the route followed, the assignment of the pairing-allocated bye (see C.2) is part of the pairing of the last bracket. https://www.fide.com/component/handbook/?id=170&...
  • 10.3k
2 votes

Swiss-pairing algorithm

You can use Schachturnierorganisationsprogramm for Swiss-Tournaments. Since FIDE-Congress Abu Dhabi 2020 Schachturnierorganisationsprogramm is endorsed by the SPP-Commission. My program is open-source ...
2 votes

Is there a tournament system that pairs players based on ratings being similar?

I believe you are looking for the Monrad system. This is a variant of the Swiss system in which, in each round, players are grouped by score and then listed in order of descending rating (or seeding),...
  • 3,469

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