Wikipedia:Reference desk/Archives/Entertainment/2022 November 10

= November 10 =

Chess ELO based on games or matches?
Is the Chess ELO rating system based on games or matches? So when Masters play a series of games against each other, does the result of each game impact their ELO, or just the result of the complete match (essentially treating the entire series as a single game)? The Jade Knight (talk) 21:27, 10 November 2022 (UTC)


 * Assuming this is about the current FIDE ratings system (see ), the FIDE Rating Regulations effective from 1 January 2022 apply. Section 1.0 states that a played game will be rated when it took place in a FIDE registered tournament and meets certain requirements. Sections 1 through 5 appear to be about requirements for tournaments or games played in tournaments. Then, Section 6 is about matches, which appear to be a different species than tournaments. Although Section 6.1 states, "Matches in which one player is unrated shall not be rated", the next section implies that it is the games of the match that are rated (or not). So the answer appears to be that the input to the rating calculations is formed by the outcomes of the games. --Lambiam 04:02, 11 November 2022 (UTC)
 * However live ratings that change every game instead of every month are still unofficial last time I checked. Chess matches are a very different thing from tournaments. Matches are when two players play a predefined schedule of games, tournaments are where a bunch of players play a round-robin (probably always a double round-robin for fairness) or a Swiss tournament or sometimes it's another tournament format. Sagittarian Milky Way (talk) 03:12, 13 November 2022 (UTC)