User blog comment:Bachoru/Leavers, ELO and more/@comment-569195-20110509205406

ELO is a broad concept. ELO as it was originally created is not used any more, the concepts are the same but there have been a lot of better models proposed and used in various places. I expect that Riot uses a more complicated form of ELO than that discussed here on the wiki. Since we don't know the actual formulas riot uses I only put the most basic information into that article. The ELO equations used for chess do not work well in team games but there are versions of ELO where designed for team sports.