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Login: | Explaining level changesIan Beavon v Paul Gaffney (Sat 30 Oct 2021)Match won by Ian Beavon. Result: 9-1,9-0,9-0.Starting level for Ian Beavon: 1,440, level confidence: 82%. Set manually. Starting level for Paul Gaffney: 964, level confidence: 68%. Ian Beavon to win as he is currently playing 49% better than Paul Gaffney. Ian Beavon won all of the games and 96% of the points. This games result would be expected if he was better by around 55% or more. This points result would be expected if he was better by around 379% (english scoring). These are weighted and combined to calculate that Ian Beavon played 379% better than Paul Gaffney in this match. Assuming that any level changes are shared between both players, for this result it looks like Ian Beavon actually played at a level of 2,579 and Paul Gaffney at a level of 538. Without any damping, both players would need to be adjusted by 79% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 61% and 61% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Ian Beavon changes to +50% and Paul Gaffney changes to -61%. After applying standard match damping, the adjustment for Ian Beavon becomes +20.8% and for Paul Gaffney becomes -29%. Apply match/event weighting of 50% for 'Redland Green Boxes' so the adjustment for Ian Beavon is +10.4% and for Paul Gaffney is -13%. Apply limits to the amount of change for a single match which are based on player level, level confidence and time since last match so that Paul Gaffney is limited to -5% level change. In general a player's level won't go up by more than 10% or drop more than 5% if they've played in the last 7 days but those limits are relaxed if their previous match was further back. Increase level confidence due to one more match played. Ian Beavon: 91%, Paul Gaffney: 82%. Reduce level confidence based on how unexpected the result is. Ian Beavon: 51%, Paul Gaffney: 46%. A final adjustment of -0.1% has been made to both players as part of the automatic calibration that is performed after each match. All players in this pool will have been adjusted equally in order to remain equivalent to other player pools. Final level for Ian Beavon: 1,582, level confidence: 51%. Final level for Paul Gaffney: 917, level confidence: 46%. Notes
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