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Login: | Explaining level changesDivision 1B: Thornbury C v Redland Z (Wed 03 Dec 2014)Match played between Ian Talbot (home) and Paul Gaffney (away).Match won by Ian Talbot. Result: 9-2,9-7,9-0. Starting level for Ian Talbot: 1,193, level confidence: 83%. Set manually. Starting level for Paul Gaffney: 1,341, level confidence: 27%. Paul Gaffney to win as he is currently playing 12% better than Ian Talbot. Ian Talbot won all of the games and 75% 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 76% (english scoring). These are weighted and combined to calculate that Ian Talbot played 76% better than Paul Gaffney in this match. Assuming that any level changes are shared between both players, for this result it looks like Ian Talbot actually played at a level of 1,678 and Paul Gaffney at a level of 953. Without any damping, both players would need to be adjusted by 41% to match this result. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Ian Talbot changes to +12% and Paul Gaffney changes to -38%. After applying standard match damping, the adjustment for Ian Talbot becomes +7% and for Paul Gaffney becomes -17%. Apply match/event weighting of 75% for 'Mixed Autumn 2014/2015' so the adjustment for Ian Talbot is +5.2% and for Paul Gaffney is -12%. 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 Talbot: 91%, Paul Gaffney: 52%. Reduce level confidence based on how unexpected the result is. Ian Talbot: 65%, Paul Gaffney: 37%. A final adjustment of -0.4% 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 Talbot: 1,254, level confidence: 65%. Final level for Paul Gaffney: 1,270, level confidence: 37%. Notes
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