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Login: | Explaining level changesDivision 2: Whitchurch Imperial A v Thornbury C (Wed 31 Aug 2016)Match played between Lee Maynard/Richard Lay (home) and Bill Ellis/Nigel Ball (away).Match won by Bill Ellis/Nigel Ball. Result: 12-15,15-12,11-15,7-15. Starting level for Lee Maynard/Richard Lay: 964, level confidence: 28%. Starting level for Bill Ellis/Nigel Ball: 909, level confidence: 26%. Lee Maynard/Richard Lay to win as he is currently playing 6% better than Bill Ellis/Nigel Ball. Bill Ellis/Nigel Ball won 75% of the games and 56% of the points. This games result would be expected if he was better by around 25%. This points result would be expected if he was better by around 27% (PAR scoring). These are weighted and combined to calculate that Bill Ellis/Nigel Ball played 26% better than Lee Maynard/Richard Lay in this match. Assuming that any level changes are shared between both players, for this result it looks like Bill Ellis/Nigel Ball actually played at a level of 1,049 and Lee Maynard/Richard Lay at a level of 835. Without any damping, both players would need to be adjusted by 15% 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 Bill Ellis/Nigel Ball changes to +15% and Lee Maynard/Richard Lay changes to -14%. After applying standard match damping, the adjustment for Bill Ellis/Nigel Ball becomes +8.8% and for Lee Maynard/Richard Lay becomes -8.5%. Apply match/event weighting of 75% for 'Mixed Doubles 2016' so the adjustment for Bill Ellis/Nigel Ball is +6.6% and for Lee Maynard/Richard Lay is -6.2%. 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 Lee Maynard/Richard Lay 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. Bill Ellis/Nigel Ball: 51%, Lee Maynard/Richard Lay: 52%. Reduce level confidence based on how unexpected the result is. Bill Ellis/Nigel Ball: 45%, Lee Maynard/Richard Lay: 45%. Final level for Lee Maynard/Richard Lay: 918, level confidence: 45%. Final level for Bill Ellis/Nigel Ball: 969, level confidence: 45%. Notes
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