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Login: | Explaining level changesDivision 1: Workout Harbourside A v Lansdown A (Thu 14 Nov 2019)Match played between Emma Coughlan (home) and Pippa Green (away).Match won by Emma Coughlan. Result: 15-4,15-10,15-12:15-10,15-7,13-15,15-17,15-11:15-6,16-14,15-9:15-7,15-2,15-4. Starting level for Emma Coughlan: 1,718, level confidence: 62%. Starting level for Pippa Green: 1,621, level confidence: 77%. Set manually. Emma Coughlan to win as she is currently playing 6% better than Pippa Green. Emma Coughlan won all of the games and 63% of the points. This games result would be expected if she was better by around 55% or more. This points result would be expected if she was better by around 73% (PAR scoring). These are weighted and combined to calculate that Emma Coughlan played 73% better than Pippa Green in this match. Assuming that any level changes are shared between both players, for this result it looks like Emma Coughlan actually played at a level of 2,195 and Pippa Green at a level of 1,268. Without any damping, both players would need to be adjusted by 28% 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 Emma Coughlan changes to +27% and Pippa Green changes to -20%. After applying standard match damping, the adjustment for Emma Coughlan becomes +11.4% and for Pippa Green becomes -9.3%. Apply match/event weighting of 75% for 'Womens Ladies Autumn 2019/2020' so the adjustment for Emma Coughlan is +8.6% and for Pippa Green is -6.9%. 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 Pippa Green 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. Emma Coughlan: 79%, Pippa Green: 88%. Reduce level confidence based on how unexpected the result is. Emma Coughlan: 62%, Pippa Green: 69%. 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 Emma Coughlan: 1,843, level confidence: 62%. Final level for Pippa Green: 1,571, level confidence: 69%. Notes
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