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Login: | Explaining level changesDivision 1: Lansdown A v Workout Harbourside A (Thu 19 Oct 2023)Match played between Quita Colston (home) and Kathryn Field (away).Match won by Kathryn Field. Result: 7-15,6-15,5-15. Starting level for Quita Colston: 576, level confidence: 40%. Starting level for Kathryn Field: 646, level confidence: 75%. Set manually. Kathryn Field to win as she is currently playing 12% better than Quita Colston. Kathryn Field won all of the games and 71% 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 150% (PAR scoring). These are weighted and combined to calculate that Kathryn Field played 150% better than Quita Colston in this match. Assuming that any level changes are shared between both players, for this result it looks like Kathryn Field actually played at a level of 964 and Quita Colston at a level of 386. Without any damping, both players would need to be adjusted by 49% 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 Kathryn Field changes to +25% and Quita Colston changes to -46%. After applying standard match damping, the adjustment for Kathryn Field becomes +13.3% and for Quita Colston becomes -23%. Apply match/event weighting of 75% for 'Womens Autumn 2023/2024' so the adjustment for Kathryn Field is +10% and for Quita Colston is -16%. 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 Quita Colston 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. Kathryn Field: 87%, Quita Colston: 63%. Reduce level confidence based on how unexpected the result is. Kathryn Field: 58%, Quita Colston: 43%. A final adjustment of -0.2% 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 Quita Colston: 548, level confidence: 43%. Final level for Kathryn Field: 709, level confidence: 58%. Notes
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