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Login: | Explaining level changesDivision 2: Kingsdown v University of Bath Ladies A (Tue 09 May 2023)Match played between Sandra Newth (home) and Thea Uttley (away).Match won by Thea Uttley. Result: 4-15,4-15,5-15. Starting level for Sandra Newth: 191, level confidence: 54%. Starting level for Thea Uttley: 459, level confidence: 73%. Set manually. Thea Uttley to win as she is currently playing 140% better than Sandra Newth. Thea Uttley won all of the games and 78% 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 246% (PAR scoring). These are weighted and combined to calculate that Thea Uttley played 246% better than Sandra Newth in this match. Assuming that any level changes are shared between both players, for this result it looks like Thea Uttley actually played at a level of 551 and Sandra Newth at a level of 159. Without any damping, both players would need to be adjusted by 20% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 11% and 12% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Thea Uttley changes to +8.4% and Sandra Newth changes to -12%. After applying standard match damping, the adjustment for Thea Uttley becomes +5.7% and for Sandra Newth becomes -7.7%. Apply match/event weighting of 75% for 'Womens Womans Spring 2022/2023' so the adjustment for Thea Uttley is +4.3% and for Sandra Newth is -5.7%. 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 Sandra Newth 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. Thea Uttley: 85%, Sandra Newth: 74%. Reduce level confidence based on how unexpected the result is. Thea Uttley: 71%, Sandra Newth: 61%. 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 Sandra Newth: 182, level confidence: 61%. Final level for Thea Uttley: 478, level confidence: 71%. Notes
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