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Login: | Explaining level changesDivision 3: Thornbury B v Workout Harbourside 4 (Wed 20 Mar 2024)Match played between Ben Winter (home) and Scott Purnell (away).Match won by Ben Winter. Result: 15-3,15-10,15-8. Starting level for Ben Winter: 1,095, level confidence: 80%. Set manually. Starting level for Scott Purnell: 729, level confidence: 66%. Ben Winter to win as he is currently playing 50% better than Scott Purnell. Ben Winter won all of the games and 68% 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 114% (PAR scoring). These are weighted and combined to calculate that Ben Winter played 114% better than Scott Purnell in this match. Assuming that any level changes are shared between both players, for this result it looks like Ben Winter actually played at a level of 1,308 and Scott Purnell at a level of 610. Without any damping, both players would need to be adjusted by 19% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 16% and 16% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Ben Winter changes to +13% and Scott Purnell changes to -16%. After applying standard match damping, the adjustment for Ben Winter becomes +7.5% and for Scott Purnell becomes -9.2%. Apply match/event weighting of 75% for 'Mixed Spring 2023/2024' so the adjustment for Ben Winter is +5.7% and for Scott Purnell is -6.7%. 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 Scott Purnell 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. Ben Winter: 89%, Scott Purnell: 81%. Reduce level confidence based on how unexpected the result is. Ben Winter: 75%, Scott Purnell: 68%. 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 Ben Winter: 1,155, level confidence: 75%. Final level for Scott Purnell: 693, level confidence: 68%. Notes
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