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Login: | Explaining level changesDivision 3: Weston Shankers v Thornbury B (Wed 17 Nov 2021)Match played between Craig Skinner (home) and Cliff Hall (away).Match won by Craig Skinner. Result: 15-11,15-5,14-16,15-11:14-16,17-15,9-15,15-13,12-15:12-15,15-12,15-9,12-15,15-11:6-15,15-12,12-15,15-6,6-15:16-14,9-15,5-15,5-15. Starting level for Craig Skinner: 1,615, level confidence: 82%. Set manually. Starting level for Cliff Hall: 1,965, level confidence: 70%. Cliff Hall to win as he is currently playing 22% better than Craig Skinner. Craig Skinner won 75% of the games and 58% 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 37% (PAR scoring). These are weighted and combined to calculate that Craig Skinner played 29% better than Cliff Hall in this match. Assuming that any level changes are shared between both players, for this result it looks like Craig Skinner actually played at a level of 2,024 and Cliff Hall at a level of 1,568. Without any damping, both players would need to be adjusted by 25% 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 Craig Skinner changes to +19% and Cliff Hall changes to -23%. After applying standard match damping, the adjustment for Craig Skinner becomes +8.9% and for Cliff Hall becomes -9.5%. Apply match/event weighting of 75% for 'Mixed Autumn 2021/2022' so the adjustment for Craig Skinner is +6.7% and for Cliff Hall is -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 Cliff Hall 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. Craig Skinner: 90%, Cliff Hall: 83%. Reduce level confidence based on how unexpected the result is. Craig Skinner: 72%, Cliff Hall: 67%. A final adjustment of -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 Craig Skinner: 1,691, level confidence: 72%. Final level for Cliff Hall: 1,869, level confidence: 67%. Notes
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