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Login: | Explaining level changesPremier A: Lansdown 1 v Thornbury A (Wed 31 Jan 2018)Match played between Andy Killey (home) and Craig Webb (away).Match won by Craig Webb. Result: 3-11,5-11,6-11. Starting level for Andy Killey: 5,081, level confidence: 62%. Starting level for Craig Webb: 5,334, level confidence: 77%. Set manually. Craig Webb to win as he is currently playing 5% better than Andy Killey. Craig Webb won all of the games and 70% 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 136% (PAR scoring). These are weighted and combined to calculate that Craig Webb played 136% better than Andy Killey in this match. Assuming that any level changes are shared between both players, for this result it looks like Craig Webb actually played at a level of 7,993 and Andy Killey at a level of 3,391. Without any damping, both players would need to be adjusted by 50% 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 Webb changes to +39% and Andy Killey changes to -48%. After applying standard match damping, the adjustment for Craig Webb becomes +11% and for Andy Killey becomes -13%. Given Craig Webb's level and the type of match played, an additional damping of 1.4% has been applied to his level change. Given Andy Killey's level and the type of match played, an additional damping of 0.4% has been applied to his level change. Looks like he wasn't taking the match too seriously... Apply match/event weighting of 75% for 'Mixed Spring 2017/2018' so the adjustment for Craig Webb is +8.1% and for Andy Killey is -9.6%. 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 Andy Killey 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 Webb: 88%, Andy Killey: 79%. Reduce level confidence based on how unexpected the result is. Craig Webb: 58%, Andy Killey: 52%. A final adjustment of -0.3% 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 Andy Killey: 4,905, level confidence: 52%. Final level for Craig Webb: 5,659, level confidence: 58%. Notes
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