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Login: | Explaining level changesPremier C: Westbury David Lloyd A v Shepton Mallet A (Wed 03 Dec 2014)Match played between Kirk Woodward (home) and David Cox (away).Match won by David Cox. Result: 2-9,2-9,6-9. Starting level for Kirk Woodward: 2,236, level confidence: 78%. Set manually. Starting level for David Cox: 2,326, level confidence: 67%. David Cox to win as he is currently playing 4% better than Kirk Woodward. David Cox won all of the games and 73% 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 67% (english scoring). These are weighted and combined to calculate that David Cox played 67% better than Kirk Woodward in this match. Assuming that any level changes are shared between both players, for this result it looks like David Cox actually played at a level of 2,947 and Kirk Woodward at a level of 1,765. Without any damping, both players would need to be adjusted by 27% 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 David Cox changes to +26% and Kirk Woodward changes to -22%. After applying standard match damping, the adjustment for David Cox becomes +10% and for Kirk Woodward becomes -8.8%. Apply match/event weighting of 75% for 'Mixed Autumn 2014/2015' so the adjustment for David Cox is +7.5% and for Kirk Woodward is -6.4%. 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 Kirk Woodward 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. David Cox: 82%, Kirk Woodward: 88%. Reduce level confidence based on how unexpected the result is. David Cox: 65%, Kirk Woodward: 70%. A final adjustment of -0% 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 Kirk Woodward: 2,126, level confidence: 70%. Final level for David Cox: 2,504, level confidence: 65%. Notes
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