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Login: | Explaining level changesFrank Major v Todd Bennett (Sat 10 Nov 2012)Match won by Todd Bennett. Result: 7-11,1-11,3-11.Starting level for Frank Major: 1,738, level confidence: 23%. Starting level for Todd Bennett: 2,708, level confidence: 39%. Todd Bennett to win as he is currently playing 56% better than Frank Major. Todd Bennett won all of the games and 75% 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 200% (PAR scoring). These are weighted and combined to calculate that Todd Bennett played 200% better than Frank Major in this match. Assuming that any level changes are shared between both players, for this result it looks like Todd Bennett actually played at a level of 3,758 and Frank Major at a level of 1,253. Without any damping, both players would need to be adjusted by 39% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 30% and 30% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Todd Bennett changes to +17% and Frank Major changes to -30%. After applying standard match damping, the adjustment for Todd Bennett becomes +6.9% and for Frank Major becomes -13%. Apply match/event weighting of 100% for 'Avon Junior Closed' so the adjustment is unchanged. 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 Frank Major 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. Todd Bennett: 63%, Frank Major: 48%. Reduce level confidence based on how unexpected the result is. Todd Bennett: 45%, Frank Major: 34%. 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 Frank Major: 1,659, level confidence: 34%. Final level for Todd Bennett: 2,902, level confidence: 45%. Notes
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