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Login: | Explaining level changesDivision 2A: University of Bath 2 v Redwood Phoenix (Thu 10 Oct 2013)Match played between Alastair Cox (home) and Ivan Fisher (away).Match won by Alastair Cox. Result: 9-0,9-2,9-0. Starting level for Alastair Cox: 876, level confidence: 27%. Starting level for Ivan Fisher: 454, level confidence: 59%. Alastair Cox to win as he is currently playing 93% better than Ivan Fisher. Alastair Cox won all of the games and 93% 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 278% (english scoring). These are weighted and combined to calculate that Alastair Cox played 278% better than Ivan Fisher in this match. Assuming that any level changes are shared between both players, for this result it looks like Alastair Cox actually played at a level of 1,226 and Ivan Fisher at a level of 324. Without any damping, both players would need to be adjusted by 40% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 27% and 27% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Alastair Cox changes to +27% and Ivan Fisher changes to -11%. After applying standard match damping, the adjustment for Alastair Cox becomes +14.5% and for Ivan Fisher becomes -7%. Apply match/event weighting of 75% for 'Mixed Autumn 2013/2014' so the adjustment for Alastair Cox is +10.9% and for Ivan Fisher is -5.1%. 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 Alastair Cox is limited to +10% 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. Alastair Cox: 52%, Ivan Fisher: 77%. Reduce level confidence based on how unexpected the result is. Alastair Cox: 37%, Ivan Fisher: 55%. 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 Alastair Cox: 966, level confidence: 37%. Final level for Ivan Fisher: 433, level confidence: 55%. Notes
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