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Login: | Explaining level changesDivision 2A: Redwood v Kingsdown (Wed 24 Feb 2010)Match played between Geoff Leeson (home) and Lachlan Ayres (away).Match won by Geoff Leeson. Result: 9-4,9-4,9-4:9-0,9-7,9-1:10-8,6-9,6-9,9-2,9-1:6-9,0-9,9-1,9-4,9-6:9-1,9-6,9-0. Starting level for Geoff Leeson: 1,044, level confidence: 67%. Starting level for Lachlan Ayres: 923, level confidence: 81%. Set manually. Geoff Leeson to win as he is currently playing 13% better than Lachlan Ayres. Geoff Leeson won all of the games and 69% 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 51% (english scoring). These are weighted and combined to calculate that Geoff Leeson played 52% better than Lachlan Ayres in this match. Assuming that any level changes are shared between both players, for this result it looks like Geoff Leeson actually played at a level of 1,212 and Lachlan Ayres at a level of 795. Without any damping, both players would need to be adjusted by 16% 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 Geoff Leeson changes to +15% and Lachlan Ayres changes to -12%. After applying standard match damping, the adjustment for Geoff Leeson becomes +8.7% and for Lachlan Ayres becomes -7.6%. Apply match/event weighting of 75% for 'Mixed Spring 2009 / 2010' so the adjustment for Geoff Leeson is +6.5% and for Lachlan Ayres is -5.6%. 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 Lachlan Ayres 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. Geoff Leeson: 82%, Lachlan Ayres: 90%. Reduce level confidence based on how unexpected the result is. Geoff Leeson: 71%, Lachlan Ayres: 77%. A final adjustment of +0.9% 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 Geoff Leeson: 1,110, level confidence: 71%. Final level for Lachlan Ayres: 897, level confidence: 77%. Notes
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