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Login: | Explaining level changesHarry Farrer v Paul Wilcox (Sun 26 Apr 2015)Match won by Harry Farrer. Result: 9-3,9-4,9-0.Starting level for Harry Farrer: 430, level confidence: 66%. Starting level for Paul Wilcox: 409, level confidence: 65%. Harry Farrer to win as he is currently playing 5% better than Paul Wilcox. Harry Farrer won all of the games and 79% 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 97% (english scoring). These are weighted and combined to calculate that Harry Farrer played 97% better than Paul Wilcox in this match. Harry Farrer has played significantly better in this match than his level suggests and this is backed up by his last three results so use accelerated level adjustment to get his level right more quickly. As a result, his pre-match level has been increased to 504. The remaining calculations use this as his level coming in to this match. Assuming that any level changes are shared between both players, for this result it looks like Harry Farrer actually played at a level of 637 and Paul Wilcox at a level of 323. Without any damping, both players would need to be adjusted by 26% 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 Harry Farrer changes to +23% and Paul Wilcox changes to -24%. After applying standard match damping, the adjustment for Harry Farrer becomes +12.7% and for Paul Wilcox becomes -13%. Apply match/event weighting of 50% for 'Kingsdown & Horfield Boxes' so the adjustment for Harry Farrer is +6.3% and for Paul Wilcox is -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 Paul Wilcox 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. Including the accelerated level adjustment, the total adjustment for Harry Farrer is +25%. Increase level confidence due to one more match played. Harry Farrer: 81%, Paul Wilcox: 80%. Reduce level confidence based on how unexpected the result is. Harry Farrer: 59%, Paul Wilcox: 59%. 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 Harry Farrer: 536, level confidence: 59%. Final level for Paul Wilcox: 397, level confidence: 59%. Notes
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