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Login: | Explaining level changesDivision 2B: Weston String Strokers v Gordano B (Wed 05 Feb 2014)Match played between Rob Fryer (home) and Rob Ritchie (away).Match won by Rob Ritchie. Result: 1-9,4-9,0-9. Starting level for Rob Fryer: 581, level confidence: 39%. Starting level for Rob Ritchie: 606, level confidence: 56%. Rob Ritchie to win as he is currently playing 4% better than Rob Fryer. Rob Ritchie won all of the games and 84% 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 134% (english scoring). These are weighted and combined to calculate that Rob Ritchie played 134% better than Rob Fryer in this match. Rob Ritchie 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 692. 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 Rob Ritchie actually played at a level of 970 and Rob Fryer at a level of 415. Without any damping, both players would need to be adjusted by 40% 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 Rob Ritchie changes to +25% and Rob Fryer changes to -36%. After applying standard match damping, the adjustment for Rob Ritchie becomes +13.7% and for Rob Fryer becomes -19%. Apply match/event weighting of 75% for 'Mixed Spring 2013/2014' so the adjustment for Rob Ritchie is +10.2% and for Rob Fryer is -13%. 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 Rob Fryer 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. Including the accelerated level adjustment, the total adjustment for Rob Ritchie is +26%. Increase level confidence due to one more match played. Rob Ritchie: 75%, Rob Fryer: 63%. Reduce level confidence based on how unexpected the result is. Rob Ritchie: 50%, Rob Fryer: 42%. 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 Rob Fryer: 527, level confidence: 42%. Final level for Rob Ritchie: 758, level confidence: 50%. Notes
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