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Login: | Explaining level changesDivision 2B: Bradley Stoke Squash Club A v Kingsdown Stallions (Wed 18 Mar 2015)Match played between George Morgan (home) and Josh ‘Racing Snake’ Sweet (away).Match won by George Morgan. Result: 9-1,9-0,9-4. Starting level for George Morgan: 1,686, level confidence: 77%. Set manually. Starting level for Josh ‘Racing Snake’ Sweet: 1,505, level confidence: 56%. George Morgan to win as he is currently playing 12% better than Josh ‘Racing Snake’ Sweet. George Morgan 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 George Morgan played 134% better than Josh ‘Racing Snake’ Sweet in this match. Assuming that any level changes are shared between both players, for this result it looks like George Morgan actually played at a level of 2,437 and Josh ‘Racing Snake’ Sweet at a level of 1,041. Without any damping, both players would need to be adjusted by 45% 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 George Morgan changes to +30% and Josh ‘Racing Snake’ Sweet changes to -42%. After applying standard match damping, the adjustment for George Morgan becomes +12.8% and for Josh ‘Racing Snake’ Sweet becomes -17%. Apply match/event weighting of 75% for 'Mixed Spring 2014/2015' so the adjustment for George Morgan is +9.6% and for Josh ‘Racing Snake’ Sweet 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 Josh ‘Racing Snake’ Sweet 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. George Morgan: 88%, Josh ‘Racing Snake’ Sweet: 75%. Reduce level confidence based on how unexpected the result is. George Morgan: 61%, Josh ‘Racing Snake’ Sweet: 52%. 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 George Morgan: 1,845, level confidence: 61%. Final level for Josh ‘Racing Snake’ Sweet: 1,431, level confidence: 52%. Notes
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