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Login: | Explaining level changesDivision 2: University of Bath Ladies A v Weston A (Thu 06 Mar 2014)Match played between Francisca Lopes Dos Santos (home) and Quita Colston (away).Match won by Francisca Lopes Dos Santos. Result: 9-0,9-1,9-3:9-2,9-2,9-7:6-9,10-9,9-3,9-6:9-1,9-7,10-8:9-3,9-6,6-9,7-9,9-4. Starting level for Francisca Lopes Dos Santos: 575, level confidence: 69%. Starting level for Quita Colston: 491, level confidence: 73%. Set manually. Francisca Lopes Dos Santos to win as she is currently playing 17% better than Quita Colston. Francisca Lopes Dos Santos won all of the games and 87% of the points. This games result would be expected if she was better by around 55% or more. This points result would be expected if she was better by around 164% (english scoring). These are weighted and combined to calculate that Francisca Lopes Dos Santos played 164% better than Quita Colston in this match. Assuming that any level changes are shared between both players, for this result it looks like Francisca Lopes Dos Santos actually played at a level of 863 and Quita Colston at a level of 327. Without any damping, both players would need to be adjusted by 50% 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 Francisca Lopes Dos Santos changes to +46% and Quita Colston changes to -42%. After applying standard match damping, the adjustment for Francisca Lopes Dos Santos becomes +22.5% and for Quita Colston becomes -21%. Apply match/event weighting of 75% for 'Womens Women's Spring 2013/2014' so the adjustment for Francisca Lopes Dos Santos is +17% and for Quita Colston is -15%. 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 Francisca Lopes Dos Santos is limited to +10% and Quita Colston 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. Francisca Lopes Dos Santos: 83%, Quita Colston: 85%. Reduce level confidence based on how unexpected the result is. Francisca Lopes Dos Santos: 55%, Quita Colston: 57%. 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 Francisca Lopes Dos Santos: 632, level confidence: 55%. Final level for Quita Colston: 467, level confidence: 57%. Notes
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