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Login: | Explaining level changesDivision 2: University of Bath Ladies A v Workout Harbourside A (Thu 02 Mar 2017)Match played between Alice Richards (home) and Emma Coughlan (away).Match won by Emma Coughlan. Result: 2-9,9-7,0-9,4-9:1-9,1-9,2-9:7-9,7-9,7-9:2-9,0-9,0-9:?-?. Starting level for Alice Richards: 692, level confidence: 70%. Set manually. Starting level for Emma Coughlan: 1,394, level confidence: 68%. Emma Coughlan to win as she is currently playing 101% better than Alice Richards. Emma Coughlan won 75% of the games and 69% of the points. This games result would be expected if she was better by around 25%. This points result would be expected if she was better by around 51% (english scoring). These are weighted and combined to calculate that Emma Coughlan played 34% better than Alice Richards in this match. Due to the difference between the players' levels, allow for the likelihood that Emma Coughlan was taking it easy by anything up to 13%. This gives her an allowed level range for this match between 1,030 and 1,394 without affecting her level. As Emma Coughlan has played below her allowed range at 976, her level reduction is 5.6% before damping. On the assumption that Emma Coughlan would normally have been playing at level 1,219 (based on typical behaviour), Alice Richards played better than expected and therefore gains a pre-damping level increase of 15%. Allowing for the difference in level between the players, the adjustments have been reduced to 3.9% and 10.2% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Emma Coughlan changes to -3.9% and Alice Richards changes to +9.9%. After applying standard match damping, the adjustment for Emma Coughlan becomes -3% and for Alice Richards becomes +6.4%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016/2017' so the adjustment for Emma Coughlan is -2.3% and for Alice Richards is +4.8%. Increase level confidence due to one more match played. Emma Coughlan: 82%, Alice Richards: 84%. Reduce level confidence based on how unexpected the result is. Emma Coughlan: 67%, Alice Richards: 68%. 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 Alice Richards: 720, level confidence: 68%. Final level for Emma Coughlan: 1,367, level confidence: 67%. Notes
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