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Login: | Explaining level changesDivision 3: Redland Winter Pumas v University of Bath Ladies A (Thu 06 Feb 2020)Match played between Ruth Drysdale (home) and Elizabeth Mamchits (away).Match won by Ruth Drysdale. Result: 15-3,15-7,15-11:12-15,14-16,15-17:15-5,15-8,15-7:15-10,15-8,15-12. Starting level for Ruth Drysdale: 651, level confidence: 55%. Starting level for Elizabeth Mamchits: 215, level confidence: 10%. Ruth Drysdale to win as she is currently playing 203% better than Elizabeth Mamchits. Ruth Drysdale won all of the games and 68% 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 114% (PAR scoring). These are weighted and combined to calculate that Ruth Drysdale played 114% better than Elizabeth Mamchits in this match. Due to the difference between the players' levels, allow for the likelihood that Ruth Drysdale was taking it easy by anything up to 25%. This gives her an allowed level range for this match between 344 and 651 without affecting her level. In this case, Ruth Drysdale played at level 475 and remained within her allowed range so her level will not be adjusted. On the assumption that Ruth Drysdale would normally have been playing at level 490 (based on typical behaviour), Elizabeth Mamchits played better than expected and therefore gains a pre-damping level increase of 3.1%. Allowing for the difference in level between the players, the adjustments have been reduced to 0% and 1.8% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Ruth Drysdale changes to 0% and Elizabeth Mamchits changes to +1.8%. After applying standard match damping, the adjustment for Ruth Drysdale becomes 0% and for Elizabeth Mamchits becomes +1.8%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2019/2020' so the adjustment for Ruth Drysdale is 0% and for Elizabeth Mamchits is +1.3%. Increase level confidence due to one more match played. Ruth Drysdale: 74%, Elizabeth Mamchits: 32%. Reduce level confidence based on how unexpected the result is. Ruth Drysdale: 62%, Elizabeth Mamchits: 27%. A final adjustment of +18.9% 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 Ruth Drysdale: 651, level confidence: 62%. Final level for Elizabeth Mamchits: 308, level confidence: 27%. Notes
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