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Login: | Explaining level changesDivision 2: University of Bristol Llamas v David Lloyd A (Thu 19 Mar 2015)Match played between Verity Ashford (home) and Jane Baker (away).Match won by Jane Baker. Result: 6-9,6-9,4-9. Starting level for Verity Ashford: 116, level confidence: 72%. Set manually. Starting level for Jane Baker: 247, level confidence: 65%. Jane Baker to win as she is currently playing 113% better than Verity Ashford. Jane Baker won all of the games and 63% 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 32% (english scoring). These are weighted and combined to calculate that Jane Baker played 40% better than Verity Ashford in this match. Due to the difference between the players' levels, allow for the likelihood that Jane Baker was taking it easy by anything up to 14%. This gives her an allowed level range for this match between 176 and 247 without affecting her level. As Jane Baker has played below her allowed range at 169, her level reduction is 4.2% before damping. On the assumption that Jane Baker would normally have been playing at level 212 (based on typical behaviour), Verity Ashford played better than expected and therefore gains a pre-damping level increase of 14%. Allowing for the difference in level between the players, the adjustments have been reduced to 2.8% and 9.7% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Jane Baker changes to -2.8% and Verity Ashford changes to +8.9%. After applying standard match damping, the adjustment for Jane Baker becomes -2.8% and for Verity Ashford becomes +5.9%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016 2014/2015' so the adjustment for Jane Baker is -2.1% and for Verity Ashford is +4.4%. Increase level confidence due to one more match played. Jane Baker: 81%, Verity Ashford: 85%. Reduce level confidence based on how unexpected the result is. Jane Baker: 66%, Verity Ashford: 69%. 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 Verity Ashford: 120, level confidence: 69%. Final level for Jane Baker: 243, level confidence: 66%. Notes
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