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Login: | Explaining level changesDivision 2: David Lloyd A v University of Bristol Beasts (Thu 23 Feb 2017)Match played between Emma Phillips (home) and Freya Bell (away).Match won by Emma Phillips. Result: 9-7,3-9,7-9,9-3,9-2:9-6,10-8,9-4:7-9,7-9,3-9:7-9,2-9,6-9:?-?. Starting level for Emma Phillips: 318, level confidence: 68%. Starting level for Freya Bell: 170, level confidence: 62%. Emma Phillips to win as she is currently playing 87% better than Freya Bell. Emma Phillips won 60% of the games and 55% of the points. This games result would be expected if she was better by around 10%. This points result would be expected if she was better by around 11% (english scoring). These are weighted and combined to calculate that Emma Phillips played 10% better than Freya Bell in this match. Due to the difference between the players' levels, allow for the likelihood that Emma Phillips was taking it easy by anything up to 10%. This gives her an allowed level range for this match between 249 and 318 without affecting her level. As Emma Phillips has played below her allowed range at 216, her level reduction is 15% before damping. On the assumption that Emma Phillips would normally have been playing at level 285 (based on typical behaviour), Freya Bell played better than expected and therefore gains a pre-damping level increase of 23%. Allowing for the difference in level between the players, the adjustments have been reduced to 11% and 17% 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 Phillips changes to -9.8% and Freya Bell changes to +17%. After applying standard match damping, the adjustment for Emma Phillips becomes -6.4% and for Freya Bell becomes +9.6%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016/2017' so the adjustment for Emma Phillips is -4.7% and for Freya Bell is +7.2%. Increase level confidence due to one more match played. Emma Phillips: 83%, Freya Bell: 79%. Reduce level confidence based on how unexpected the result is. Emma Phillips: 64%, Freya Bell: 60%. A final adjustment of -2.6% 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 Emma Phillips: 292, level confidence: 64%. Final level for Freya Bell: 180, level confidence: 60%. Notes
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