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Login: | Explaining level changesDivision 2: David Lloyd A v University of Bristol Beasts (Thu 08 Mar 2018)Match played between Emma Phillips (home) and Holly Thompson (away).Match won by Holly Thompson. Result: 1-9,5-9,2-9. Starting level for Emma Phillips: 294, level confidence: 68%. Starting level for Holly Thompson: 287, level confidence: 64%. Emma Phillips to win as she is currently playing 2% better than Holly Thompson. Holly Thompson won all of the games and 77% 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 86% (english scoring). These are weighted and combined to calculate that Holly Thompson played 86% better than Emma Phillips in this match. Holly Thompson has played significantly better in this match than her level suggests and this is backed up by his last three results so use accelerated level adjustment to get her level right more quickly. As a result, her pre-match level has been increased to 320. The remaining calculations use this as her level coming in to this match. Assuming that any level changes are shared between both players, for this result it looks like Holly Thompson actually played at a level of 418 and Emma Phillips at a level of 225. Without any damping, both players would need to be adjusted by 31% 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 Holly Thompson changes to +29% and Emma Phillips changes to -27%. After applying standard match damping, the adjustment for Holly Thompson becomes +15.4% and for Emma Phillips becomes -14%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2019 2017/2018' so the adjustment for Holly Thompson is +12% and for Emma Phillips is -10.4%. 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 Holly Thompson is limited to +10% and Emma Phillips 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. Including the accelerated level adjustment, the total adjustment for Holly Thompson is +23%. Increase level confidence due to one more match played. Holly Thompson: 80%, Emma Phillips: 83%. Reduce level confidence based on how unexpected the result is. Holly Thompson: 58%, Emma Phillips: 60%. A final adjustment of -0.4% 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: 281, level confidence: 60%. Final level for Holly Thompson: 348, level confidence: 58%. Notes
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