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Login: | Explaining level changesDivision 2: University of Bristol Beasts v University of Bath Ladies A (Tue 28 Feb 2017)Match played between Amber Courtier (home) and Philippa 'Lilphilgainz' Burns (away).Match won by Amber Courtier. Result: 9-0,9-0,9-3. Starting level for Amber Courtier: 97, level confidence: 61%. Starting level for Philippa 'Lilphilgainz' Burns: 136, level confidence: 10%. Philippa 'Lilphilgainz' Burns to win as he is currently playing 40% better than Amber Courtier. Amber Courtier won all of the games and 90% 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 209% (english scoring). These are weighted and combined to calculate that Amber Courtier played 209% better than Philippa 'Lilphilgainz' Burns in this match. An upset! Assuming that any level changes are shared between both players, for this result it looks like Amber Courtier actually played at a level of 202 and Philippa 'Lilphilgainz' Burns at a level of 65. Without any damping, both players would need to be adjusted by 108% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 86% and 86% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Amber Courtier changes to +14% and Philippa 'Lilphilgainz' Burns changes to -86%. After applying standard match damping, the adjustment for Amber Courtier becomes +8.4% and for Philippa 'Lilphilgainz' Burns becomes -38%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016/2017' so the adjustment for Amber Courtier is +6.3% and for Philippa 'Lilphilgainz' Burns is -26%. 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 Philippa 'Lilphilgainz' Burns is limited to -10% 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. Increase level confidence due to one more match played. Amber Courtier: 78%, Philippa 'Lilphilgainz' Burns: 32%. Reduce level confidence based on how unexpected the result is. Amber Courtier: 38%, Philippa 'Lilphilgainz' Burns: 15%. A final adjustment of -4.4% 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 Amber Courtier: 122, level confidence: 38%. Final level for Philippa 'Lilphilgainz' Burns: 96, level confidence: 15%. Notes
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