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Login: | Explaining level changesDivision 1: Redland Winter Lynx v University of Bristol Chicken Dinners (Thu 09 Nov 2017)Match played between Ruth Drysdale (home) and Alice 'The Tinwomen' Greswold (away).Match won by Ruth Drysdale. Result: 9-2,9-2,9-1. Starting level for Ruth Drysdale: 542, level confidence: 89%. Set manually. Starting level for Alice 'The Tinwomen' Greswold: 350, level confidence: 44%. Ruth Drysdale to win as she is currently playing 55% better than Alice 'The Tinwomen' Greswold. Ruth Drysdale won all of the games and 84% 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 134% (english scoring). These are weighted and combined to calculate that Ruth Drysdale played 134% better than Alice 'The Tinwomen' Greswold in this match. Assuming that any level changes are shared between both players, for this result it looks like Ruth Drysdale actually played at a level of 666 and Alice 'The Tinwomen' Greswold at a level of 285. Without any damping, both players would need to be adjusted by 23% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 18% and 18% 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 +8.9% and Alice 'The Tinwomen' Greswold changes to -18%. After applying standard match damping, the adjustment for Ruth Drysdale becomes +5.9% and for Alice 'The Tinwomen' Greswold becomes -10.3%. Apply match/event weighting of 75% for 'Womens Ladies Winter 2017/2018' so the adjustment for Ruth Drysdale is +4.4% and for Alice 'The Tinwomen' Greswold is -7.5%. 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 Alice 'The Tinwomen' Greswold is limited to -5.8% 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. Ruth Drysdale: 94%, Alice 'The Tinwomen' Greswold: 66%. Reduce level confidence based on how unexpected the result is. Ruth Drysdale: 77%, Alice 'The Tinwomen' Greswold: 54%. A final adjustment of +0.1% 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: 564, level confidence: 77%. Final level for Alice 'The Tinwomen' Greswold: 333, level confidence: 54%. Notes
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