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Login: | Explaining level changesDivision 3: Lansdown Avon County Girls A v Weston A (Thu 17 Mar 2016)Match played between Gemma Bedford (home) and Abbey Scott (away).Match won by Becky Watkins. Result: 1-9,0-9,0-9. Starting level for Gemma Bedford: 112, level confidence: 54%. Starting level for Becky Watkins: 188, level confidence: 61%. Becky Watkins to win as she is currently playing 68% better than Gemma Bedford. Becky Watkins won all of the games and 96% 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 379% (english scoring). These are weighted and combined to calculate that Becky Watkins played 379% better than Gemma Bedford in this match. Assuming that any level changes are shared between both players, for this result it looks like Becky Watkins actually played at a level of 318 and Gemma Bedford at a level of 66. Without any damping, both players would need to be adjusted by 69% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 50% and 50% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Becky Watkins changes to +44% and Gemma Bedford changes to -50%. After applying standard match damping, the adjustment for Becky Watkins becomes +21.8% and for Gemma Bedford becomes -24%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016' so the adjustment for Becky Watkins is +16% and for Gemma Bedford is -17%. 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 Becky Watkins is limited to +10% and Gemma Bedford 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. Increase level confidence due to one more match played. Becky Watkins: 78%, Gemma Bedford: 74%. Reduce level confidence based on how unexpected the result is. Becky Watkins: 46%, Gemma Bedford: 44%. 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 Gemma Bedford: 107, level confidence: 44%. Final level for Becky Watkins: 206, level confidence: 46%. Notes
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