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Login: | Explaining level changesDivision 2: Thornbury v Weston A (Thu 31 Jan 2013)Match played between Pam Brunt (home) and Sue Roberts (away).Match won by Sue Roberts. Result: 2-9,3-9,2-9. Starting level for Pam Brunt: 176, level confidence: 53%. Starting level for Sue Roberts: 540, level confidence: 65%. Sue Roberts to win as she is currently playing 207% better than Pam Brunt. Sue Roberts won all of the games and 79% 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 97% (english scoring). These are weighted and combined to calculate that Sue Roberts played 97% better than Pam Brunt in this match. Due to the difference between the players' levels, allow for the likelihood that Sue Roberts was taking it easy by anything up to 25%. This gives her an allowed level range for this match between 281 and 540 without affecting her level. In this case, Sue Roberts played at level 374 and remained within her allowed range so her level will not be adjusted. On the assumption that Sue Roberts would normally have been playing at level 404 (based on typical behaviour), Pam Brunt played better than expected and therefore gains a pre-damping level increase of 8%. Allowing for the difference in level between the players, the adjustments have been reduced to 0% and 4.5% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Sue Roberts changes to 0% and Pam Brunt changes to +4.5%. After applying standard match damping, the adjustment for Sue Roberts becomes 0% and for Pam Brunt becomes +3.7%. Apply match/event weighting of 75% for 'Womens Women's Autumn 2012' so the adjustment for Sue Roberts is 0% and for Pam Brunt is +2.8%. Increase level confidence due to one more match played. Sue Roberts: 81%, Pam Brunt: 73%. Reduce level confidence based on how unexpected the result is. Sue Roberts: 65%, Pam Brunt: 58%. 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 Pam Brunt: 181, level confidence: 58%. Final level for Sue Roberts: 539, level confidence: 65%. Notes
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