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Login: | Explaining level changesDivision 2: University of Bath Ladies A v University of Bristol Beasts (Thu 30 Mar 2017)Match played between Alice O'Keeffe (home) and Lydia Shepherd (away).Match won by Lydia Shepherd. Result: 0-9,5-9,3-9. Starting level for Alice O'Keeffe: 100, level confidence: 51%. Starting level for Lydia Shepherd: 226, level confidence: 66%. Lydia Shepherd to win as she is currently playing 126% better than Alice O'Keeffe. Lydia Shepherd 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 Lydia Shepherd played 86% better than Alice O'Keeffe in this match. Due to the difference between the players' levels, allow for the likelihood that Lydia Shepherd was taking it easy by anything up to 16%. This gives her an allowed level range for this match between 154 and 226 without affecting her level. In this case, Lydia Shepherd played at level 188 and remained within her allowed range so her level will not be adjusted. On the assumption that Lydia Shepherd would normally have been playing at level 191 (based on typical behaviour), Alice O'Keeffe played better than expected and therefore gains a pre-damping level increase of 1.2%. Allowing for the difference in level between the players, the adjustments have been reduced to 0% and 0.8% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Lydia Shepherd changes to 0% and Alice O'Keeffe changes to +0.8%. After applying standard match damping, the adjustment for Lydia Shepherd becomes 0% and for Alice O'Keeffe becomes +0.8%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016/2017' so the adjustment for Lydia Shepherd is 0% and for Alice O'Keeffe is +0.6%. Increase level confidence due to one more match played. Lydia Shepherd: 81%, Alice O'Keeffe: 72%. Reduce level confidence based on how unexpected the result is. Lydia Shepherd: 74%, Alice O'Keeffe: 65%. A final adjustment of -0.5% 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 Alice O'Keeffe: 100, level confidence: 65%. Final level for Lydia Shepherd: 226, level confidence: 74%. Notes
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