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Login: | Explaining level changesPremier A: David Lloyd v University of Bath 4 (Wed 19 Mar 2008)Match played between Geoff Watson (home) and Andy Hibbert (away).Match won by Geoff Watson. Result: 9-3,9-5,9-1. Starting level for Geoff Watson: 2,787, level confidence: 77%. Set manually. Starting level for Andy Hibbert: 1,179, level confidence: 50%. Geoff Watson to win as he is currently playing 136% better than Andy Hibbert. Geoff Watson won all of the games and 75% of the points. This games result would be expected if he was better by around 55% or more. This points result would be expected if he was better by around 76% (english scoring). These are weighted and combined to calculate that Geoff Watson played 76% better than Andy Hibbert in this match. Due to the difference between the players' levels, allow for the likelihood that Geoff Watson was taking it easy by anything up to 17%. This gives him an allowed level range for this match between 1,833 and 2,787 without affecting his level. In this case, Geoff Watson played at level 2,191 and remained within his allowed range so his level will not be adjusted. On the assumption that Geoff Watson would normally have been playing at level 2,313 (based on typical behaviour), Andy Hibbert played better than expected and therefore gains a pre-damping level increase of 5.6%. Allowing for the difference in level between the players, the adjustments have been reduced to 0% and 3.6% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Geoff Watson changes to 0% and Andy Hibbert changes to +3.6%. After applying standard match damping, the adjustment for Geoff Watson becomes 0% and for Andy Hibbert becomes +3.1%. Apply match/event weighting of 75% for 'Mixed Spring 2008' so the adjustment for Geoff Watson is 0% and for Andy Hibbert is +2.3%. Increase level confidence due to one more match played. Geoff Watson: 88%, Andy Hibbert: 71%. Reduce level confidence based on how unexpected the result is. Geoff Watson: 76%, Andy Hibbert: 61%. 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 Geoff Watson: 2,783, level confidence: 76%. Final level for Andy Hibbert: 1,204, level confidence: 61%. Notes
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