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Login: | Explaining level changesAlex Kilbride v Alexander Webb (Sun 14 Nov 2010)Match won by Alexander Webb. Result: 6-11,11-6,9-11,12-10,2-11.Starting level for Alex Kilbride: 148, level confidence: 45%. Starting level for Alexander Webb: 540, level confidence: 44%. Alexander Webb to win as he is currently playing 265% better than Alex Kilbride. Alexander Webb won 60% of the games and 55% of the points. This games result would be expected if he was better by around 10%. This points result would be expected if he was better by around 23% (PAR scoring). These are weighted and combined to calculate that Alexander Webb played 13% better than Alex Kilbride in this match. Due to the difference between the players' levels, allow for the likelihood that Alexander Webb was taking it easy by anything up to 31%. This gives him an allowed level range for this match between 256 and 540 without affecting his level. As Alexander Webb has played below his allowed range at 207, his level reduction is 24% before damping. On the assumption that Alexander Webb would normally have been playing at level 372 (based on typical behaviour), Alex Kilbride played better than expected and therefore gains a pre-damping level increase of 49%. Allowing for the difference in level between the players, the adjustments have been reduced to 12% and 23% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Alexander Webb changes to -12% and Alex Kilbride changes to +23%. After applying standard match damping, the adjustment for Alexander Webb becomes -7.4% and for Alex Kilbride becomes +13%. Apply match/event weighting of 100% for 'Avon Junior Open' so the adjustment is unchanged. 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 Alexander Webb is limited to -5% and Alex Kilbride is limited to +10% 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. Alexander Webb: 67%, Alex Kilbride: 67%. Reduce level confidence based on how unexpected the result is. Alexander Webb: 37%, Alex Kilbride: 37%. Final level for Alex Kilbride: 163, level confidence: 37%. Final level for Alexander Webb: 514, level confidence: 37%. Notes
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