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Login: | Explaining level changesDivision 3A: Hutton Moor A v Kingswood Originals (Wed 12 Mar 2008)Match played between Simon Farance (home) and Andy Milbourne (away).Match won by Simon Farance. Result: 9-7,9-7,9-1. Starting level for Simon Farance: 458, level confidence: 74%. Set manually. Starting level for Andy Milbourne: 591, level confidence: 65%. Andy Milbourne to win as he is currently playing 29% better than Simon Farance. Simon Farance won all of the games and 64% 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 35% (english scoring). These are weighted and combined to calculate that Simon Farance played 42% better than Andy Milbourne in this match. An upset! Assuming that any level changes are shared between both players, for this result it looks like Simon Farance actually played at a level of 619 and Andy Milbourne at a level of 437. Without any damping, both players would need to be adjusted by 35% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 30% and 30% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Simon Farance changes to +27% and Andy Milbourne changes to -30%. After applying standard match damping, the adjustment for Simon Farance becomes +14.2% and for Andy Milbourne becomes -16%. Apply match/event weighting of 75% for 'Mixed Spring 2008' so the adjustment for Simon Farance is +10.6% and for Andy Milbourne is -11%. 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 Simon Farance is limited to +10% and Andy Milbourne 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. Simon Farance: 86%, Andy Milbourne: 80%. Reduce level confidence based on how unexpected the result is. Simon Farance: 64%, Andy Milbourne: 59%. 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 Simon Farance: 503, level confidence: 64%. Final level for Andy Milbourne: 562, level confidence: 59%. Notes
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