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Login: | Explaining level changesPremier C: BAWA A v Lansdown 7 (Wed 28 Jan 2015)Match played between Tom Gogarty (home) and Lee Jacobs (away).Match won by Tom Gogarty. Result: 9-2,9-0,9-2. Starting level for Tom Gogarty: 3,300, level confidence: 76%. Set manually. Starting level for Lee Jacobs: 2,250, level confidence: 54%. Tom Gogarty to win as he is currently playing 47% better than Lee Jacobs. Tom Gogarty won all of the games and 87% 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 164% (english scoring). These are weighted and combined to calculate that Tom Gogarty played 164% better than Lee Jacobs in this match. Assuming that any level changes are shared between both players, for this result it looks like Tom Gogarty actually played at a level of 4,427 and Lee Jacobs at a level of 1,677. Without any damping, both players would need to be adjusted by 34% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 27% and 27% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Tom Gogarty changes to +19% and Lee Jacobs changes to -27%. After applying standard match damping, the adjustment for Tom Gogarty becomes +7% and for Lee Jacobs becomes -10.6%. Apply match/event weighting of 75% for 'Mixed Spring 2014/2015' so the adjustment for Tom Gogarty is +5.3% and for Lee Jacobs is -7.8%. 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 Lee Jacobs 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. Tom Gogarty: 87%, Lee Jacobs: 73%. Reduce level confidence based on how unexpected the result is. Tom Gogarty: 65%, Lee Jacobs: 55%. 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 Tom Gogarty: 3,470, level confidence: 65%. Final level for Lee Jacobs: 2,140, level confidence: 55%. Notes
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