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Login: | Explaining level changesDivision 2: Thornbury C v BAWA / Kingswood (Wed 16 Mar 2016)Match played between Chris Hutchence (home) and Ian Pittas (away).Match won by Ian Pittas. Result: 6-9,5-9,8-10. Starting level for Chris Hutchence: 2,233, level confidence: 80%. Set manually. Starting level for Ian Pittas: 1,939, level confidence: 81%. Set manually. Chris Hutchence to win as he is currently playing 15% better than Ian Pittas. Ian Pittas won all of the games and 60% 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 24% (english scoring). These are weighted and combined to calculate that Ian Pittas played 34% better than Chris Hutchence in this match. Assuming that any level changes are shared between both players, for this result it looks like Ian Pittas actually played at a level of 2,411 and Chris Hutchence at a level of 1,796. Without any damping, both players would need to be adjusted by 24% to match this result. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Ian Pittas changes to +22% and Chris Hutchence changes to -22%. After applying standard match damping, the adjustment for Ian Pittas becomes +9.4% and for Chris Hutchence becomes -9%. Apply match/event weighting of 75% for 'Mixed Spring 2015/2016' so the adjustment for Ian Pittas is +7% and for Chris Hutchence is -6.6%. 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 Chris Hutchence 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. Ian Pittas: 90%, Chris Hutchence: 90%. Reduce level confidence based on how unexpected the result is. Ian Pittas: 73%, Chris Hutchence: 72%. A final adjustment of -3.2% 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 Chris Hutchence: 2,027, level confidence: 72%. Final level for Ian Pittas: 2,044, level confidence: 73%. Notes
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