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Login: | Explaining level changesDivision 2: Redwood v Redland Winter Lynx (Thu 14 Mar 2013)Match played between Nicky Leeson (home) and Jacqui Clinch (away).Match won by Nicky Leeson. Result: 9-7,9-4,9-3:9-6,4-9,9-6,9-3:6-9,8-10,10-8,4-9:9-6,9-2,9-7:?-?. Starting level for Nicky Leeson: 379, level confidence: 30%. Starting level for Jacqui Clinch: 457, level confidence: 27%. Jacqui Clinch to win as she is currently playing 21% better than Nicky Leeson. Nicky Leeson won all of the games and 66% of the points. This games result would be expected if she was better by around 55% or more. This points result would be expected if she was better by around 41% (english scoring). These are weighted and combined to calculate that Nicky Leeson played 46% better than Jacqui Clinch in this match. Assuming that any level changes are shared between both players, for this result it looks like Nicky Leeson actually played at a level of 502 and Jacqui Clinch at a level of 345. Without any damping, both players would need to be adjusted by 33% 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 Nicky Leeson changes to +27% and Jacqui Clinch changes to -29%. After applying standard match damping, the adjustment for Nicky Leeson becomes +14.3% and for Jacqui Clinch becomes -15%. Apply match/event weighting of 75% for 'Womens Women's Autumn 2012' so the adjustment for Nicky Leeson is +10.7% and for Jacqui Clinch 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 Nicky Leeson is limited to +10% and Jacqui Clinch 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. Nicky Leeson: 54%, Jacqui Clinch: 52%. Reduce level confidence based on how unexpected the result is. Nicky Leeson: 41%, Jacqui Clinch: 39%. 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 Nicky Leeson: 416, level confidence: 41%. Final level for Jacqui Clinch: 435, level confidence: 39%. Notes
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