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Login: | Explaining level changesDivision 1: Redland Winter Jaguars v University of Bristol Chicken Dinners (Thu 04 Apr 2019)Match played between Ruth Drysdale (home) and Esme Hedley (away).Match won by Ruth Drysdale. Result: 15-8,15-6,15-4. Starting level for Ruth Drysdale: 648, level confidence: 85%. Set manually. Starting level for Esme Hedley: 515, level confidence: 64%. Ruth Drysdale to win as she is currently playing 26% better than Esme Hedley. Ruth Drysdale won all of the games and 71% 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 150% (PAR scoring). These are weighted and combined to calculate that Ruth Drysdale played 150% better than Esme Hedley in this match. Assuming that any level changes are shared between both players, for this result it looks like Ruth Drysdale actually played at a level of 913 and Esme Hedley at a level of 365. Without any damping, both players would need to be adjusted by 41% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 36% and 36% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Ruth Drysdale changes to +27% and Esme Hedley changes to -36%. After applying standard match damping, the adjustment for Ruth Drysdale becomes +14.3% and for Esme Hedley becomes -18%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2018/2019' so the adjustment for Ruth Drysdale is +10.8% and for Esme Hedley is -13%. 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 Ruth Drysdale is limited to +10% and Esme Hedley 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. Ruth Drysdale: 92%, Esme Hedley: 80%. Reduce level confidence based on how unexpected the result is. Ruth Drysdale: 65%, Esme Hedley: 57%. A final adjustment of -0.5% 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 Ruth Drysdale: 707, level confidence: 65%. Final level for Esme Hedley: 489, level confidence: 57%. Notes
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