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Login: | Explaining level changesNev Saunders v James Cowan (Sun 24 Mar 2019)Match won by Nev Saunders. Result: 9-0,9-0,9-2.Starting level for Nev Saunders: 1,757, level confidence: 73%. Set manually. Starting level for James Cowan: 1,043, level confidence: 76%. Set manually. Nev Saunders to win as he is currently playing 68% better than James Cowan. Nev Saunders won all of the games and 93% 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 278% (english scoring). These are weighted and combined to calculate that Nev Saunders played 278% better than James Cowan in this match. Assuming that any level changes are shared between both players, for this result it looks like Nev Saunders actually played at a level of 2,632 and James Cowan at a level of 696. Without any damping, both players would need to be adjusted by 50% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 37% and 37% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Nev Saunders changes to +37% and James Cowan changes to -35%. After applying standard match damping, the adjustment for Nev Saunders becomes +14.7% and for James Cowan becomes -17%. Apply match/event weighting of 50% for 'Redland Green Boxes' so the adjustment for Nev Saunders is +7.3% and for James Cowan is -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 James Cowan 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. Nev Saunders: 85%, James Cowan: 87%. Reduce level confidence based on how unexpected the result is. Nev Saunders: 57%, James Cowan: 58%. A final adjustment of +0.8% 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 Nev Saunders: 1,894, level confidence: 57%. Final level for James Cowan: 1,004, level confidence: 58%. Notes
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