|
Menu
Login: | Explaining level changesPremier A: Rhiwbina v Lansdown 1 (Wed 08 Mar 2023)Match played between Alex Rowlands (home) and John Welton (away).Match won by John Welton. Result: 5-11,5-11,1-11. Starting level for Alex Rowlands: 6,034, level confidence: 45%. Starting level for John Welton: 11,367, level confidence: 76%. Set manually. John Welton to win as he is currently playing 88% better than Alex Rowlands. John Welton won all of the games and 75% 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 200% (PAR scoring). These are weighted and combined to calculate that John Welton played 200% better than Alex Rowlands in this match. Assuming that any level changes are shared between both players, for this result it looks like John Welton actually played at a level of 14,345 and Alex Rowlands at a level of 4,782. Without any damping, both players would need to be adjusted by 26% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 18% and 18% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for John Welton changes to +10.9% and Alex Rowlands changes to -18%. After applying standard match damping, the adjustment for John Welton becomes +3.3% and for Alex Rowlands becomes -5.8%. Given John Welton's level and the type of match played, an additional damping of 21% has been applied to his level change. Given Alex Rowlands's level and the type of match played, an additional damping of 4.3% has been applied to his level change. Apply match/event weighting of 75% for 'Mixed Spring 2022/2023' so the adjustment for John Welton is +2% and for Alex Rowlands is -4.1%. Increase level confidence due to one more match played. John Welton: 87%, Alex Rowlands: 67%. Reduce level confidence based on how unexpected the result is. John Welton: 69%, Alex Rowlands: 53%. A final adjustment of +4.8% 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 Alex Rowlands: 6,161, level confidence: 53%. Final level for John Welton: 11,991, level confidence: 69%. Notes
|