|
Menu
Login: | Explaining level changesPremier A: Westbury David Lloyd A v Thornbury A (Wed 07 Nov 2018)Match played between Chris Lawrance (home) and Craig Webb (away).Match won by Craig Webb. Result: 5-11,2-11,4-11. Starting level for Chris Lawrance: 2,788, level confidence: 58%. Starting level for Craig Webb: 4,978, level confidence: 76%. Set manually. Craig Webb to win as he is currently playing 79% better than Chris Lawrance. Craig Webb 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 Craig Webb played 200% better than Chris Lawrance in this match. Assuming that any level changes are shared between both players, for this result it looks like Craig Webb actually played at a level of 6,453 and Chris Lawrance at a level of 2,151. Without any damping, both players would need to be adjusted by 30% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 21% and 21% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Craig Webb changes to +16% and Chris Lawrance changes to -21%. After applying standard match damping, the adjustment for Craig Webb becomes +5.5% and for Chris Lawrance becomes -8.1%. Apply match/event weighting of 75% for 'Mixed Autumn 2018/2019' so the adjustment for Craig Webb is +4.1% and for Chris Lawrance is -5.9%. 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 Lawrance 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. Craig Webb: 87%, Chris Lawrance: 76%. Reduce level confidence based on how unexpected the result is. Craig Webb: 67%, Chris Lawrance: 59%. A final adjustment of -2.1% 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 Chris Lawrance: 2,599, level confidence: 59%. Final level for Craig Webb: 5,084, level confidence: 67%. Notes
|