Menu | Explaining level changesDavid Campbell v Alison Cordery (Wed 10 Jan 2024)Match won by David Campbell. Result: 11-4,11-5,11-4.Starting level for David Campbell: 442, level confidence: 54%. Starting level for Alison Cordery: 290, level confidence: 55%. David Campbell to win as he is currently playing 52% better than Alison Cordery. David Campbell won all of the games and 72% 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 154% (PAR scoring). These are weighted and combined to calculate that David Campbell played 154% better than Alison Cordery in this match. Assuming that any level changes are shared between both players, for this result it looks like David Campbell actually played at a level of 570 and Alison Cordery at a level of 225. Without any damping, both players would need to be adjusted by 29% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 22% and 23% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for David Campbell changes to +22% and Alison Cordery changes to -23%. After applying standard match damping, the adjustment for David Campbell becomes +12.3% and for Alison Cordery becomes -13%. Apply match/event weighting of 50% for 'Fair Oak Boxes' so the adjustment for David Campbell is +6.2% and for Alison Cordery 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 Alison Cordery 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. David Campbell: 74%, Alison Cordery: 74%. Reduce level confidence based on how unexpected the result is. David Campbell: 57%, Alison Cordery: 57%. 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 David Campbell: 468, level confidence: 57%. Final level for Alison Cordery: 276, level confidence: 57%. Notes
|