|
Menu
Login: | Explaining level changesAlisdair Wriglesworth v Richard Masom (Mon 27 Feb 2017)Match won by Richard Masom. Result: 5-9,9-10,6-9.Starting level for Alisdair Wriglesworth: 1,432, level confidence: 68%. Starting level for Richard Masom: 1,019, level confidence: 77%. Set manually. Alisdair Wriglesworth to win as he is currently playing 41% better than Richard Masom. Richard Masom won all of the games and 58% 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 18% (english scoring). These are weighted and combined to calculate that Richard Masom played 30% better than Alisdair Wriglesworth in this match. An upset! Assuming that any level changes are shared between both players, for this result it looks like Richard Masom actually played at a level of 1,378 and Alisdair Wriglesworth at a level of 1,059. Without any damping, both players would need to be adjusted by 35% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 29% and 29% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Richard Masom changes to +26% and Alisdair Wriglesworth changes to -29%. After applying standard match damping, the adjustment for Richard Masom becomes +13.6% and for Alisdair Wriglesworth becomes -13%. Apply match/event weighting of 50% for 'Redland Green Boxes' so the adjustment for Richard Masom is +6.8% and for Alisdair Wriglesworth is -6.2%. 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 Alisdair Wriglesworth 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. Richard Masom: 88%, Alisdair Wriglesworth: 83%. Reduce level confidence based on how unexpected the result is. Richard Masom: 65%, Alisdair Wriglesworth: 61%. A final adjustment of +1.3% 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 Alisdair Wriglesworth: 1,380, level confidence: 61%. Final level for Richard Masom: 1,103, level confidence: 65%. Notes
|