|
Menu
Login: | Explaining level changesDivision 3: Whitchurch Imperial A v University of Bath 3 (Wed 05 Oct 2016)Match played between Bill Hope (home) and Simon Brown (away).Match won by Simon Brown. Result: 1-9,0-9,1-9:9-5,4-9,9-3,9-4:9-5,10-9,4-9,9-5:1-9,5-9,2-9:7-9,0-9,5-9. Starting level for Bill Hope: 1,377, level confidence: 69%. Starting level for Simon Brown: 1,977, level confidence: 31%. Simon Brown to win as he is currently playing 44% better than Bill Hope. Simon Brown 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 Simon Brown played 278% better than Bill Hope in this match. Assuming that any level changes are shared between both players, for this result it looks like Simon Brown actually played at a level of 3,208 and Bill Hope at a level of 849. Without any damping, both players would need to be adjusted by 62% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 50% and 50% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Simon Brown changes to +50% and Bill Hope changes to -18%. After applying standard match damping, the adjustment for Simon Brown becomes +18.2% and for Bill Hope becomes -8.9%. Apply match/event weighting of 75% for 'Mixed Autumn 2016/2017' so the adjustment for Simon Brown is +14% and for Bill Hope is -6.6%. 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 Simon Brown is limited to +10% and Bill Hope 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. Simon Brown: 56%, Bill Hope: 83%. Reduce level confidence based on how unexpected the result is. Simon Brown: 35%, Bill Hope: 51%. A final adjustment of +0.4% 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 Bill Hope: 1,325, level confidence: 51%. Final level for Simon Brown: 2,171, level confidence: 35%. Notes
|