|
Menu
Login: | Explaining level changesDivision 2: Keynsham A v University of Bath 3 (Wed 26 Feb 2020)Match played between John Davies (home) and Billy ‘The Better’ Colley (away).Match won by Billy ‘The Better’ Colley. Result: 6-15,6-15,7-15. Starting level for John Davies: 1,226, level confidence: 61%. Starting level for Billy ‘The Better’ Colley: 1,138, level confidence: 79%. Set manually. John Davies to win as he is currently playing 8% better than Billy ‘The Better’ Colley. Billy ‘The Better’ Colley won all of the games and 70% 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 137% (PAR scoring). These are weighted and combined to calculate that Billy ‘The Better’ Colley played 137% better than John Davies in this match. Assuming that any level changes are shared between both players, for this result it looks like Billy ‘The Better’ Colley actually played at a level of 1,818 and John Davies at a level of 768. Without any damping, both players would need to be adjusted by 60% to match this result. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Billy ‘The Better’ Colley changes to +44% and John Davies changes to -57%. After applying standard match damping, the adjustment for Billy ‘The Better’ Colley becomes +20.6% and for John Davies becomes -25%. Apply match/event weighting of 75% for 'Mixed Spring 2019/2020' so the adjustment for Billy ‘The Better’ Colley is +15% and for John Davies is -17%. 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 Billy ‘The Better’ Colley is limited to +10% and John Davies 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. Billy ‘The Better’ Colley: 89%, John Davies: 78%. Reduce level confidence based on how unexpected the result is. Billy ‘The Better’ Colley: 56%, John Davies: 49%. A final adjustment of -0.2% 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 John Davies: 1,166, level confidence: 49%. Final level for Billy ‘The Better’ Colley: 1,250, level confidence: 56%. Notes
|