|
Menu
Login: | Explaining level changesDivision 2: University of Bristol Chicken Dinners v David Lloyd A (Thu 30 Mar 2017)Match played between Maddie Freeman (home) and Sue Lock (away).Match won by Maddie Freeman. Result: 9-0,9-3,9-5. Starting level for Maddie Freeman: 302, level confidence: 78%. Set manually. Starting level for Sue Lock: 289, level confidence: 76%. Set manually. Maddie Freeman to win as she is currently playing 4% better than Sue Lock. Maddie Freeman won all of the games and 77% of the points. This games result would be expected if she was better by around 55% or more. This points result would be expected if she was better by around 86% (english scoring). These are weighted and combined to calculate that Maddie Freeman played 86% better than Sue Lock in this match. Assuming that any level changes are shared between both players, for this result it looks like Maddie Freeman actually played at a level of 403 and Sue Lock at a level of 217. Without any damping, both players would need to be adjusted by 33% 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 Maddie Freeman changes to +32% and Sue Lock changes to -33%. After applying standard match damping, the adjustment for Maddie Freeman becomes +16.5% and for Sue Lock becomes -17%. Apply match/event weighting of 75% for 'Womens Ladies Spring 2016/2017' so the adjustment for Maddie Freeman is +12% and for Sue Lock is -12%. 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 Maddie Freeman is limited to +10% and Sue Lock 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. Maddie Freeman: 88%, Sue Lock: 87%. Reduce level confidence based on how unexpected the result is. Maddie Freeman: 66%, Sue Lock: 65%. A final adjustment of +1.4% 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 Maddie Freeman: 332, level confidence: 66%. Final level for Sue Lock: 283, level confidence: 65%. Notes
|