|
Menu
Login: | Explaining level changesPremier C: Redland Capybaras v Thornbury A (Wed 16 Feb 2022)Match played between Nathan Day (home) and Ian Johnson (away).Match won by Nathan Day. Result: 11-6,11-4,11-7. Starting level for Nathan Day: 2,611, level confidence: 70%. Starting level for Ian Johnson: 2,022, level confidence: 64%. Nathan Day to win as he is currently playing 29% better than Ian Johnson. Nathan Day won all of the games and 66% 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 94% (PAR scoring). These are weighted and combined to calculate that Nathan Day played 94% better than Ian Johnson in this match. Assuming that any level changes are shared between both players, for this result it looks like Nathan Day actually played at a level of 3,201 and Ian Johnson at a level of 1,649. Without any damping, both players would need to be adjusted by 23% to match this result. Allowing for the difference in level between the players, the adjustments have been reduced to 20% and 20% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Nathan Day changes to +18% and Ian Johnson changes to -20%. After applying standard match damping, the adjustment for Nathan Day becomes +7.1% and for Ian Johnson becomes -8.4%. Apply match/event weighting of 75% for 'Mixed Spring 2021/2022' so the adjustment for Nathan Day is +5.4% and for Ian Johnson is -6.1%. 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 Ian Johnson 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. Nathan Day: 84%, Ian Johnson: 80%. Reduce level confidence based on how unexpected the result is. Nathan Day: 68%, Ian Johnson: 65%. 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 Nathan Day: 2,747, level confidence: 68%. Final level for Ian Johnson: 1,923, level confidence: 65%. Notes
|