Anna Ashwell v Laura Wood (Mon 15 Mar 2010)
Match won by Laura Wood. Result: 4-15,7-15,4-15.
Starting level for
Anna Ashwell:
231, level confidence: 77%. Set manually.
Starting level for
Laura Wood:
382, level confidence: 74%. Set manually.
Laura Wood to win as he is currently playing
65% better than Anna Ashwell.
Laura Wood won all of the games and 75% 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 200% (PAR scoring).
These are weighted and combined to calculate that Laura Wood played
200% better than Anna Ashwell in this match.
Assuming that any level changes are shared between both players, for this result it looks like Laura Wood actually played at a level of
515 and Anna Ashwell at a level of
172. 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 26% and 26% respectively.
Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Laura Wood changes to +26% and Anna Ashwell changes to -25%.
After applying standard match damping, the adjustment for Laura Wood becomes +13.9% and for Anna Ashwell becomes -13%.
Apply match/event weighting of 75% for 'Hertfordshire League 2009/2010' so the adjustment for Laura Wood is +10.5% and for Anna Ashwell is -9.7%.
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 Anna Ashwell 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. Laura Wood: 86%, Anna Ashwell: 88%. Reduce level confidence based on how unexpected the result is. Laura Wood: 64%, Anna Ashwell: 65%.
Final level for Anna Ashwell:
220, level confidence: 65%.
Final level for Laura Wood:
420, level confidence: 64%.