Sam Chedzow v Kristian Richards (Sat 09 Jan 2010)
Match won by Sam Chedzow. Result: 8-11,11-6,10-12,11-9,13-11.
Starting level for
Sam Chedzow:
71, level confidence: 10%.
Starting level for
Kristian Richards:
69, level confidence: 10%.
Sam Chedzow to win as he is currently playing
3% better than Kristian Richards.
Sam Chedzow won 60% of the games and 52% of the points.
This
games result would be expected if he was better by around 10%.
This
points result would be expected if he was better by around 8% (PAR scoring).
These are weighted and combined to calculate that Sam Chedzow played
10% better than Kristian Richards in this match.
Special case for levels < 100 as these are often players who are new to the game and getting better fast. Levels can change quickly for these players and a default level increase of 1 has been added to both players for playing another match.
Without any limiting, both players would need to be adjusted by 3%. The level change for Sam Chedzow has not been limited and has increased to
74. The level change for Kristian Richards has not been limited and has decreased to
68.
Increase level confidence due to one more match played. Sam Chedzow: 22%, Kristian Richards: 22%.
Reduce level confidence based on how much adjustment is needed. Sam Chedzow: 21%, Kristian Richards: 21%.
A final adjustment of +12% 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 Sam Chedzow:
83, level confidence: 21%.
Final level for Kristian Richards:
76, level confidence: 21%.
Notes
- This calculation is done in two main parts; first work out the adjustment needed to match the results
and then apply damping. This means that levels should always be 'about right' but the time taken
to get there or the volatility is dependent on the damping.
- A level also has 'level confidence' which drops if players haven't played for a long time or have had
enexpected results. As low confidence levels adjust more quickly than high confidence levels, it allows
these players to find their level more quickly without impacting their opponent's level too much.
- Point scores are used as well as game scores for accuracy - particularly important for 3-0 results -
though we can work with game scores only too, albeit with more damping.
- Mismatched players are allowed for - you don't have to hammer your opponent. See explanation above
if this applies to this match.
- The section on damping is where we still have some options. We have recently made a change to damp
league matches more than tournament matches and box matches even more than that. This gives added
weight to the more important matches.
- There are occasional, very small adjustments made to all players to keep the averages constant which
are not covered here.
- You don't get a bonus just for winning - if you want to go up you have to play better
than expected against your opponent.
- We have spent more than 5 years fine tuning the level calculations based on tens of thousands of match results
and a great deal of feedback from players, team captains and coaches. It's the most usable and accurate
ranking system there is in any sport, let alone squash.
- For a more complete explanation of how levels are calculated (on which this system is based) see the help file
here.
- If you have thoughts/opinions on the above or any feedback on the way levels are calculated or updated,
please contact us.
We welcome all feedback, although we are keen squash players ourselves and would pefer to be on-court than
in front of a screen so please be patient and please do try to see if your question has already been
answered on the help page. We are unable to
answer questions about hard anyone played in their match - we only get to see the results - and if your
level didn't increase as expected please make sure you've looked at the above explanation before
contacting us. If you want to go up the levels, train harder, listen to your coach and win more points.
Or just be incredibly talented!