We have imported nearly 1.5 million results covering the last 15 years from New Zealand tournaments, leagues and pennants into SquashLevels. Our goals are:
- Provide an accurate assessment of every player's playing level for every match over that entire period
- Map those player levels to the familiar grades that have been in use in New Zealand for many years
- Bring the advantages of accurate and dynamic ratings to everyone who plays squash in New Zealand
- Provide MySquash with all this data so it can be displayed on that system too
The process we followed was along these lines. We worked very closely with the federation throughout.
- Imported all the results into our development system
- Allowed our system to do a first pass at calibration
- Ran our tools to help identify as many players as we could that play both within New Zealand and also in other countries as these players help us guide the calibration further.
- During this process we did find that we needed to apply a little more damping for the calibration to settle.
- Mapped our player levels to iSquash points and vice-versa allowing us to align the two systems as closely as we could - acknowledging that they are different systems but wanting to minimise change.
- Mapped our player levels to the existing grading system
- Reviewed the final levels and rankings as best we could and agreed that were ready for the launch at the end of January along with MySquash
- Copied everything over to the live system for the launch
And that was the first time everyone got to see it in detail!
With a little time under our belt since the launch and some welcome feedback we have learned more about some of the specifics of New Zealand!
- There is a five month gap between the end of the season and the start of the next
- The season typically kicks off with a series of tournaments to help everyone get back up to speed again
- The extra damping we applied (see above) was preventing us from keeping up with some of the up and coming juniors who continue to improve really quickly.
- The levels at the lower end are probably a bit low compared to those outside of New Zealand
So we've taken this opportunity - before the levels become too ingrained - to make some algorithmic changes to allow for these specifics:
- We have increased the damping on those start of season tounaments as there were some quite significant level changes going on as the system quickly adjusted to the playing levels of many players who hadn't played for months! This effectively provides a grace period as everyone gets back into it.
- We have reduced the damping in general so we can keep up with the juniors. This will also mean player levels can change more each match for everyone else.
- We have adjusted the levels at the lower end using a sliding scale all the way up to the higher level players who are not changing.
- We have re-mapped the grades so they have the same distribution as before and so most players should still be on the same grades they were before.
With these changes we are confident that we have been able to apply our global rating system to New Zealand which not only provides accurate and dynamic ratings but also allows you to be part of the world wide squash community. If you play squash in New Zealand, you will have a world rating!