Current Rankings

March 2010 Rankings - based on your best 20 events over the past 12 months

Background

Our resident mathematics wizard, Ray Howe, collects stats from all of the street-orienteering series and collates these periodically. While he started out to do this to measure his own performance (and to track the spiral dive in this as he gets older), he thought the rest of us might be interested to see what it says about us. While the results might not be quite what you expect, read on - Ray provides a lucid argument for the approach put forward, but would be more than happy to take feedback and apply this to future rankings.

Over to Ray for more details...

Purpose

Rankings are designed to provide Street-O competitors with a yearly measure of their performances. The rankings reflect quality of performance and quantity of performances. The better the performance the higher the ranking and the greater the participation the higher the probability of increasing the ranking. The rankings can (1) measure performance change, (2) be objective basis for grading competitors and (3) act as a motivational tool for improvement.

Presentation

Rankings are listed in 4 categories: (1) Male Runners (2) Female Runners (3) Male Walkers (4) Female Walkers. Rankings are determined by the best 20 adjusted event scores for each competitor over the preceding 12 months. Rankings are adjusted on the first day of each month. For example, on the 1st October 2008 the adjusted event scores for September 2007 are replaced with the adjusted event scores for September 2008.

Calculation

Adjusted event scores are calculated by multiplying each event score by 2 factors (Factor A and Factor B). Factor A (Runners) reflects the duration or distance of the course selected. The longer the event, the higher the factor. (A course = 1.00, B course = 0.94, C course = 0.88). D and E courses are not considered. Factor A (Walkers) is always 1.00 as the there is no event choice available in PW events. Factor B (Runners and Walkers) reflects the number of competitors in the event. The more competitors the higher the factor. ( 1-5 competitors = 1.00, 6-10 competitors = 1.01, 11-15 competitors = 1.02, 16-20 competitors = 1.03, etc…)

Examples

Tim scores 87 in a B course event with 22 competitors.

Tim's adjusted event score = Event score x Factor A x Factor B = 87 x 0.94 x 1.04 = 85.1

Sally scores 87 in a A course event with 17 competitors.

Sally's adjusted event score = Event score x Factor A x Factor B = 87 x 1.00 x 1.03 = 89.6

Cherie scores 77 in a PW event with 43 competitors.

Cherie's adjusted event score = Event score x Factor A x Factor B = 77 x 1.00 x 1.08 = 83.2

Hey this can't be right - who do I complain to?

Understand that Ray is the first to note that the approach used produces some interesting (perhaps unusual) results. He also recognises that the weights that he assigns to courses, the loadings for higher participation and the kickback that he gives to me for publishing the list here ;-) can all be fine-tuned as we get more experience. If you want to improve your rating you could of course lose weight, train more and run more frequently - if this doesn't work, bring grossly fattening stuff to cake-O and then encourage other runners in your course/category to tuck in. If you're really desperate - by all means send an incredibly polite note to him at Hey Ray - I have a question . Ray notes that including money could improve your rating - but that he hasn't worked out a weighting for this yet...so please don't do this until he's had time to work out the exchange rates.

In the meantime, enjoy this new service provided by one of our keener runners....