Wednesday, 18 March 2015

Overview

This blog is a result of the work of Dr Tim Chartier, I would highly recommend his courses on Udemy or Edx. He has set up a web site to rank the College men's basketball teams here - http://marchmathness.davidson.edu

If you want to understand how he ranks the teams read below:

Most sport teams are ranked by the simple Win/Loss record or winning percentage. So a team that wins 7 out of 10 games (70%) has a higher ranking than a team that wins 4 out of 10 (40%) games.

However, this simple calculation does not take into account that each team can play different teams (conferences/strength of competition) or that teams do not play each other the same number of times (as in my favorite sport - Australian Rules Football (AFL) - "Oh when the SAINTS....").

Two popular sports ranking systems are the Colley Method and the Massey Method. A comparison of the different methods from previous AFL seasons are in the tables below. The "Finals" or playoff method was the eventual outcome, Massey predicted this more accurately than the other methods (a short 3 minute video on the "Sports Data and Software" page shows how this Massey ranking was obtained).

Massey has the current Australian Football rankings - https://www.masseyratings.com/aufl/ratings


Wins/Losses 2016FinalsMasseyColley
SydneyWesternBulldogsSydneyHawthorn
GeelongSydneyWesternSydneySydney
HawthornGeelongGeelongGeelong
WesternSydneyWesternSydneyAdelaideAdelaide
AdelaideHawthornWestCoastWesternSydney
West CoastAdelaideHawthornWest Coast
WesternBulldogsWest CoastWesternBulldogsWesternBulldogs
North MelbourneNorth MelbourneNorth MelbourneNorth Melbourne

Wins/Losses 2015FinalsMasseyColley
FremantleHawthornHawthornFremantle
West CoastWest CoastWest CoastWest Coast
HawthornFremantleSydney SwansSydney Swans
Sydney SwansNorth MelbourneFremantleHawthorn
RichmondSydney SwansAdelaideWest Bulldogs
West BulldogsAdelaideRichmondRichmond
AdelaideRichmondWest BulldogsAdelaide
North MelbourneWest BulldogsPort AdelaideNorth Melbourne
Wins/Losses 2014FinalsMasseyColley
Sydney SwansHawthornHawthornHawthorn
HawthornSydney SwansSydney SwansGeelong Cats
Geelong CatsPort AdelaidePort AdelaideSydney Swans
FremantleFremantleFremantleFremantle
Port AdelaideNorth MelbourneNorth MelbournePort Adelaide
North MelbourneGeelong CatsGeelong CatsNorth Melbourne
EssendonEssendonWest CoastEssendon
RichmondRichmondAdelaideRichmond


These 2 methods are used extensively in Collegiate Basketball and Football in USA and in a tournament called "March Madness" where the top 64 out of about 350 collegiate men's basketball teams play off in a knock out competition.

Each method uses High School Maths (linear algebra, matrices, least squares and network graphs), which  makes these methods really useful to teach students and adds to the movement of "making Maths more relevant and interesting". I will outline some class activities within the Colley and Massey page links (on the left).

As an introduction, the letters represent each team and for example, the arrow pointing from Team A to Team B, means Team A beat Team B. How would you rank these teams?






Please post or contact me via my Google+ profile below if you have any interesting tournaments - I would like to create a work book for students.

Sports results can be downloaded and used in programs to rank the teams - click here.


Some other good AFL Stats sites -

http://www.matterofstats.com/

http://www.tedsport.com.au/

http://makingthenut.com/

http://www.espn.com/espn/feature/story/_/id/19348021/footy-forensics-afl-changing-game-trends-2017

http://afltables.com/afl/afl_index.html