Another View of All-Time AFL Team MARS Ratings Post the 2013 Season

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Recently I'd been noticing some traffic to the site from the Big Footy website where the Forum members had been discussing the relative strengths of Bulldogs teams across VFL/AFL history. That, coupled with my continuing desire to become more proficient in the ggplot2 R package of Hadley Wickham, dragged me out of my off-season blog malaise to perform the analyses underpinning this current posting.
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Building Your Own Team Rating System

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Just before the 2nd Round of 2008 I created MAFL's Team Ratings System, MARS, never suspecting that I'd still be writing about it 5 years later. At the time, I described MARS in the newsletter for that week in a document still available from the Newsletters 2005-2008 section section of this website (it's linked under the "MAFL The Early Years" menu item in the navigation bar on the right of screen). Since then, MARS, as much to my surprise as I think to anyone's, has been a key input to the Line Funds that have operated in each of the ensuing years.
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To Win A Grand Final You Must First Lead

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History suggests that, as the higher-Rated "Home" team, Hawthorn must lead early and lead well if it is to be confident of success in Saturday's Grand Final, and not assume that its superior Rating will allow it to come back from any substantial deficit.
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Team Ratings, Bookmaker Prices and the Recent Predictability of Finals

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Last weekend saw three of four underdogs prevail in the first week of the Finals. Based on the data I have, you'd need to go back to 2006 to find a more surprising Week 1 of the Finals and, as highlighted in the previous blog, no matter how far you went back you wouldn't find a bigger upset than Port Adelaide's defeat of the Pies.
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Prime Motivation: An Analysis of Prime Numbers in AFL Scoring

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Earlier this week, the TED talk of Australian radio broadcaster, comedian and self-confessed number geek Adam Spencer was posted online. In it he explains his fascination with prime numbers, in particular the discovery of "monster primes", which got me to wondering about the prevalence of prime numbers amongst football scores.
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Is Class More or Less Important In AFL Finals?

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You'll hear it said about sport that class emerges when it's needed most. If that applies to football then you'd expect that better teams would be more likely to win games in the Finals than they are games in the regular home-and-away season.
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And the Best and Worst VFL/AFL Teams of All-Time Are ...

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I've promised for a while now to create MARS Ratings for the entire history of the VFL/AFL and with some time away from home over Easter, I'm now able to deliver on that promise.
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Defensive and Offensive Abilities : Do They Persist Across Seasons?

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In the previous blog we reviewed the relationship between teams' winning percentages in one season and their winning percentages in subsequent seasons. We found that the relationship was moderate to strong from one season to the next and then tapered off fairly quickly over the course of the next couple of seasons so that, by the time a season was three years distant, it told us relatively little about a team's likely winning percentage. There is, of course, an inextricable link between winning and scoring, and in this blog we'll investigate the temporal relationships in teams' scoring in much the same way as we investigated the temporal relationships in teams' winning in that previous blog.
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What Do Seasons Past Tell Us About Seasons Present?

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I've looked before at the consistency in the winning records of teams across seasons but I've not previously reported the results in any great detail. For today's blog I've stitched together the end of season home-and-away ladders for every year from 1897 to 2012, which has allowed me to create a complete time series of the performances for every team that's ever played.
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How Many Quarters Will the Home Team Win?

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In this last of a series of posts on creating estimates for teams' chances of winning portions of an AFL game I'll be comparing a statistical model of the Home Team's probability of winning 0, 1, 2, 3 or all 4 quarters with the heuristically-derived model used in the most-recent post.
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Evidence for Intra-Game Momentum in AFL Games

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So often in the commentary for an AFL game we hear it said that one team or the other "has the momentum going into the break". This blog sets out to examine this claim - how we might interpret it quantitatively and, given that interpretation, whether or not it's true.
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Lead Changes as a Measure of Game Competitiveness

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The final victory margin is one measure of how close a contest was, but it can sometimes mislead when the team that's in front midway through the final term piles on a slew of late goals against a progressively more demoralised opponent, improving its percentage in so doing, but also erasing any trace of the fact that the game might have been a close-run thing throughout the first three-and-a-half or more quarters.
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Characterising AFL Seasons

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I can think of a number of ways that an AFL season might be characterised but for today's blog I'm going to call on a modelling approach that I used back in 2010, which is based on Brownian motion and which was inspired by a JASA paper from Hal S Stern.
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2012 - Recent History of MARS Ratings and Ladder Positions

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This year we finished the home-and-away season with 11 teams carrying MARS Ratings of over 1,000, hinting at the competitiveness we saw for positions in the Finals. MARS Ratings are zero-sum though, so a large crop of highly-rated teams necessitates a smaller crop of lowly-rated ones
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Measures of Game Competitiveness

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All this analysis of victory margins, and a query from Dan about a recent blog post, has had me wondering about victory margin as a measure of the competitiveness of games. Within a given era - say 10 years or so - during which the average points scored per game won't vary by too much, victory margin seems to be a reasonable proxy for competitiveness, but if you want to consider a broader swathe of AFL history, it strikes me as being deficient.
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Margins of Victory Across the Seasons

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This year MAFL Investors will be taking on the TAB bookmaker in a new arena by attempting to pick the final victory margin for each game within a 10-point range. Having not wagered in this market I've no bedrock of intuitions - nor misconceptions - about it yet; I thought I'd start with a little historical analysis.
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Underachieving and Overachieving Teams

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A couple of blogs back I described some win production functions, which relate a team's winning percentage in the home-and-away season to characteristics of its scoring during that season, in particular to its rate of scoring shot production and its conversion of those scoring shots relative to its opponents'.
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Win Production Functions for AFL Teams - 1897 to 2010

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Right now I'm reading Wayne L Winston's Mathletics, a book about the use of fairly simple mathematics and sports statistics to gain insights into the results of American sports. Inspired by this book, in particular by a piece on Pythagorean Expectation which relates the season-long winning percentage of a baseball team to the total runs that it's scored and allowed, I wondered if an AFL team's win percentage could be similarly predicted by a handful of summary statistics about its own and its opponents' scoring.
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