Measuring the Surprise in a Season's Results

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In the previous blog we looked at the average level of surprisals generated by teams and by team pairings across all of VFL/AFL history and during the most-recent seasons. Today, as promised in that blog, I'm going to analyse surprisals using the same general methodology, but by season.
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Which Teams Fare Better as Favourites?

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In this blog, the next is a series in which I've been exploring the all-time MARS Ratings I created for every game from the start of 1897 to the end of the 2012 season, I'll be looking at how well each team has performed depending on the relative strength of its opponent, as measured by their MARS Rating. So, for example, we'll consider how well Collingwood tends to do when playing a team it is assessed as being much stronger than, a little stronger than, about as capable as, and so on.
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The Greatest Upset Victories in VFL/AFL History (1897-2012)

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The Suns' victory over the Saints in the first round of the 2013 season was heralded as an "upset win" for the Suns and one of the greatest in their short history. Undoubtedly their win was unexpected, but even the bookmakers rated the Suns as only $3.75 chances, so it was hardly a Halley's comet-like occurrence.
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Team MARS Ratings Performance By Decade and Overall: 1897 to 2012

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In the previous blog on the topic of all-time MARS Ratings I explained the process I used to derive team Ratings across history and then identified those teams that had achieved the highest (Essendon) and lowest (Fitzroy) MARS Ratings ever. We know then which teams have burned brightest - and which flickered dimmest - across VFL/AFL history. In this blog I want to explore more extended bursts of talent or apparent lack of it.
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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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Does an Extra Day's Rest Matter in the Home and Away Season?

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Whenever the draw for a new season is revealed there's much discussion about the teams that face one another only once, about which teams need to travel interstate more than others, and about which teams are asked to play successive games with fewer days rest. There is in the discussion an implicit assumption that more days rest is better than fewer days rest but, to my knowledge, this is never supported by empirical analysis. It is, like much of the discussion about football, considered axiomatic. In this blog we'll assess how reasonable that assumption is.
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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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The Changing Nature of Home Team Probability

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The original motivation for this blog was to provide additional context for the previous blog on victory probabilities for portions of games. That blog looked at the relationship between the TAB Bookmaker's pre-game assessment of the Home team's chances and the subsequent success or otherwise of the Home team in portions - Quarters, Halfs and so on - of the game under review.
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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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1897 to 2011 : Winners v Losers - Leads, Scoring Shots and Conversion

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In the previous blog, among other things we analysed which quarter winning teams win. We might also ask about winnng teams, in what proportion of games do they trail at the end of a particular quarter, and how has this proportion tracked over the seasons.
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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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A First Look At Surprisals for 2011

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We first discussed surprisals back in 2009 (if you perform a site search using the term "surprisals" you'll be linked to a couple of PDFs as well as to a handful of blog posts on the topic) as a method for quantifying the surprise associated with the outcome of a football game.
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Predicting a Team's Winning Percentage for the Season

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In recent blogs where I've been posting about a win production function the goal has been to fit a team's season-long winning percentage as a function of its scoring statistics for that same season. What if, instead, our goal was to predict a team's winning percentage at the start of a season, using only scoring statistics from previous seasons?
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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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