Wednesday, August 31, 2011

The 2011-2012 Regression Based Analysis

I really want to beat Justin. Not just "sort of" beat Justin. I want to wipe that ACC smirk of his face and really give him the business.

The bad news is that RBA is up to 73.2% accuracy since 2000 while TFG is at 74.0%, implying that Justin gets approximately 5.3 games per year more than I do. However, I have been making significant strides on the difference between expected accuracy and actual accuracy. As of today, the difference between my predicted and actual performance is down to 0.2%, meaning that I miss 1.3 games per year more than I think I should. This manifests itself as an improvement in the confidence metric, implying that I may yet beat him in the TFD pick 'em pool.

The major update to RBA comes in the form of conference versus non-conference home field advantage. Teams that play each other every year are less phased by harsh environments, whereas teams that infrequently travel into opposing stadiums are more rattled. Based upon my data since 2000, home field advantage is worth approximately 1.9 PPH in conference games. In contrast, home field advantage is worth 3.6 PPH in non-conference games.

I experimented with a lot of different home field advantage metrics throughout the summer, including per-team advantage, linear regressions by strength, and linear regression by strength difference. These features generally caused drops by 1% accuracy or more. Justin suggests that attendance makes a difference, but I don't have a way to get these numbers into the algorithm.

One of the ideas that Justin and I have thrown around is changing predictors when we detect a lot of mispredictions. I took a shot at this by pruning history when encountering N consecutive mispredictions and had very poor results. In general, I don't tend to miss many consecutive picks. Furthermore, by time we detect the change (presumably due to injury, suspension, or whatever), the change has corrected itself, meaning that we miss even more games later.

In summary, there have been major experiments but only minor tweaks in the RBA algorithm during the summer of 2011. However, I'm relatively confident that RBA will keep it close during the 2nd Annual TFD College Football Pick 'Em.

Tuesday, August 30, 2011

Welcome to the 2011-2012 season

Welcome to the 2011-2012 college football season!

After a lengthy slumber the Tempo-Free Gridiron is back for the new year, and the theme of this year is "More Content." Our goal for this year is provide you with more interesting and more frequent updates to keep you coming back for more. In addition to a new look, we've got a slew of new regular features for our readers throughout the year. These include:

  • Tuesday Trivia. Each Tuesday in September will explore a random trivia topic. We've done this before, but now we're making it official.
  • Undefeated Countdown. We did this last year in a somewhat ad-hoc manner, but this year we're doing it every other Thursday starting in October. We'll examine the remaining undefeated teams, their possible road to a perfect season, and the main obstacles in their way.
  • Conference Projections. Starting in October we'll have a weekly breakdown of the 12 conferences, spread out over three days. These breakdowns will include both the current standings and the projected final standings. The schedule will be:
    • Tuesday: ACC, Big East, Conference USA, Independents
    • Wednesday: Big Ten, Big XII, Mid-Atlantic, Mountain West
    • Thursday: SEC, Pac-12, Sun Belt, WAC
  • Games of the Week. Along with weekly predictions we'll focus on specific Saturday games that are interesting in some way or another. These may be the top-billed games on ESPN that week, or they may be a showdown of two middle-of-the-pack teams that pit an explosive offense against an impressive defense -- the Unstoppable Force/Immovable Object (UFIO) game -- or simply the game that's expected to turn into a shootout.
This is all on top of our weekly predictions, discussions, rankings, and complete bowl coverage that we've provided the previous years. Keep an eye on the blog or follow us on Twitter.