The following websites apply advanced statistical research to football. Think SABR but for football instead. It is harder to count things in football than in other sports like baseball. So these websites really are pushing development into new areas while baseball analysts have "been there, done that." for their sport. If you are interested in advanced statistical analysis for football, check out these websites and read up on what it is they are trying to quantify with their new statistical measures. The hard part is translating this information into fantasy play. Some sites may help in this regard while others do not. But it is worth a look if you are interested in this sort of research. Some sites offer their content for free while others require payment.
Advanced NFL Stats
Advisor (Accuscore)
Analytic Football
Beatpaths
BudGoodeSports
Cold Hard Football Facts.com
Drive-By Football
ESPN: Stat & Info: NFL
FFToday
Football Commentary
Football Outsiders
HyperStat Online Statistics Textbook
Journal of Quantitative Analysis in Sports
Mathletics
MIT Sloan Sports Analytics Conference
Pigskin Revolution
Pro-Football Reference
Sports Data Hub
SportsQuant
Stathead
The Football Scientist
The Sports Economist
Yahoo! NFL Stats
Individual Research Articles of Note
How Important is Age?
Most Valuable Position: What's more important, a running back or a center? A safety or a cornerback?
Running Back Turnover and How It Affects Your Fantasy Draft
Outside Foxborough - The Injury Effect
Outside Foxborough - The Injury Effect, Part 2
What's YACo got to do with it?
