Wednesday, July 27, 2011

While the newswires are in overdrive with head-spinning roster moves, one of the biggest questions we have heading into the 2011 NFL season is--where do teams rank and who has the toughest schedule?

However, before we get to that, the more important question that should be asked is how do we arrive at our rankings?


#1 - 2010 Power rankings

The first phase is made up of four key components.  Team power ratings, strength of schedule (SoS), how they performed relative to that schedule, and variance. 

I use my own system for my team power ratings, but everyone will have different criteria and weigh factors differently.  Ultimately, the results at the end of the day will determine how good or bad a system is and it's vital to constantly adapt to what's working and what isn't.

However, a power rating or SoS is never indicative of anything by itself.  It's key to evaluate how teams did with the schedule they had.  This will tease out which teams over/underperformed, who had padded/dampened stats, and where future value lies.

It's also important to determine how much variance accounted for the results.  The teams that are supposed to win don't also do so.   How much of their success/failure had to do with luck, injuries, coaching, etc?  

#2 - Adjusted Power Rankings for 2011.

Once you've got a good grip on where teams stand heading into free agency and training camp, it won't be very difficult to tweak the rankings for the coming season.  There are many factors that would cause a change in rankings.  Significant roster moves.  Coaching changes (especially those that bring a new scheme).   Players returning from injury.  Declining/ascending players.  Draft picks.  Etc etc.

#3 - 2011 Strength of Schedule (SoS)

The SoS is perhaps the most deceiving set of rankings in all of football.  Even respected stat guys like Jeff Sagarin seem to take the easy way out.  The truth is, you can completely ignore these types of rankings due in large part to their inaccuracies.

Websites like ESPN blatantly state that their SoS is based on the previous season records, but you cannot simply look at team records and use that as your base of reference.  This approach puts you 5 steps behind before things even start.

True SoS rankings involve going back and rating the strength of each opponent a team plays for that week they are playing.  Injuries, trends, luck, etc must be accounted for due to the large variability within a season/week/game.  You should be asking yourself, did team A play the Cowboys in the first half of the season, or the last?  Are you giving the Bucs full credit for their final two wins when they played teams that pulled their starters?   How impressive was the Lions win over the Packers when Rodgers left the game early with an injury?

By the time you account for this variance, custom SoS from 2010 looks drastically different than the one you see on ESPN or USAToday and custom power rankings will completely alter a SoS for 2011.

My power rankings and SoS from 2010.

SoS for 2011.