Lots of action this week across the NFL hierarchy. Seattle and Denver manage to improve their team strength despite sub-par performances. The Saints are marching. The Panther keep moving up, and the Bengals jump up an amazing 13.7 points after their blowout victory.
Arizona improved nearly the same amount, showing the Seahawks win their last week may have been more impressive than many would give them credit for.
It is fair to wonder how Seattle gained points during one of their worst games of the year. They did it by increasing their passer rating differential. Despite the terrible offensive performance, Russell Wilson did end with a 100+ rating and Kellen Clemens was held under 40.0. That has been a better indicator of team strength historically than sack differential or total yardage differential, and it’s not close. Very odd game, and odd result here.
Note: If you are having problems viewing the rankings below, try this link.(Leave a comment if it doesn’t work for you!)
Trying a bar chart of the rankings to see if that is easier to read. This view helps to give you a view of how teams are grouped together. You will generally see tiers of strength develop as the season wears on.
RANKINGS EXPLAINED
Power rankings are always debatable. I don’t buy into the gut feel methods most places use to determine their rankings, so I developed a formula a few years back that attempts to take at least some of the subjectivity out of the discussion. My approach was simple, I measured offensive and defensive efficiency based on the Yards Per Carry (YPC) and Yards Per Attempt (YPA), as well as points scored and points allowed. The formula to calculate “Team Strength” was as follows:
(YPC (offense) + YPA (offense) + Avg Pts/Game Scored) – (YPC (defense) + YPA (defense)+ Avg Pts/Game Allowed)
The formula has proven to be a pretty accurate predictor of success, but I am always looking for ways to improve it. I read a great article on ColdHardFootballFacts.com. There was one gem in there about predicting championship teams. The article mentioned passer rating differential as the “mother of all stats.” A full 69 of 72 champions have ranked in the Top 10 in this statistic. It is a stat after my own heart, as I believe offensive and defensive efficiency is the key measurable outside of point differential. Turnovers would factor in there as well, but I am not convinced a team has as much control over that. My power rankings use YPA and YPC differentials. I went ahead and replaced the YPA with offensive and defensive passer rating, to give me this:
(YPC (offense) + Passer Rating (offense) + Avg Pts/Game Scored) – (OPP YPC (defense) + OPP Passer Rating (defense)+ OPP Avg Pts/Game)