NFL Power Rankings Week 15: Chiefs Overtake Seahawks

The Seahawks loss to the Rams was bad enough to force them down a few notches in the rankings. That coincided with strong pushes from both the Chiefs and the Vikings, leaving Seattle out of the top five.

Seattle has faced the toughest schedule in the NFL to this point. So much is discussed about their minimal point differential. Very little is said about how impressive it is to be 11-3 against a schedule that tough. None of the other top four teams in terms of SOS have more than 8 wins on the year. Baltimore is 5th, but their SOS is almost half of Seattle’s.

The 49ers are 11th in SOS. New England is 16th.

Rankings Visualization

This view shows tiers of strength that develop over the course of the season.

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 (roughly 70% of the teams ranked in the Top 10 by week 3 make the playoffs), 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) As of September 23, 2014, I have added a strength of schedule component to the rankings as well.   As of November 22, 2016, I have increased the weighting of the run game and point differential. Yards per carry will be multiplied by 10 to make it more evenly weighted with the passer rating. It is still roughly half as important, but will have a greater impact. Point differential will be multiplied by two as it still should be among the most important aspects of measuring teams.