Here we are after two weeks of NFL play with plenty of interesting trends starting to develop. Surprise names like the 49ers, Titans, Colts, and Jaguars find themselves in the top ten. Three of the top eleven teams reside in the NFC West. Green Bay is back among the leaders, but on the strength of their defense, not their offense. Baltimore is riding the strength of their offense even more than their still talented defense.
The Patriots are the Patriots. How do you improve on a nearly perfect rating the week prior? Play the Miami Dolphins. Both the Ravens and the Patriots have incredibly weak strength of schedule so far, but they have blown out their opponents in 3 of the 4 combined games.
The Seahawks are dragged down a bit by playing two inferior teams as well. Pittsburgh and Cincinnati rank as two of the worst teams in the league so far. Remove SOS from the rankings formula, and the Seahawks rise to 8th overall.
Seattle has a microscopic point differential of only three points. They are only able to rank this well on the strength of their MVP candidate quarterback who is storming out of the gates with a 134.5 passer rating.
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.