Wednesday, December 17, 2008

NFL Performance Rankings Week 15

Last week, we noted the obvious fact that the “Performance Rankings” of PossessionPoints.com are far different from the traditional opinion-based Power Rankings that you read about in many other places. For proof of this, you need to look no further than the number 1 spot on our Rankings, which is held by the Philadelphia Eagles for the second week in a row. How can this be when the Eagles have an uphill fight just to make the playoffs? Well, we would like to take a little time this week to explain how the Eagles can occupy this coveted spot.

At PossessionPoints.com, we color code a team’s Offensive, Defensive and Net performances (the difference between the Offensive and Defensive performances). We use Green to denote “good” performances; Yellow to symbolize “average” performances; and Red to signal “poor” performances. The colors change at specific values, and we correlate a winning percentage to each of these values. For instance a “Green” Offensive performance wins about 75% of the time (this is based on the data we have kept over the past 3 seasons.) A “Green” Defensive Performance wins over 85% of the time while a “Green” Net wins over 90% of the time. Our Performance Rankings (Relative Performance Measure – RPM) are based on the Net measure which as we say correlates over 90% of the time to winning in individual games.

So, how did a team that has only won 57% of their games wind up with an average Net that is Green? Looking at Philadelphia’s individual games is the easiest way to explain this. In their losses, the Eagles’ Offense and Defense took turns causing them to lose. The Eagles had three ‘Red’ Defensive performances which resulted in losses for all three of these games. A typical team will win 25% of the Red performances. The Eagles also had two Red Offensive performances and lost one of these games and tied one of these games. A typical team will win 15% of these Red Offensive performances. What is unique about the Eagles is that none of their poor Offensive and Defensive performances occurred in the same games. Compare this to the Giants who have had six Red Defensive performances and lost only three of these games. In the games they won, their Offense picked up the slack. In the three games the Giants lost, they recorded their only three Red Offensive performances of the year.

So, most “good” teams will on occasion have a bad game on both sides of the ball and lose those games. The Eagles have not shared that pattern. Their “bad” performances on Offense and Defense have occurred in different games causing them to pile up the losses. When they had a Red Offensive performance, their Defense was Green in the game they tied and Yellow in the game they lost. Statistically, both a Green and Yellow Defensive performance should have been able to overcome the Red Offense. The Eagles failed to do that.

In their three Red Defensive Performance games, the Eagles had two Green Offensive performances and one Yellow Offensive performance. Again, they lost all three of these games which other teams would have turned into wins.

We have spent a lot of time explaining the Eagles this week, so we will just quickly summarize the other top five teams on our Performance Chart: The Vikings, Ravens, Steelers and Giants round out the top 5.



On to the bottom 5. It is no surprise to find Cincinnati in our bottom 5 at number 30 since by our RPM measure they have had the toughest schedule in the league. Next week, we are going to talk about how each team’s strength of schedule has affected their performances this season.
The other 4 teams in our bottom 5 are the Rams, Lions, Seahawks and Raiders. These teams’ schedules have been no picnic either.

A final note, if the Eagles do manage to make the playoffs, the other teams in the NFL better take them seriously because they do have the capability to beat any team in the NFL if all their units show up to play.

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