The folks at Football Outsiders put together their weekly team efficiency ratings to break down the NFL through eleven weeks of the 2011 season. While most power rankings are entirely subjective, Football Outsiders attempts to come up with an objective rating system for the league. They use Defense-adjusted Value Over Average (DVOA), which breaks down every play from the season and compares a team's performance to a league baseline based on situation in order to determine value over average.
As things currently sit, the Houston Texans are sitting at number one coming out of their bye week. DVOA does not factor in future performances based on injuries, so Matt Schaub's injury has not been factored in. Week 12 will see the return of Matt Leinart, so we'll see how it impacts them in the coming weeks.
The 49ers climbed from No. 5 to No. 4 as they continue to hover in the same area week in and week out. They rank second in special teams and third in defense, but their 19th ranked offense is what brings them down a notch. This week they face the Baltimore Ravens who are rated No. 9 in DVOA. The Ravens have the number one ranked defense, which helps make up for their No. 20 offensive unit and No. 29 special teams unit.
The Oakland Raiders hung steady at No. 18. They defeated the Minnesota Vikings but it was an up and down affair. They never really lost control of the game, but they let the Vikings hang around a bit. The Raiders host the No. 6 ranked Chicago Bears this weekend. The Bears have the number one special teams unit, sixth-ranked defense and 22nd-ranked offense. They have lost Jay Cutler indefinitely so it will be interesting to see how it impacts their offense.