Week 7 Power Rankings


Calculated Power Rankings, Unit Strength, Strength of Schedule, and Estimated Final Record following week 7 of the NFL season.  I use an engineering method of iteratively solving for best fit to the data (scores) to create the ranks and related applications that corrects for opponents played.

To calculate the power rankings, I calculate strength factors for each unit of each team, what they are expected to score or give up to an average opponent, on offense and defense; which is equivalent to scoring offense or defense (NFL.com stat) but adjusted for the opposition played. The calculation is basically making each unit of each team a variable, and solving for each variable iteratively, what would most closely create the NFL season. (A really huge polynomial calculation with an approximate solution). The net difference between the factors is then considered team strength, the teams ranked by this for power. Basically it is assumed that neither offense nor defense is superior, the relationship of one to the other determines team quality.

Early in the season this was smoothed with a preseason projection, it takes several weeks for the data to “calm down” and give reasonable results, however I’ve completely dropped all preseason projections from the calculation, however I’ve added hot calculation.

To acknowledge the hot/cold factor of teams, I am running 2 versions of the calculation, from the beginning of the season, and the most recent 4 weeks. The recent calculation is then combined with the season long calculation at a 1:4 ratio, to tweak the results for hot and cold teams. It is also provided separately for information purposes. I expect this short term calculation to fluctuate wildly and over time highly diverge from the primary calculation, right now the only difference is the week 1 games.

The previous rank is in parenthesis, ranked by net expected scoring against an average opponent, recent calculation only rank in brackets (the main rankings should trend toward the bracket)

Week 7 Power Rankings:
1. New Orleans Saints (1) – 20.1 [1]
2. New England Patriots (2) – 15.8 [2]
3. Denver Broncos (5) – 13.0 [4]
4. Indianapolis Colts (4) – 11.9 [7]
5. Miami Dolphins (10) – 9.1 [5]
6. New York Jets (15) – 8.3 [16]
7. Arizona Cardinals (9) – 8.2 [3]
8. Baltimore Ravens (6) – 8.0 [15]
9. Cincinnati Bengals (16) – 7.9 [9]
10. Atlanta Falcons (3) – 7.8 [10]
11. Green Bay Packers (11) – 7.0 [6]
12. Minnesota Vikings (7) – 5.5 [12]
13. Dallas Cowboys (19) – 5.1 [8]
14. New York Giants (13) – 4.5 [13]
15. San Diego Chargers (18) – 4.3 [17]
16. Pittsburgh Steelers (17) – 3.7 [14]
17. Houston Texans (21) – 1.3 [11]
18. Seattle Seahawks (14) – 0.6 [18]
19. San Francisco 49ers (12) – 0.3 [19]
20. Chicago Bears (8) – -1.3 [22]
21. Philadelphia Eagles (20) – -1.6 [23]
22. Buffalo Bills (22) – -2.3 [21]
23. Cleveland Browns (24) – -8.5 [20]
24. Jacksonville Jaguars (23) – -10.0 [30]
25. Carolina Panthers (27) – -11.6 [25]
26. Kansas City Chiefs (25) – -11.6 [24]
27. Detroit Lions (26) – -11.8 [27]
28. Washington Redskins (29) – -13.7 [26]
29. Oakland Raiders (28) – -15.3 [29]
30. Tampa Bay Buccaneers (31) – -16.1 [28]
31. Tennessee Titans (30) – -16.9 [32]
32. St. Louis Rams (32) – -22.0 [31]

Miami left me scratching my head looking for errors. The matrix presentation of scores showed why the results are like that pretty easily, Miami has been the highest scoring team for 4 of 6 of their opponents, they lead the league at that. Performing away from the norm is rewarded with this means of modeling. We have a few flip floppers, teams who have fairly drastically different data results with only minor tweaks overall. Jets, Bengals, and 49ers fit in this category. They tend to be teams that were previously at a very different level (the Jets are a big example). Last year, Arizona was a flip flopper, oscillating between top 5 and bottom 10 almost weekly all season long.

Top 5 Offenses:
1. New Orleans Saints – 40.0 (ridiculous)
2. New England Patriots – 30.4
3. Miami Dolphins – 30.0
4. San Diego Chargers – 29.7
5. Minnesota Vikings – 28.7
Ranked by expected scoring against an average defense.

Top 5 Defenses:
1. Denver Broncos – 9.8
2. New York Jets – 13.1
3. New England Patriots – 14.6
4. Arizona Cardinals – 15.4
5. Indianapolis Colts – 15.5
Ranked by expected points scored against by an average offense.

5 Worst Units:
1. Washington Redskins Offense – 8.4
2. St. Louis Rams Offense – 9.3
3. Oakland Raiders Offense – 9.4
4. Tennessee Titans Defense – 30.9
5. St. Louis Rams Defense – 30.5
Ranked by the greatest negative deviation from the average opponent (21.5 ppg)

Who’s Hot:
1. Arizona Cardinals – 2.1
2. Miami Dolphins – 1.7
3. Houston Texans – 1.7
4. Dallas Cowboys – 1.1
5. Green Bay Packers – 1.0
Teams whose expected net scoring agaisnt an average opponent varies the greatest (positive) between the full season run, and the most recent 4 week run.

Who’s Not:
1. Tennessee Titans – -3.1
2. Jacksonville Jaguars – -2.7
3. Philadelphia Eagles – -1.5
4. Oakland Raiders – -1.1
5. San Francisco 49ers – -1.1
Teams whose expected net scoring agaisnt an average opponent varies the greatest (negative) between the full season run, and the most recent 4 week run.

As the season goes along, I expect the who’s hot/not lists to become much more interesting, to help ID teams with bad starts playing good ball, or vice versa.

I have another application done with my program, a strength of schedule calculation. I chose to use the power rankings as the data to create the calculation. The average weekly ranking of all opponents will be what is used to rank the teams. Two methods are tracked, what the opponent was ranked at the time of the game, and the most recent ranking of each opponent, taken to be the most accurate. Right now I’m only reporting data based off of the most recent ranking, though watching the other as well. I think this will give a little different picture than pure W-L as to schedule difficulty, to try to find a better way.

The number in parenthesis is the ranked difficulty of the future schedule. The number reported is the average power ranking rank of all opponents played thus far. Teams are ranked by the overall difficulty of schedule.

Strength of Schedule:
1. Carolina Panthers (1) – 20.7
2. Tampa Bay Buccaneers (2) – 17.9
3. Buffalo Bills (6) – 13.1
4. New England Patriots (3) – 15.7
5. Miami Dolphins (21) – 9.7
6. New York Jets (8) – 15.3
7. Oakland Raiders (12) – 14.6
8. Baltimore Ravens (13) – 14.5
9. Tennessee Titans (22) – 11.5
10. Detroit Lions (14) – 14.7
11. Houston Texans (7) – 17.9
12. Cleveland Browns (27) – 11.6
13. Pittsburgh Steelers (5) – 19.6
14. Cincinnati Bengals (24) – 14.0
15. Atlanta Falcons (23) – 14.0
16. St. Louis Rams (16) – 16.6
17. Chicago Bears (20) – 15.2
18. Jacksonville Jaguars (11) – 18.2
19. Indianapolis Colts (9) – 19.5
20. Kansas City Chiefs (15) – 18.3
21. Denver Broncos (26) – 15.2
22. New York Giants (17) – 19.1
23. San Diego Chargers (29) – 14.5
24. Minnesota Vikings (18) – 19.4
25. Philadelphia Eagles (10) – 23.2
26. San Francisco 49ers (28) – 16.0
27. Green Bay Packers (19) – 20.5
28. Washington Redskins (4) – 25.0
29. Dallas Cowboys (25) – 18.0
30. New Orleans Saints (31) – 15.8
31. Seattle Seahawks (30) – 17.7
32. Arizona Cardinals (32) – 16.0

I also added another application that uses the schedule programming, used to create the strength of schedule, current records, and the latest power ranking run, to determine an estimate for final records.

Estimated Final Record:
New Orleans Saints – 15-1
Denver Broncos – 14-2
New England Patriots – 13-3
Cincinnati Bengals – 12-4
Indianapolis Colts – 12-4
Arizona Cardinals – 12-4
Minnesota Vikings – 12-4
New York Giants – 11-5
Green Bay Packers – 11-5
Atlanta Falcons – 11-5
New York Jets – 10-6
Pittsburgh Steelers – 10-6
Dallas Cowboys – 10-6
Miami Dolphins – 10-6
San Diego Chargers – 10-6
Baltimore Ravens – 10-6
San Francisco 49ers – 9-7
Houston Texans – 8-8
Chicago Bears – 8-8
Philadelphia Eagles – 8-8
Seattle Seahawks – 7-9
Buffalo Bills – 7-9
Jacksonville Jaguars – 5-11
Cleveland Browns – 4-12
Kansas City Chiefs – 3-13
Oakland Raiders – 3-13
Detroit Lions – 3-13
Washington Redskins – 3-13
Carolina Panthers – 2-14
Tennessee Titans – 1-15
St. Louis Rams – 1-15
Tampa Bay Buccaneers – 0-16

Estimated record uses the schedule matrix and power rankings, and assumes that the team higher in the current rankings will beat the team lower in the current rankings a certain % of the time, throughout the remainder of the season. These projections will change weekly with the power rankings and actual results.

The code captures the net expected points for each team, and compare them (basically equivalent to the line for a game, what the expected outcome of the game is), for every game remaining during the season, using the most recent data run.

If a team is favored by 14+ points, I assumed that they win 100% of the time.
If a team is favored between 7 and 14 points, I assumed that they win 80% of the time.
If a teams is favored between 0 and 7 points, I assumed that they win 60% of the time.
If a team is not favored between 0 and 7 points, I assumed that they win 40% of the time.
If a team is not favored between 7 and 14 points, I assumed that they win 20% of the time.

This is then used to compute wins and rounded to the nearest integer. (plus a correction made so that there are 256 game winners).

Using the above, to track the playoff hunt (I have no odds, but this is how I calculate it to play out currently, the above results sorted differently):

The Playoff Hunt:
(** = HFA (#1 seed), * = Bye (#2 seed))

AFC Divisions:
**Denver Broncos – 14-2
*New England Patriots – 13-3
Cincinnati Bengals – 12-4
Indianapolis Colts – 12-4

AFC Wildcard:
New York Jets – 10-6
Pittsburgh Steelers – 10-6
Miami Dolphins – 10-6
San Diego Chargers – 10-6
Baltimore Ravens – 10-6

NFC Divisions:
**New Orleans Saints – 15-1
Arizona Cardinals – 12-4
* Minnesota Vikings – 12-4
New York Giants – 11-5

NFC Wildcard:
Green Bay Packers – 11-5
Atlanta Falcons – 11-5
Dallas Cowboys – 10-6
San Francisco 49ers – 9-7

Power Ranking Performance:
Week 1 record – 14-2
Week 2 record – 11-5
Week 3 record – 12-4
Week 4 record – 11-3
Week 5 record – 7-7
Week 6 record – 9-5
Week 7 record – 9-4
Total – 73-30
Missed Last Week – Mn-Pit, SF-Hou, Chi-Cin, Atl-Dal

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