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tiptap
09-07-2005, 09:30 AM
http://www.footballoutsiders.com/ramblings_print.php?p=2854&cat=3

...Explanation of Tables

Division: How often this team won division after simulating season 1,500 times.
Playoffs: How often this team made the playoffs after simulating season 1,500 times.
Mean Wins: Average wins for team based on DVOA projections and schedule strength.
Std Dev: This number represents how predictible the team is for 2005, according to the projection system. The lower the number, the more stable the projection. Jacksonville is the lowest team at 61. Arizona is the highest team at 115. (For math geeks, this is standard deviation of wins divided by mean wins, times 100. Arizona’s standard deviation was actually higher than its mean wins.)
Adjusted Offense: Projected level of offense, separated from defense, special teams, schedule, and luck, along with rank among the 32 teams.
Adjusted Defense: Same for defense.
Adjusted Special Teams: Same for special teams.
Total: Theoretically, point spread for this team if it played a perfectly average team on a neutral field, with rank among the 32 teams.
Schedule: Average DVOA of all 16 opponents, without considering home field. Ranked from hardest schedule (1: San Diego, 7.8%) to the easiest schedule (32: Seattle, -5.7%)....

Team_______Division_______Playoffs_______Mean_____Std.Dev _____ADJ.OFFENSE RANK _____ADJ.DEFENSE RANK__ADJ.SPECIAL/RANK_____TOTAL/RANK____ SCHED/RANK
KC __________39% __________54% ________9.5 _____64 _____________25.9_____3 _________22.2 ______17 ______0.3 _____11 ________4.0 ________5 ______5.0% ___4
DEN__________31%__________47% ________9.3 _____71_____________25.9_____4_________21.5 ______10 _________-0.2 ___23_________4.1___4______4.5%___7
SD__________20%__________29%_________7.8 _____76_____________24.7_____6_________23.5 ______28 _________-0.4 ___30_________0.8___15______7.8%___1
OAK_________11%__________19% ________6.8 _____64_____________22.6_____13_________24.2 ______31 _________-0.3 ___25_________-1.9___22______5.7%___3

The system really likes Kansas City, which was the best team in DVOA in 2003 and tenth last year despite a losing record. However, the team projection system doesn’t yet include some kind of team age variable, which is why the individual projections for all the Chiefs in Pro Football Prospectus add up to something a lot lower than this projection of team offense. That’s a problem that I will need to fix in 2006. No, I’m not sure why Denver comes out with a lower chance of winning the division and fewer mean wins despite its average opponent being slightly easier. Could this be related to Jacksonville’s low standard deviation? They are on Denver’s schedule and not Kansas City’s schedule. Or perhaps it is just a random quirk in the simulation we ran, and the two teams would have been tied if we ran the simulation another 1,500 times.

San Diego has the hardest schedule in the entire league and the system thinks the defense will fall apart again, even though the offense stays strong. . . .

Team_______Division_______Playoffs_______Mean_____Std.Dev _____ADJ.OFFENSE RANK _____ADJ.DEFENSE RANK__ADJ.SPECIAL RANK_____TOTAL/RANK____ SCHED/RANK
NE__________39%__________56% ________9.7 _____69_____________26.9_____2_________21.5 ______11 _________0.2 ___14_________5.6___2______4.9%___5
BUF_________29%__________42% ________8.7 _____93_____________20.0_____23_________17.4 ______3 _________1.1 ___1_________3.7___6______4.5%___8
NYJ_________27%__________45% ________8.7 _____83_____________24.6_____7_________22.3 ______18 _________0.3 ___10_________2.7___10______4.6%___6
MIA__________5%__________8% ________5.6 _____78_____________17.4_____29_________21.8 ______15 _________0.6 ___5_________-3.7___28______5.9%___2

There’s nothing too shocking about the projections for our first division, the AFC East, except perhaps that the Miami defense only projects to be average. New England comes out the best team, but not by as much as last year, and standard deviation says that Buffalo is the hardest team to project accurately. You might be surprised that New York’s offense is so high and its defense so low if you don’t either a) own a copy of Pro Football Prospectus or b) read our website regularly. It’s one of those subjects that gets beaten to death around here. According to average DVOA of opponent, four of the eight hardest schedules in the NFL are in this division, and the other four are in the AFC West. Of course, those two divisions play each other this year, plus the AFC East plays the NFC South which is probably the best division in the other conference (especially if we are wrong about Atlanta).

htismaqe
09-07-2005, 09:54 AM
San Diego has the hardest schedule in the NFL, Oakland is #3, we're #4, and Denver is #7.

OUCH.

carlos3652
09-07-2005, 10:02 AM
Hmmm...

San Diego
Miami
Oakland
KC
NE
Jets
Denver
Buffulo

8 Hardest Schedules come from these 2 AFC divisions and my guess is because they play vs each other...

cdcox
09-07-2005, 10:18 AM
So, is this your work or something that you are linking to? Regardless it is very impressive at first glance. You might be aware of the playoff prediction work I've posted here since the days of the Star board. Unlike this work it is based only on the outcomes of games already played in a given season, so it is only applicable after each team plays 4 -8 games. I'm going to be making available the software for these predictions this year. I'll really dig into the math behind this later. :thumb:

StcChief
09-07-2005, 10:23 AM
Cool. Looking forward to your work.

DanT
09-07-2005, 12:07 PM
Thanks for the link, tiptap!

tiptap
09-07-2005, 05:47 PM
So, is this your work or something that you are linking to? Regardless it is very impressive at first glance. You might be aware of the playoff prediction work I've posted here since the days of the Star board. Unlike this work it is based only on the outcomes of games already played in a given season, so it is only applicable after each team plays 4 -8 games. I'm going to be making available the software for these predictions this year. I'll really dig into the math behind this later. :thumb:

Three years ago I also started calculating statistics based upon pts/drive, TOP and other things. I was looking to use the methods the Oakland A's used in baseball (with 16 and not 160 games, football is more variable against expectation) and trying to translate that to football. And I stumbled upon the http://www.footballoutsiders.com/ site. They were about a year ahead of me. They also had the programming to obtain the NFL's official statistics on direction and success of plays that I didn't. So I've been using their information ever since. I have a real job, it is technically related but I just like to see numbers give some objectivity to my thoughts about my team.

Yes, I will be glad to see your prediction later on in the season.

Halfcan
09-07-2005, 06:05 PM
I don't know what all those graphs mean, but if you pick the Chiefs to win, I agree.