SITE NEWS: We are moving all of our site and company news into a single blog for Sports-Reference.com. We'll tag all PFR content, so you can quickly and easily find the content you want.
Also, our existing PFR blog rss feed will be redirected to the new site's feed.
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For more from Chase and Jason, check out their work at Football Perspective and The Big Lead.
ShareThisSite Features: Approximate Value Leaderboards!
In a move that's admittedly long overdue, we've added Doug's Approximate Value metric to a variety of places throughout the site:
- Leaderboards: Single-Season, Career, Career (Active), Year-by-Year, Weighted Career, Weighted Career (Active), & Yearly League
- Player Pages: Stat tables, Similar Players, leaderboard appearances, weighted career AV listing
- Franchise Pages: Team listing, Season index, franchise career register
And as always, you can search for AV leaders using the PFR Play Index's Season Finder (example).
Also, we overhauled the main AV page to make it more user-friendly, added a sub-page for Doug's extended explanation of the method, and created a blog category for AV to make it easier to find past and future posts that feature the stat.
This entry was posted on Thursday, December 9th, 2010 at 12:07 pm and is filed under Announcements, Approximate Value, P-F-R News, Play Index, Site Features. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.
Can someone remind me what the difference is between career and weighted career. Does weighted career give peak performance extra credit or something?
Right, "career" is just the regular sum of a player's seasonal AV totals. But "weighted career" weights everything so that peak years have more importance. The formula for weighted career AV is:
100% of a player's best year + 95% of his 2nd-best year + 90% of his 3rd-best year + ...
And so on.
Christmas came early... thanks guys, this is an awesome addition.
Neil,
Some of the 2009 AV's are incorrect still which make those particular player's Weighted AVs and Career AVs incorrect.
I believe the '09 all-pro/pro bowl teams have been updated, so AV should be corrected when Doug re-runs everything after the season.
Ok. Thanks Neil.
On thing I did notice is that Brian Cushing still has AP 2nd team all Pro from last season. He lost his spot on the re-vote, due to his suspension, to James Harrison and Lance Briggs. They both tied in the revote and split an AP 2nd team all pro selection.
That seems to be the only correction that needs to be made.
Thanks, Johnny. I'll check if those were in the latest spreadsheet I submitted (and they just haven't been refreshed yet) or if I need to make a change and re-upload.
OK, that should be reflected the next time we update. Thanks again.
Neil-
I noticed on team pages, where the yearly AV leader is listed, ties are not indicated, and just one guy is listed. Is this deliberate, because of the frequency of ties? Just curious if you know about it and, if so, any changes were planned. Thanks.
(I posted this elsewhere on the site, but I think that this is the appropriate thread. Thank you for allowing me into your discussion.)
This is my first comment here. I've been interested in the statistical analysis of football (NFL) since I first discovered The Hidden Game of Football. As flawed as that wonderful work was, it still generated a lot of thinking on my part.
I am now trying to reproduce PFR's AV methodology in order to take a view on its usefulness (first rule of scientific method is that a model must be such as to be reproduced by other observers). I've created a spreadsheet and, as a starter, am trying to reproduce 2009 and some "test" QB's.
I have successfully reproduced the 2009 AV for Brady (16.7 vs. PFR Actual of 17), P. Manning (16.9 vs. Actual of 17), Rivers (18.9 vs. 19) and Roethlisberger (13.6 vs. 14), but I can't get what seems to be my properly functioning model to produce the same results as PFR for Drew Brees.
Can someone tell me where I am going wrong or whether PFR is wrong? I have taken the following inputs from PFR and made the listed calculations:
League 2009
Rushing TD's 429
Passing TD's 710
Field Goals Made 756
Field Goal Attempts 930
Total Turnovers 872
Interceptions thrown 525
Fumbles Lost 347
Punts 2451
Rushing Yards 59739
Passing Yards 111851
Total Yards 171590
Saints 2009
Rushing TD's 21
Passing TD's 34
Field Goals Made 22
Field Goal Attempts 28
Total Turnovers 28
Interceptions thrown 12
Fumbles Lost 16
Punts 58
Rushing Yards 2106
Passing Yards 4355
Total Yards 6461
Brees
Passing Yards 4388
Passing TD's 34
Pass Attempts 514
Interceptions thrown 10
Sacks 20
Sack Yards 35
I am using the following factors as given in the "AV Methodology" section:
OLine: .455
Rusher: .220
Rush/Total Yds Avg since 1970: .370
Passer Factor: .260
TD Multiplier: 20
INT Multiplier: 45
I end up with the following, using the formulas provided:
League Average
Offensive Points per Drive 1.90
Offense Points 100
Team Points for o-line 45.5
Team Points for skill positions 55.5
Team Points for Rushers 11.3
Team Points for Passers 11.2
Saints
Offensive Points per Drive 2.67
Offense Points 140.5
Team Points for o-line 63.9
Team Points for skill positions 76.6
Team Points for Rushers 14.9
Team Points for Passers 16.1
Brees Base Score 16.2
Bonus 1.4
Total 17.6
Actual Brees for 2009 per PFR: "16"
League
Adjusted Net Yards Per Pass Attempt 6.04
Pass TD Multiplier 20
INT Multiplier 45
Brees
Adjusted Net Yards Per Pass Attempt 8.82
Pass TD Multiplier 20
INT Multiplier 45
I appreciate the help. This model is getting some attention and, before I evaluate it, I want to be sure (a) that I know how it works and (b) that it works consistently on the web page.