Using Pythagorean Wins to Pound the NFL Odds

Do you remember the Pythagorean theorem? This little bit of geometry is so famous, they’ve written poems and made movies about it. Uganda even minted a triangle-shaped coin in 2000 featuring Pythagoras on the back. Vending machines seem to have trouble with it, though.

Now it’s time to mint some more money using Pythagorean expectation. This concept was created by advanced baseball stat pioneer Bill James, who felt that you could more accurately gauge a team’s performance by looking at runs scored and runs allowed, rather than wins and losses. James turned out to be a visionary; his work has been adopted by analysts across the sports world – including people who are serious about betting on the NFL.

Anyone with Web access and half a brain can do it. The Football Outsiders website crunches all the numbers and produces what it calls Pythagorean Wins, based on points scored and points allowed. This information is incredibly valuable for NFL betting, and it’s free to use.

So how do you use it to make money? Let’s review: the idea when you bet on the NFL is to find situations where there’s a difference between the “true” value of a team and its perceived value in the NFL betting marketplace. You then exploit this market inefficiency by betting on the undervalued teams and fading the overvalued teams.

One very simple way to find these situations is to compare a team’s Pythagorean Wins to its actual wins. The larger the difference, the greater the market inefficiency for you to exploit. The 2011 Kansas City Chiefs, for example, went 7-9 SU (9-7 ATS) despite posting just 4.1 Pythagorean Wins. The 2012 Chiefs cratered to 2-14 SU and 5-11 ATS.

It’s not a foolproof method, mind you. There’s no such thing in NFL betting or anywhere else. The 2012 Philadelphia Eagles looked like worthy “follow” candidates after going 8-8 SU and ATS in 2011 despite posting 9.8 Pythagorean Wins. However, the 2012 Eagles were ruined by injuries and curious personnel decisions, finishing 4-12 SU and 3-12-1 ATS. Football happens.

Instead of using Pythagorean expectation in a vacuum, you should treat it as one very useful tool in your NFL betting toolbox. For example, we can start by identifying the teams from 2012 with a difference of at least one between their Pythagorean Wins (PW) and actual wins:

Follow Candidates:

Detroit Lions (4-12 SU, 6.4 PW)
Seattle Seahawks (11-5 SU, 12.5 PW)
Jacksonville Jaguars (2-14 SU, 3.3 PW)
New York Giants (9-7 SU, 10.2 PW)
New Orleans Saints (7-9 SU, 8.2 PW)
Cleveland Browns (5-11 SU, 6.1 PW)
San Diego Chargers (7-9 SU, 8.0 PW)

Fade Candidates:

Indianapolis Colts (11-5 SU, 7.2 PW)
Atlanta Falcons (13-3 SU, 11.2 PW)
Houston Texans (12-4 SU, 10.2 PW)
Tennessee Titans (6-10 SU, 4.6 PW)
Minnesota Vikings (10-6 SU, 8.8 PW)

Now we can narrow down our search and pick out the most promising NFL betting situations. The Lions appear poised for a rebound after an injury-plagued 2012 campaign; the 2012 Colts defied the NFL odds in support of cancer-stricken head coach Chuck Pagano, converting over 49% of their third-down opportunities at home. Regression to the mean is likely for both clubs.