So your Philadelphia Eagles are suffering from a severe infection: home losses. It started innocently enough, with a 26-23 overtime loss to the Detroit Lions. But that loss begot another loss, and then another, and yet another. Nine losses later the infection lingers. But there is a cure, perhaps a panacea even. Does your team have a weak defense? An inconsistent offense? A fever? Runny nose? Hacking cough? Diarrhea? No worries. I present to you Eli Manning and the New York Football Giants, the appropriate antibiotic. Take four quarters worth and rest for a week.
The last time the Eagles won at home was September 30, 2012 against the Giants when Alex Henery kicked a 26 yard field goal with less than two minutes remaining, and Lawrence Tynes missed a 54 yarder with 10 seconds left to seal the 19-17 win for the Birds. If history repeats itself (and with the Giants it has), then it’s time to have some more fun at the Giants’ expense.
Last week’s simulation successfully (but barely) projected a Dallas Cowboys victory. Similarly, this week’s simulation barely projects an Eagles’ victory. After 10,000 simulation runs, the Eagles win a small majority of the time (53%) by an average of 1.6 points. If turnovers are equal for the two teams, the Eagles increase their chances of winning (57.5%) by an average of 1.9 points. Turnovers, as usual, are the great equalizer. If the Eagles have one more giveaway than the Giants, they lose 66% of the time by an average score of 21 to 19.
However, if Michael Vick can operate the Eagles’ offense at or above their season efficiency average (69%), and the Eagles’ defense can hold Eli Manning and the Giants’ offense at or below their season average (64%), their odds are even more favorable, winning 65% of the simulated games by an average of five points. Doing this also buys them some room with turnovers; even with one more giveaway than the Giants, the Eagles are still projected to win.
The Eagles’ defense has improved, Michael Vick has returned, and Eli Manning has been Eli Manning(face). If Chip Kelly wants to break this home losing streak, then this is the game to do it. Interact with the graphic to see more...
Note: NFL simulations are far from an exact science. They attempt to mathematically project the future based on history and past performance, but they can’t account for everything. A stiff breeze, a tipped ball, a freak injury, a rolling fog bank, an ol’ coach’s return, or simply a change in player attitude can alter results in a large way. Instead, simulations give us a blurry view of a series of possibilities among an infinite number of potential realities. But they’re fun. If you believe in parallel or multiple universes, then one of these simulated results could possibly occur.
The simulation is based on my home field advantage (HFA) research, which shows how there have been small but distinct and different offensive efficiency behaviors between home teams and away teams in the NFL. And not surprisingly, turnovers play a large role in equalizing the playing field. Offensive performances throughout the season were entered into a logistic regression formula born from the HFA research, and randomized according to standard error values and turnover differential.
Step 1: Calculate Offensive Efficiency (OE). I used Chip Kelly’s definition for this:
(Rushes + Completions) / (Total Off Plays + Offensive Penalties)
If you check out the HFA research, there’s a really strong correlation between offensive efficiency and team success.
Step 2: Calculate Win Probabilities using the logistic regression formula that correlated OE to team success. Here’s the formula:
Win Probability = 1 / (1 + e^-((A*OE+error value) + (B*Turnover Diff + error value) + C)), where A, B, and C are constants.
Step 3: Convert the results from Step 2 into points using a linear formula:
Points = A*(Win Probability for Eagles) + B*(Win probability for Opponent) + C, where A, B, and C are constants.