All of this talk about deflating footballs begs a natural question: What are the differences in performance in Tom Brady’s performance at home (where the Patriots are alleged to have tampered with the footballs) and on the road (where, based on the existing accusations, they would not have tampered with the balls)?
The following table is a list of all the quarterbacks in the last two seasons who have attempted at least 200 passes at home and on the road. The numbers show are the difference between home and road performance. In other words, a positive number means a higher number at home. Below are the results:
In the last 2 years, Aaron Rodgers has shown the greatest improvement at home relative to away games. Rodgers ranks first in interception percentage drop, first in increase in touchdown percentage, second in increase in yards per attempt (Brandon Weeden is first) and first by a landslide in QB Rating. Tom Brady is 10th in improvement at home in QB rating, leagues behind Rodgers amazing 37.9 QB Rating jump in home games.
What if we expand the sample to go back to the 2006 rule change where quarterbacks from each team could control the ball? How does Brady look then? (Min 500 attempts home and away to qualify for this sample.)
Brady has actually been quite poor over the long haul at home, at least from a basic statistical perspective. Brady is well below average in these areas, showing a pretty significant road bias (not home) in performance. The average for these 45 qualifying quarterbacks was an improvement of 3.9 QB Rating points at home, 0.2 more yards per attempt at home, a 0.4% bump in TD% and 0.2% drop in INT%. Brady does throw fewer interceptions at home per pass, but his other numbers actually trend in the opposite direction and are better on the road. His QB Rating is a shade better at home, but again, that indicates abnormally strong play on the road relative to the rest of the quarterbacks in the league.