The widely held and devoutly believed idea that a big play can change the momentum of a game is, in a word, bunk. So say a trio of MIT stats geeks with a decade of data to back them up.
Aaron Johnson, Alex Stimpson, and Torin Clark analyzed 473,621 plays run during the 2,931 NFL games played between 2000 and 2010 simply to determine whether big plays change the momentum of a game, motivating teams to perform better in subsequent drives. The results, presented in Turning the Tide: Big Plays and Psychological Momentum in the NFL (.pdf), found no evidence that a big defensive play has any effect on offensive performance later in the game.
That flies in the face of all that sports writers and armchair quarterbacks will tell you. Like many football fans, Johnson and his friends believed the conventional wisdom, but being engineers, they’re skeptical of everything until they’ve seen the data. So they decided to test it.
They gleaned stats from ArmchairAnalysis.com to examine 69,330 drives, which they divided into two categories: those that started after a big defensive play — an interception, fumble recovery, fourth-down stop, safety, or blocked kick — and those that did not.