NFL officials prepare for games each week similarly to how NFL teams game plan for weekly opponents. In this instance, officials study team matchups for games they are assigned to, along with league-wide tendencies.
An aspect of a play that can change officials' responsibilities is whether the play is a designed run or drop-back pass. Penalties such as defensive holding, pass interference and roughing the passer are only typically called when the quarterback drops back to pass. Pre-snap tendencies can also aid officials when it comes to their responsibilities on a given play.
As a way of assessing league-wide offensive tendencies, the plot below uses the NFL’s Next Gen Stats locational data to visualize pass rates based on running back alignment. Only plays with the quarterback in shotgun formation with exactly one running back are used. Additionally, only locations (0.5 x 0.5 square yards) with a minimum sample of 10 plays are provided.
When the running back is aligned alongside the quarterback, the vertical and horizontal position of the ball carrier is a strong signal of the play type. For example, when the running back is two yards behind the quarterback, teams only pass the ball around 20% of the time (shown in the red cells). Alternatively, when the running back and quarterback are at equal depths (70% pass rate), or if the running back is in front of the quarterback (85% pass rate), the likelihood of a pass play is higher.
Teams lining up in the pistol set, where the ball carrier lines up behind the quarterback, tend to run the ball as well, though that rate increases when the ball carrier is closer to the quarterback.
Location-based passing tendencies can vary from team to team. For example, when analyzing plays with a single running back located 5 to 7 yards behind the line of scrimmage, the league average pass rate is 44%. But in 238 plays in those formations, the Dallas Cowboys passed the ball 67% of the time, while the Houston Texans only passed it 25% of the time in 265 total plays.