Last week we covered our statistical adjustments for depth of passes with passing plus-minus and receiving plus-minus for the 2017 season. When we want to add context to what the receiver did with the ball in his hands, we use YAC+. You can see last year's study here. The following description of YAC+ is from the upcoming Football Outsiders Almanac 2018 (available in July), where every player with his own table will have his plus-minus and YAC+ listed for the past three seasons:
YAC+ is similar to plus-minus; it estimates how much YAC a receiver gained compared to what we would have expected from an average receiver catching passes of similar length in similar down-and-distance situations.