Imagine that football were just invented and we had to figure out how to credit passers with all the yards they generate, and I said let's include all the yards that the receiver runs after the catch. I'd be laughed out of the room. But that's the convention we've been handed.
It's not that QBs shouldn't be credited at all, because if a pass isn't completed there can be no yards after catch at all. And the argument that a very accurate QB that can hit a receiver in stride or lead him to open space to create YAC can't be ignored. Scheme matters too. But it's evident that some QBs feast on the YAC-gaining abilities of their receivers much more than others, distorting their overall stats.
I came up with Air Yards a few years ago as a method to compare passers with their receiver's YAC removed. Air Yards is simply the complement of YAC. It's the yardage a pass travels through the air forward of the line of scrimmage. AY is a unique and interesting way to view QB performance, but it's not perfect.
A QB would be penalized for completing a short screen that's caught a yard to two behind the line of scrimmage. But those plays are few and far between, and I don't lose any sleep worrying about them. We should also keep in mind that a QB's performance is never just his own. But AY might be an inch closer to isolating the individual QB's contribution than if we look at total passing yards alone.
Here are the leaders in AY for the 2011 regular season. The table is sorted by default according to Air Yards per Attempt (AirYPA), but you can re-sort the table by clicking on the column headers.
Get the rest of this article over at Advanced NFL Stats.