If football were a brand new invention, and we had to decide how to credit the various amounts of yards gained to various players, how would we do it? If I said, "There's this kind of play called a pass, in which a thrower passes the ball to a another player who then runs with it as far as he can. I say we credit all the yards run by the receiver to the thrower." You'd say I was nuts.
I'd say, "Well, it takes a special kind of talent for a passer to get a lot of yardage after the catch (YAC). I won't be able to prove it, in fact, I won't have any evidence for that statement at all, but I still think our primary measure of a passer should include all those yards." I'd be laughed at.
Here are the QBs from 2007 who led the league in percent of their passing yardage as YAC: Croyle, Testaverde, Greise, Harrington, Favre, McCown, Losman, and Lemon. The 2006 list includes Brunell, Carr, Favre, (Rob) Johnson, and (Alex) Smith. There's isn't a single guy on that list who we can call a legitimate starter.
The 2008 season's list of leaders in %YAC include Cassel, O'Sullivan, Campbell, Favre (again), Losman, and Wallace. But Matt Cassel is good, right? Maybe not. Keep in mind how good the team around him was. He was handed the keys to a Ferrari. If a QB racks up his passing yards with YAC, he's either throwing lots of short check-downs and screens, or he has spectacular receivers--or both. Neither is necessarily an indication of a particularly skilled passer.
If we throw away all the YAC and look underneath, what do we have left? I call it Air Yards (AY). It's the distance forward of the line of scrimmage a pass travels. Although it's not a perfect measure of a passer, I think it makes a lot more sense than crediting Donovan McNabb with 71 yards and a touchdown for a 1-yard screen pass to Brian Westbrook.
I agree with this. It's just one measure, and of course accuracy does help lead to more YAC and even screen passes take some athleticism and dexterity to pull off, but the analysis here indicates that we should not give QBs too much credit.
The other reason I like it is because it heightens accountability for yards after catch yards for receivers. If receiver X gets a lot of YAC and receiver Y doesn't, it might be a function of the offense they play in or the types of routes they run, but you nevertheless get a way to compare receivers and put the burden on them: either he's getting yards after the catch or he isn't, and the team should play a guy who gets them. Now, part of Brian's analysis here seems to indicate that it is QBs who drive this as much as anything else -- if a QB can't complete it downfield he'll inflate YAC all around with dump-offs. But, as I said, it's a fascinating statistic as a way to unpack yards per attempt, which is still the best overall metric of a passing offense.
2. Assorted Links
- Dan Shanoff tells us what was hot or not in 2008.
- Utah 's Attorney General is considering some kind of anti-trust challenge to the BCS. The Wall Street Journal Law Blog explains.
- Florida won the BCS? Not so, says some computers. Texas beat USC, 505 victories to 496.
- Pro Football Reference Blog with an interesting proposal for NFL overtime.
3. Favicon. Smart Football now has a "favicon." We're doing it real big over here.