Teamwise, Yards Per Pass Attempt Differential is my favorite. It's the so-called Killer Stat developed by the late Bud Goode. The new arrogant jerks like Aaron Schatz try to denounce it but for betting purposes I can tell you YPPA Differential is far superior to anything they have come up with. I've run countless Monte Carlo simulations. I think I mentioned about a month ago that Carolina was the most underrated team in the league. They had a very good YPPA Differential but a poor record. The Panthers logically rebounded to the mean by winning and covering their last four games.
Passer Rating Differential is another one. I remain more loyal to YPPA Differential simply because I've used it longer and know more about it. Last year the guys who tout Passer Rating Differential at coldhardfootballfacts.com got extremely cocky and basically announced that the Giants had no chance against the Packers, or in the playoffs period. I emailed them to be careful. This is a strange era. The regular season results still adhere to the old statistical and situational trends but the playoffs are more flimsy. Frankly, the results are weird and often unexplainable. I'm glad my simple system still works, taking any team with at least a half yard edge in YPPA Differential over its opponent. I have all four favorites this week -- Green Bay, Houston, Seattle, Baltimore. The Packers have the largest edge while Houston barely qualifies as exactly a half yard above the Bengals.
BTW, New England is surprisingly poor in the differential stats this year. In fact, barely above average.
Yards Per Attempt is the long term standard for quarterbacks. It will never lead you too far astray. The teams that gave big money and extended contracts to buttfumble and Fitzpatrick obviously didn't pay attention. Very infrequently there's a puzzling example like Tony Romo. He's in the top 6 or 8 all time in yards per attempt but obviously his results in big games don't align with that. When you hears fans belittle Romo but coaches and league analysts praise him or allow benefit of a doubt, it's because the NFL types are very much aware of Romo's excellence in getting the ball downfield.