Barnwell, “The NFL’s Cloudy Crystal Ball,” Grantland Aug 20, 2012

“Before we start, though, a quick acknowledgment about football statistics. For a variety of reasons, they are less meaningful and harbor less authority than their big brothers in baseball. Football statistics are about where Bill James was in 1986, just with additional computing power. There are still reams of data to be compiled, stunning concepts to be proven, and a billion arguments to be had. Even then, though, football has far fewer discrete events and games than baseball does. Our collective knowledge of football through numbers is going to improve, but it’s never going to catch up.

Do those weaknesses render football metrics irrelevant? Absolutely not. In fact, the metrics and concepts we’re going to highlight today exploit the fact that there’s a small sample of games by proving just how meaningless a great performance across a 16-game slate can be, especially when a team’s performance is reduced solely to the topic of wins.”