Two Saturdays ago, the Seattle Seahawks became the first team with a 7-9 record to appear in an NFL postseason game. Thanks to the league’s method of determining home-field advantage, the Seahawks hosted the New Orleans Saints in Seattle.

Thanks in part to Marshawn Lynch breaking off a Nathan Arizona-style run, the Seahawks engineered a massive upset of the defending Super Bowl champions. They surely also benefited, though, from the raucous Qwest Field crowd. The next week, the Seahawks traveled to Chicago, where they lost to the Bears and were thoroughly out-played through most of the game. The Bears were a better team than the Saints were a week prior, to be sure, but the Seahawks weren’t the same team without their 12th Man and, perhaps just as importantly, their subsequent 13th Through 63,336th Individuals.

We know that home-field, -court, and -ice advantage is real. Teams win more games at home. I wondered, though, whether we over-value or under-value such an advantage, so I nerded out and crunched some numbers.