A Look at Boise State's Efficiency from 2009

Since everybody else is getting into the act of looking at Boise State's stats from last year, I figured I might as well join the party. For the last couple of seasons, I've looked at Virginia Tech's offensive and defensive efficiency stats to see how well the Hokies did against what was expected of them against their opponents (2009: Offense | Defense).

This is a very dumbed-down take on what Football Outsiders and Rock M Nation do on a weekly basis. I've applied the same formula to Boise State's offense and defense. The Broncos put up big numbers against a relative weak schedule last season, but the stats tell us they still out-performed what was expected of them against those WAC defenses everyone likes to talk about. Meanwhile, on defense, they shut down just about everybody they faced.

Raw numbers after the jump.

Here's what we're doing. On offense, take the number of yards per play given up by the opposing defense for all of 2009 and multiply it by how many plays Boise State ran against them in their game. That gives you the total yards Boise State should have had against them. Then that number is compared to the Broncos' actual total yards in the game. Your baseline is 1.000, so anything above is good and anything below is bad. The opposite is true for the defense. Anything below 1.000 is good, above is bad.

Raw data is from CFBStats.com.

(OppYPP - Opponents' yards per play allowed in 2009 (rounded in chart, not rounded in equations); BSUPlay - Number of plays run by the Broncos in that game; ExpYds - Number of yards the Broncos should have gained in that game; BSUYds - The Broncos' actual output in that game; BSUEff - Boise State's efficiency for that game.)

Even against those lackluster WAC defenses, Boise State outperformed expectations in nine of 12 games. The big exception was against Oregon, when the Ducks held them to 47 yards fewer than they should have.

Basically, Boise State faced some bad defenses last year, but they still did a lot better than the typical team did against those bad defenses.

On to the defense.

(OppYPP - Opponent's' yards per play in 2009 (rounded in chart, not rounded in equations); BSUPlay - Number of plays run by the opponent in that game; ExpYds - Number of yards the opponent should have gained in that game; BSUYds - The opponent's actual output in that game; BSUEff - Opponent's efficiency for that game.)

Boise State's defense, which is regarded as underrated by a lot of people who are talking about this game, held its opponents below their expected yards in 10 of 12 games against FBS competition. Even Nevada, who seemingly ran roughshod over the Broncos, still should have done a lot better given 66 plays.

A lot has been made about Boise State's weak schedule. But against that schedule the Broncos took care of business and in most cases did it with impunity. They have an offense and defense that is not only very good, but according to these admittedly rudimentary numbers, is also very efficient. They perform well, even when judged against the relative weakness of their competition.

Virginia Tech put up equally good efficiency numbers (in ACC play) last season, 1.170 on offense and 0.859 on offense. I think we're in for a fantastic game on Labor Day.