When fans of opposing teams get into arguments regarding which team is superior, often the fight moves to stats to prove without a reasonable doubt that Team X is clearly better than Team Y (That is if the argument ever moves away from name calling or probation smack). When fantasy sports junkies look to find that up-and-coming Running Back that no one else is considering to boost their team, they turn to stats. When Owners and GM’s of poor professional teams look to find a competitive advantage against their rich counterparts, they look for stats that others don’t know the true value of. Statistics are all around us as sports fans and are readily available for consumption, but are the numbers we receive from the countless sources reliable or even meaningful? Are numbers like points per game, turnovers per game, or yards per game truly worthwhile in determining how good a team is, or do they merely tell us how a team plays? To get this discussion started I went back and investigated the most important factors in winning college football games from my most recent articles and compared those to stats like passing yards per game to see which ones were more meaningful in determining winners.
The below chart contains data from the 2007 season onward and shows the correlations to winning percentage of various efficiency stats like Passing Yards per Attempt compared to the traditionally shown stats like Passing Yards per Game. Remember here that the closer the number is to 1 or -1 the higher the correlation.
The first striking thing is how different the correlations are from one another, for instance an efficient passing game is one of the most relevant factors in advanced stats but its basic sibling, Pass Yards per Game, is largely irrelevant when it comes to winning games. Another place where the relative importance is largely different is pass defense, advanced stats say stopping opponents from passing is critically important while its simple cousin says stopping the pass is highly irrelevant. One category stayed similar to its advanced counterpart, Rush Yards per Game, so should this lead us to believe that efficient passing on both sides of the ball is irrelevant or critical to success?
To understand this predicament further I’ll let my good buddy Mark Twain have a word on the subject matter. “There are three kinds of lies: lies, damned lies and statistics.” Thanks Mark! My interpretation of his underlying theme (perhaps oversimplified) in that statement is be careful of the numbers you believe as they can be easily manipulated. So, should we believe the advanced way of thinking or the long held belief of traditional stats like Yards per Game? We should accept the advanced way as it takes numerous factors into account and puts them in one simple stat. Take the difference in passing stats for instance, Pass Yards per Attempt takes into consideration multiple things like incompletions, yards gained, and pass attempts whereas raw pass yards per game just takes into account what its name implies. There’s such a low correlation with winning in that stat because college football, as I proved yesterday, is a predominant running game, so naturally pass yards per game wont consider that. If a team gives up a low amount of total yards through the air it doesn’t necessarily mean they have a good pass defense, it could mean that their opponents rarely pass. The high correlation to Rush Yards per Game is significant to me for the previously stated reason that college football, as a whole, is a run first league. Since teams run at a high rate, naturally teams who stop their opponent should be more successful. So when interpreting a stat like Pass Yards per Game, just know that you’re not getting very good information because it takes little else into consideration.
So, if stats like Yards per Attempt are readily available why is it that we don’t often see them on a TV broadcast? I think the simple answers are that the audience doesn’t demand it and it’s convenient for the respective network to put in a simple number. A wide portion of the TV audience has little interest in Yards per Attempt because they want something quick and easy to satisfy their knowledge. Yard per Game stats give convenience but they don’t give good information. Yard per Attempt stats and other similar advanced numbers tell a much more compelling story and are simple to understand when an explanation is given. While not always the most convenient, it would be beneficial for the sports public to use more meaningful numbers in their evaluations so a more concrete truth can be reached.