Who are the Most Over and Under Paid Defensive Staffs in College Football?

Last week, USA Today released their annual data collection of assistant coaches salaries. As is want to happen, much weeping and gnashing of teeth abounded from fans griping about how much coaches are paid in relation to performance, or lack thereof. It's easy to look at the numbers and jump to radical conclusions. Most will be generally aware of their own staff, but perhaps not how others around the country stand.

Perhaps of my own personal interest, I wanted to see if we could draw any correlations between staff pay and performance, or, more precisely, see if the most over and under paid staffs in college football could be easily pinpointed. Thus, here we are.

The Strategy

Pretty simple. First, I pulled all the coaching salaries and broke them out in simple groupings by responsibility, purely offensive and defensive, and team. Any coach labeled with any responsibility in coaching a position on a particular side of the ball would be aggregated in the total staff pay total. Special Teams coordinators that also coach LBs or TEs are counted. As are all coordinators, regardless if they own positional responsibility. From their, I summed their salaries to get total staff pay.

Next, I needed a metric to quantify performance. I opted to pull S&P+, as its the most comprehensive stat readily available. If you aren't familiar with S&P+, here's a quick summary:

The S&P+ Ratings are a college football ratings system derived from the play-by-play data of all 800+ of a season's FBS college football games (and 140,000+ plays). There are three key components to the S&P+:

• Success Rate: A common Football Outsiders tool used to measure efficiency by determining whether every play of a given game was successful or not. The terms of success in college football: 50 percent of necessary yardage on first down, 70 percent on second down, and 100 percent on third and fourth down.
• IsoPPP: An explosiveness measure derived from determining the equivalent point value of every yard line (based on the expected number of points an offense could expect to score from that yard line) and, therefore, every play of a given game. NOTE: IsoPPP is in use for the first time in 2014. It looks at only the per-play value of a team's successful plays (as defined by the Success Rate definition above); its goal is to separate altogether the efficiency component from the explosiveness component. This results in a new equation below. Success Rate now accounts for 80% of S&P below, while IsoPPP accounts for just 20%. For more information about IsoPPP, click here.
• Drive Efficiency: As of February 2013, S&P+ also includes a drive-based aspect based on the field position a team creates and its average success at scoring the points expected based on that field position. It is factored in after seven weeks.
• Opponent adjustments: Success Rate and PPP combine to form S&P, an OPS-like measure for football. Then each team's S&P output for a given category (Rushing/Passing on either Standard Downs or Passing Downs) is compared to the expected output based upon their opponents and their opponents' opponents. This is a schedule-based adjustment designed to reward tougher schedules and punish weaker ones.

From there, it was just mapping the data on a scatter plot. The data is neat to see, but it also needs to be grounded. So I took the median of each collection of data, in effort to see what average pay and average performance would be. I used median rather than mean, because I thought the exceptionally high coordinator salaries would skew a true "average" salary.

Several teams could not be tabulated, due to being private schools that do not disclose the pay of their coaching staffs:

Boston College, Baylor, BYU, Duke, Hawaii, Miami, Navy, Northwestern, Notre Dame, Pittsburgh, Penn State, Stanford, Syracuse, TCU, Temple, Tulane, USC, Vanderbilt, Wake Forest.

The Charts

Here's an interactive chart. Notice the median values, which help make this more informative.

If you hover over a data point, you can see which team is which point. The chart isn't perfect, but it gives us some visual. Anything around or over that 100 line on the y-axis is "average", or better, performance, while anything past the $1,000,000 mark on the x-axis is paying above average. Here's another view of the same data, this time with a trendline, so you can see how many data points appear above and below the general tendency.

h/t to my buddy Logan Leger (follow him on Twitter @lleger) for help with the second chart.

This chart isn't interactive, so it's nice to see the data points, though we can't be sure which is which without consulting a chart.

UPDATE:

Dr. Awesome hooked me up with a sweet interactive chart:

Here's a full table of the data, so you can more easily review the values and performance:

What Does It Mean?

There's too many variables here to illustrate a direct causation. Naturally big programs can and will pay more. They are also typically the benefactors of working with better talent, which should mean better performance. This also doesn't account for early NFL departures, injuries, suspensions and the whole lot of things that can sink a unit's performance other than "bad coaching." Still, there's a pretty clear trend here that paying more typically equals better performance. So let's take a look at some of the outliers.

• Marshall paid under $500,000 for their defensive staff, and were 30 points over the median S&P+. Clearly an underpaid staff this season.
• Auburn looked quite different, paying second most, only to Bama. They were above the median S&P+ by roughly 14 points. That's still above average, mind you, but not nearly worth the price of investment, which is why they recently tabbed Will Muschamp to correct the issues.
• Texas A&M and South Carolina both paid around a million fewer dollars than Auburn but also performed below the S&P+ median. There's a reason A&M is looking for a new DC and South Carolina probably is too.
• You could make an argument that Alabama, despite paying more than anyone in college football for their defensive staff (notably, half of the staff's total cost is Kirby Smart), are actually under paying based on performance.
• Michigan State, Ole Miss and Mississippi State all represent pretty strong cost effectiveness, ranking in the top 10 in S&P+ while paying a value that ranks in the 20s.
• LSU theoretically overpays, paying the 4th highest amount and performing the 7th best, but that's honestly quibbling. They are above the trend line, so still getting good value.
• Quite the rebound for Manny Diaz, whose defense ranks 14th nationally in S&P+, but his overall staff is only the 67th highest paid on college football. Great value.
• Army is paying over a million dollars for one of the worst defenses in college football. At least Tulsa has the dignity to keep their shittiness cheap.