The 7 O’Clock Club: Does a more explosive, successful or higher-scoring offense keep its defense off the field more?

It’s 7 o’clock somewhere…

The 5 7 o’clock club is published from time to time during the season, and aims to provide a forum for reader-driven discussion at a time of day when there isn’t much NFL news being published. Feel free to introduce topics that interest you in the comments below.

I keep reading comments here on Hogs Haven that suggest that, with a more explosive offense in 2021, Washington’s defense won’t be on the field as much. The idea is, I guess, that the offense gets in more plays, so that leaves fewer snaps for the other team’s offense.

With my way of thinking about NFL football, that seemed counter-intuitive to me. In my mind, a game isn’t so much like a pie, where a bigger slice for the offense means a smaller slice for the defense. It is not made up of a set number of plays; instead, it has a flexible “size” as the 60 minute clock stops, starts or continues to run based on what’s happening on the field.

To me, a conservative offense burns up more clock and “shortens” the game by limiting the number of drives for each team. My thought, then, was that if the offense is relying on a lot more deep passing, the clock stops more often, the offense scores faster, and the defense spends more time on the field.

It was only about 4 years ago, when I started doing some research on turnovers and their effect on a football game, that I realized that most NFL games have between 23 and 25 drives. You get some outliers (last year’s 20-19 loss to the Giants had only 16 drives), but generally speaking, you generally get 10 to 12 drives in the first half, and 11 to 14 drives in the second half, when the clock management is a bit different. That’s why controlling turnovers and field position are so much more important than almost anything except the points on the scoreboard.

I figured that the defenses that were on the field the least were the ones who were complemented by a conservative offense that relies on runs and high percentage passes. My thinking was that big play offenses have a lot of incomplete passes and penalties that stop the clock and lengthen the game. I figured as well that big play offenses have shorter drivers (a 48-yard pass play moves the offense a lot faster than 6 eight-yards runs) that tend to put the defense back out there.

In short, my feeling was that big-play offenses would end up putting their defensive teammates on the field more than an offense that focused on short passes and runs. My hypothesis, then, was that the switch from conservative Alex Smith to YOLO QB Ryan Fitzpatrick would see Jon Allen, Chase Young, Jamin Davis and Kam Curl heading out on the field more frequently, with shorter breaks.

I’ve been pondering this for weeks, and it’s been bothering me that I couldn’t easily find the answer to the question: which type of offense results in its defense having to play more?

I eventually decided to test my theory with multiple regression analysis. Anyone who has done this kind of analysis knows that there’s a bit of ‘try it and see’ to isolate the specific variables that need to be measured. I tried a few ideas, and in the end, decided to use number of offensive plays in the season and points scored in a season as simple proxies for offensive explosion and success (my independent variables x1 and x2). If I had been working on a doctoral thesis, I would have worked a lot harder to get more nuanced variables, but for a Hogs Haven 5 7 o’clock club post that will be forgotten 48 hours after being published, I was only willing to put forth so much effort.

My dependent variable, y, was number of defensive plays in the season.

My source was Football Outsiders 2021 Almanac.

Here’s a look at some of the results:

You’ll see that X1 (number of offensive plays) has a correlation value of -0.2597 while x2 (points scored) has a value of -0.1309.

The “minus sign” indicates that, when the number of offensive plays goes up or points scored is higher, the number of defensive plays goes down. This tends to support the folks who believe that a more explosive offense will keep the defense on the sideline.

Now, I’m far from an expert in any kind of statistical analysis, but when I studied this with Dr. Jacobson at VCU in 1978, he suggested that values of 0.25 and 0.13 meant that the independent variables don’t actually explain much. In other words, like my marriage to my ex-wife, the relationship isn’t strong.

This means that you won’t have a lot of success predicting outcomes with consistent accuracy if you rely on these relationships to make your predictions. While not quite random, the range of actual outcomes is too varied to predict how much a defense will be on the field based on what type of productivity is achieved by their offense.

I’ve got a table here; I highlighted a few teams in order to make some points:

The teams are ranked 1-32 for the three variables (offensive plays, defensive plays and ‘PF’ points for). The two offensive stats are ranked with the largest number at #1, while the defensive stat has the lowest number ranked #1.

Since defensive plays is negatively correlated, when this list is sorted on any of the three variables, the rankings would be identical or very close together if this data could be used to build a highly predictive model. In other words, if a team was #1 in offensive plays and #1 in points scored, that team would likely be #1 in defensive plays (the lowest) if the model were perfectly correlated and highly predictive.

You’ll see that the NY Jets, highlighted in green near the bottom of the chart, are a great example of this. They rank 31st in offensive plays, 32nd in points scored, and 30th in defensive play ranking (i.e. 3rd most defensive plays in the NFL). This is what most people predict.

Another good example is the Saints, highlighted in green near the top of the chart. They ran a lot of offensive plays (9th most) and scored a lot of points (5th most), and their defense ranked 4th (that is, 4th fewest defensive plays). Like the Jets, this is what most people expect.

But we also have teams that are almost the complete opposite — teams that follow the pattern that I predicted where a more explosive offense puts its defense on the field more. Highlighted in blue near the bottom of the page, Dallas and Arizona were both near the top of the league in offensive plays run (ranked 2nd & 4th) and in the middle for points scored (17th & 13th) but among the lowest ranked in terms of number of defensive plays (24th & 26th).

The flip side of these teams is the NE Patriots. They had a very low number of offensive plays and scoring (ranking 29th & 27th) but managed to have the 6th fewest defensive plays.

The Patriots were a slightly more extreme example of what happened with the Washington Football Team in 2020. The Football Team was 15th in number of offensive plays and 25th in scoring, yet had the 8th lowest number of defensive plays in the NFL last season.

I’m not sure how much I learned from this exercise. I guess I learned that, in broad terms, other people were right(er) and I was wrong(er); more offensive production is negatively correlated to the number of defensive plays, so, very generally, a team that creates a lot of offense tends to limit the amount of plays the team’s defense spends on the field.

However, the relationship is so weak that it can’t be used to make reliable predictions. Teams like Dallas, Arizona, New England and Washington were more strongly correlated in the positive direction then the negative.

Clearly, the relationship is deeper and more nuanced than the hypothesis I tried to test.

I’m well aware that several commenters on this site, some part-time writers, and guys like staff writer James Dorsett are actually professionals in the field of statistical analysis and know what they are talking about. To all of you, I apologize for utilizing the remnants of my memories from my late-20th century Statistics 101 course. You don’t teach grammar; I shouldn’t attempt quantitative analysis.

If any of you guys would like to tackle this question in a more meaningful way, I would be fascinated to read your findings.

Until then, I’ll be rooting for an explosive, productive and high-scoring Football Team offense this season, combined with a menacing shut ‘em down defense, no matter how much that proves me wrong.

Week 1: Chargers 3 Football Team 38