Deep Passing Study - There is Risk

Author: Bill Jones

Introduction

In our previous blogs, I analyzed the distribution of passes thrown in the NFL and explored the relationship between passing efficiency and location on the field. In this blog, I’ll take a closer look at the risk involved in different types of passes and locations on the field. A pass that is intercepted often quickly turns the tide of a game, and while throwing deep or to the middle of the field can be an effective way to gain yardage (as seen in last blog), if it also comes with a higher degree of risk it may be why NFL quarterbacks shy away from throwing to that part of the field. So, join me as I get into the risks associated with throwing the ball in different places on the field. Let’s get started!

Statistic Explanation

We will be looking at interceptions in this blog but that’s not the only statistic we will be using… I recently had the pleasure of meeting Ed Feng, founder of the website ThePowerRank, at a networking event during the Sloan Sports Analytics Conference weekend in Boston. We chatted about a variety of topics, but one that stood out was a statistic he is fond of called "bad ball" rate. Bad ball rate measures the percentage of bad throws a quarterback makes. So, what is bad ball rate? Here is my 3-line explanation of what Ed articulates in more depth on his website (thepowerrank.com) and podcast (The Football Analytics Show).

Ed defined it to me as any time the ball is thrown and the defender gets their hand on it, whether it's an interception, a batted ball at the line, or a deflected ball in the secondary. He uses this metric as a way to more accurately predict interceptions. Unsurprisingly, he found that interceptions (or interception rate) appear to be super unpredictable year over year, but the bad ball rate wasn’t as unpredictable. This makes perfect sense when you think about it. Bad ball rate helps to highlight situations where a quarterback is making poor decisions or putting the ball in risky positions, regardless of whether or not the defense actually intercepts it.

Ground Rules

Before I jump back into the analytics, I would like to remind the readers of the ground rules we will be playing with. The data used for this analysis was obtained from NFLFASTR for 2018 through 2022.

Visualizations and Analysis

Let’s jump into the analysis. Reminder if you didn’t read the last post (shame on you), deep passes and middle of the field passes are the most efficient from yards per attempt and completion percentage… As you can see, the below is in the same matrix format from last blog but now we are looking at interception rate and bad ball rate.

Analysis: There is a major turnover risk throwing the ball deep and down the middle of the field as we see increases in frequency for both interceptions and bad balls. What I find most interesting is the 20 through 40 air yards throws as there is a significant decrease in turnover risk when the football is thrown to the sidelines at these air yard depths. This reduction of risk for outside passes is not as drastic for passes under 20 yards or over 40. I now understand the lower volume of passes in the middle of the field and deep down the field as seen in the last post.

Conclusion

This concludes today’s blog on the negative side of throwing the ball down the field. In the next post, I’ll turn my attention to a player review, but don’t worry, this does not conclude the series, I will be coming back to deep passing. In a few weeks I’ll come back to talk about our deep passing but “From a Different Vantage Point”. Thanks for reading and stay tuned for my next post as I switch things up and do some player profiling!

*This blog post was enabled by ChatGPT. The text was generated by me, and the content is my own, but some sentences and wording were provided by the model. I take full responsibility for all information produced in this blog. More information about OpenAI and their technology can be found at https://openai.com.*