By Robby Jeffries
@robbyjeffries

The 2018 NFL Combine has come to a close and rookie hype is surging to new levels as we barrel full speed towards the 2018 NFL Draft. There were many surprises and exciting storylines that emerged from this past weekend. In the world of fantasy football, we saw impressive performances from the likes of Mike Gesicki (TE, Penn. State), DJ Moore (WR, Maryland), DJ Chark (WR, LSU), Nick Chubb (RB, Georgia), & Saquon Barkley (Superhero, Penn. State). 

One non-fantasy related performance (unless you are wild and play IDP) I would like to highlight was the stellar athletic performance of one Shaquem Griffin, linebacker from the University of Central Florida. Chances are, you have probably heard his story from various reporting or word of mouth. I highly recommend checking out his Letter to NFL GMs. His incredible combine was something was something really cool to see.

I conducted a very scientific research project on the dynasty Twitter chatter of 2018 dynasty rookies by comparing the pre-combine chatter to the post-combine chatter. Below are the results.


*Please do not ask for the methodology as it is verrry complex.

As you can see from my extensive research, despite Barkley dominating the chatter, other names popped up into the discussion. 

Now, all joking aside, there has been quite a bit of hype for some of the players I listed above and how they are moving up rookie draft boards after their impressive performances at the combine. I’m no dummy and understand that an all-around good score at the combine usually is indicative of a good athlete, which in turn can produce good NFL players. But, I’ve always been one to question everything I see/read and wanted to know more on how, specifically, wide receiver 40-times correlated with NFL production. This curiosity trended from the hype of a relatively quiet prospect before the combine began. As I perused through Dynasty Twitter on the Saturday (the day WRs ran through drills), I noticed a lot of hype and a growing sense that DJ Chark, WR out of LSU was about to rise in upcoming rookie drafts after running a 4.34 40-time, which ended up being fastest of the WR group. The following question arose for me:

Does a fast 40-time correlate to better fantasy production in the NFL?

Before LSU and Chark fans burn me at the stake, let me emphasize a disclaimer…

DISCLAIMER: The following study is not in any way, shape, or form intended to try and prove that one, DJ Chark, is going to/not going to be a viable/productive NFL wide receiver or NFL fantasy player for many years to come. Any usage of Chark’s name will be simply to describe the “perceived” lack of conversation about a player before their 40-time performance and the abundance of conversation following an impressive time in the aforementioned drill. If you take the time to read this, tweet me @robbyjeffries asking  “Why do you hate DJ Chark?” to illustrate a mutual understanding.

Back to our question of, “Does a fast 40-time correlate to better fantasy production in the NFL?” To answer this, we must quantify what a fast 40-time is and how we measure fantasy production.

Methodology

For this study (which I promise is a tinge more thorough than the study above), I wanted to take no more than the top 10% of combine 40-times as the threshold for “fast” 40-times. I decided to gather data from all the times ran by WRs from 2008’s to 2015’s combines. I chose 2008 as a clean number of ten NFL seasons of NFL production to pull data from. Further, I looked at earlier 2000’s years’ combine numbers and there were fewer and fewer people who hit the sub 4.40 mark (which became the threshold for “fast” times), which in turn would fiddle with the percentages. I also eliminated WR times from the 2016 and 2017 combines, noting that the average NFL career is just over three years and these wide outs have not yet played three seasons, which would affect their production. My combine data is pulled from nflcombineresults.com

As a standard of measurement for NFL production, I focused on top end fantasy production as this is a fantasy football related article. More specifically, top-24 fantasy wide receiver production based on annual position rank from Pro Football Reference. The top-24 wide receivers imitates common fantasy lineups of starting at least two wide receivers on a weekly basis in a 12-team league.

Limitations

I’ll be the first to admit, I never took a stats class in college. I don’t quite know how to measure statistical significance and I won’t be deep diving into analytics. However, I can reference other studies that did just that and point out the similarities between their results and mine. Some great pieces on whether combine results have any correlation to NFL production are posted below.

https://harvardsportsanalysis.wordpress.com/2012/02/27/does-the-nfl-combine-matter-offense/

https://www.stat.berkeley.edu/~aldous/Research/Ugrad/Paul_Park.pdf

Further, one could argue that the 25th ranked WR has just as much value as the 24th ranked WR, however I had to chose a threshold and in your standard fantasy league of 12 teams that starts two wide receivers, the top-24 would all be starters.

Data Analysis

Now that we have established a threshold for a fast 40-time and NFL production, we have split the combine numbers into groupings. I separated all time into three groups:

1. Fast (4.37 and faster): represented by the fastest 15% of all 40 times. Note, that I could not get exactly to 15% as adding another .01 hundredths of a second would have tipped me over that 15% threshold.

2. Middle (4.48-4.63): represented by the middle 70% of all 40 times.

3. Slow (4.64 and slower): represented by the slowest 15% of all 40 times.

I then scoured all 382 WRs that ran the 40 at the combine from ’08 to ’15 and researched if they had produced any seasons as a top-24 fantasy WR (no small undertaking I might add) according to Pro Football Reference. I then split them into the same time groups of Fast, Middle, and Slow based on their corresponding 40-time.

Results

What I found was both surprising and unsurprising at the same time. The percentage difference from the population to Top-24 WRs was unsurprising for the “Slow” group. With a 6% decrease it was evident that WRs who had slower 40-times were statistically less likely to end up as a top-24 wide receiver for fantasy. On the flip-side, I found that there was a similar percentage increase for the “Fast” wide receiver groups. Now, these results could stem from a range of reasons but I would like to highlight my main theory.

WR’s with faster 40-times are more often drafted at a higher percentage, as well as drafted higher in general than WRs with slow 40-times. The biggest hurdle to NFL production is making it to the NFL. I did note that no WR, except for Jonnny Knox, that ran in the “Fast” group became a top-24 wide receiver if they were drafted lower than the 3rd round.

Top-24 WRs who ran 4.37 or faster:
'09 - Mike Wallace 4.28
'09 - Johnny Knox 4.29
'11 - Julio Jones 4.34
'12 - TY Hilton 4.37
'13 - Tavon Austin 4.34
'14 - Brandin Cooks 4.33
'14 - John Brown 4.34

The mean 40-time for each group was:
’08-’15 WRs Combine Mean: 4.51
‘8-’15 Top-24 WRs Combine Mean: 4.48


Conclusion

The main takeaway I found from this is that “fast” 40-times shouldn’t really increase your perception of a fantasy wide receiver to an extensive degree. While there is small correlation between faster 40-times and NFL production, it is a small amount. Whatever value you placed on a, say DJ Chark, before seeing his 40 times should relatively be the value you have after seeing his 40-time. So long as wide receiver avoids a “slow” 40-time, their value should be consistent when examining their 40-time and attempting to project their NFL production.

Please feel free to reach out to me via Twitter at @robbyjeffries if you would like the data I gathered from which the (second set) charts were created.


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