My original plan for a post this week was to talk about college football wide receivers and who I think is having the most productive season in college football right now. But I ran into a problem. The problem is that wide receivers are a giant pain to evaluate. In fact, it gets incredibly frustrating to evaluate and project the performance of wide receivers.
The first question is what to use as an evaluation metric. Before you can begin to predict “performance” in any useful way, one has to settle on what “performance” means. Do you want yards, touchdowns, yards per reception, yards per target, touchdowns per target, fantasy points, what?
The question of dependent variable is crucial to understanding every analysis that comes afterward. All the conclusions drawn from analyses done will only be relevant to the dependent variable that one chooses. Therefore, it is crucial that one choose the “right” dependent variable. Sadly, there is little consensus regarding what the right variable is to use to evaluate wide receivers. So you’re stuck having to simply pick one. I pick a witches-brewed version of yards per target. It works for me, but it may not work for you.
Depth of Target
Once you’ve “solved” your dependent variable problem, you run headlong into another one. Generally, whatever DV you choose is somehow correlated with depth of target. Wide receivers that get thrown to farther down the field rack up more yards, generally get more touchdowns (that one is a bit tenuous, but I digress), have more yards per reception, and more yards per target. So now you’re stuck with a problem of understanding how the wide receiver fits into the offensive system regarding average depth per target. Does this receiver have low yards per target because they are not a particularly good receiver or because they are consistently being asked to be a “chain-mover” out of the slot? This calculation is impossible in some circumstances and tricky even with witches-brewed data.
Small Effect Size
You know what actually predicts production at receiver? Targets. End. This is a graphic I made showing the relationship between targets and yards in college football.
— Football Figures (@FBFiguresOnline) October 17, 2014
Targets accounts for around 75-80% of the variance in yards, which means that there isn’t much variance left for differences in ability to do any work. You could have a pretty decent receiver buried on a roster and they won’t look like much at all *cough cough Jarius Wright cough cough* And the reverse is also true. A relatively poor receiver could get a lot of targets and look like a golden god.
So, I wanted to post about wide receivers. I ended up getting frustrated at the position and writing about my frustration.