In baseball, Bill James pioneered a concept called “similarity scores.” The whole idea is that a player that wants to be considered for the Hall of Fame should be similar to other Hall of Famers. So, he would take every single counting statistic (hits, runs, HR, RBI, BB, SB) and find the players most similar to any particular player. We can use the same concept in football.
People are obsessed with franchise quarterbacks. How do you know when you have one? NFL teams have done this for us. We are taking the top ten highest paid quarterbacks (not including Aaron Rodgers and Kyler Murray) and coming up with a composite (or numerical average) performance over a set of ratio statistics. In other words, these are percentages and not totals. The second group of quarterbacks are the next group of ten in terms of pay. Finally, we have the final group of ten that we would classify as either very young or possibly replaced. We are removing the Cardinals (Murray) and Stroud for now.
We are looking at touchdown percentage, interception percentage, yards per attempt, quarterback rating, ESPN QBR, and PFF score. Theoretically, the top ten paid guys should be better than the next ten and so forth. From there, we can simply check to see who Stroud is the most similar to as a group. We will identify that group and then begin comparing Stroud to that group instead of to the other rookies.
Tier One: 4.15 TD%, 2.14 INT%, 6.99 Y/A, 92.5 Rating, 58.1 QBR, 78.1 PFF
Tier Two: 3.90 TD%, 2.57 INT%, 7.09 Y/A, 90.5 Rating, 56.1 QBR, 76.2 PFF
Tier Three: 3.97 TD%, 2.74 INT%, 6.72 Y/A, 81.5 Rating, 43.3 QBR, 68.4 PFF
We should start by looking at these numbers. Obviously, who you choose to put in each group of ten makes a big difference. There were some tough cuts. Brock Purdy went in the third group even though he is largely considered as established as a starter. Ryan Tannehill is being paid like a second tier guy, but is performing like a third tier guy. When you switch those two then the distance between tier two and tier three becomes more significant.
The idea is to get a big enough sample size and then determine whether there really is a separation between the tiers. After all, most of the guys in tier one are making 40 million or more a season. You’d like to think that you are actually getting something for the investment. In some categories this is not true. The money numbers appear to be touchdowns and interceptions. Obviously, scoring points is the name of the game. The touchdown to interception ratio went from 1.94 to 1.45 for tier three. That’s a significant difference.
The yardage and rating numbers are not nearly as significant in terms of a difference. We are only six games in. Maybe players like Joe Burrow start turning things around and creating more of a gap. The concept is fairly simple. You pay for gaps and you pay for gaps that matter. If I am paying you more than the next guy then you need to be better than the next guy. More importantly, you need to be better tat things that actually matter.
Where is C.J. Stroud?
No more comparison is going to be absolutely direct, but we end up going with a preponderance of the evidence. Is Houston Texans QB C.J. Stroud performing like a franchise quarterback? Obviously, that is a loaded question. Those guys are paid a ton for a reason. He’s not there yet after six games, but we still want to compare him with the appropriate group of quarterbacks to be fair to them and to him.
TD%: 4.20 (Tier One)
INT%: 0.50 (Tier One)
Y/A: 7.80 (Tier One)
Rating: 96.4 (Tier One)
QBR: 55.5 (Tier Two)
PFF: 73.3 (Tier Two)
So, you could label Stroud as a tier one or two quarterback depending on your point of view. PFF and ESPN view him as a tier two quarterback, but all of the other numbers see a tier one quarterback. Since you are familiar with these numbers we will use them to evaluate Stroud from here on out. At the end of the season we will see where these quarterbacks stand as a group to see if there has been a shift.