Wednesday, February 15, 2023

Adjusting Receiving Yards for 'Inflation'—Equitable Footing For Past Era Receivers

 By John Turney 
Don Hutson
The NFL's passing game has exploded over the last forty-five years and it means receiving yards are easier to get than in previous generations, relatively speaking.

There are, of course, counterarguments to everything but rule changes allow for linemen to block in ways they could not prior to 1978, and defensive backs cannot defend like they could prior to 1978.

The passing game is much more sophisticated, but so have defensive coverages. Players now get far more reps and are much better athletes than in previous generations. 

But now, they throw a much higher percentage of passes, giving many more opportunities to pile up yardage so it really comes down to how much to adjust for the era. 

One thing is for certain, players of the 1950s played twelve games, from 1978 through 2020 they played sixteen, and in between they played fourteen, so that is one factor that is easy to adjust for.

Greater minds than ours can do a much better job someday but we used 1950-69 as the baseline, an average of passing yards per game from that time, and then made adjustments pre-1950, the 1970s, and then from 1980-2022.

Pre-1950, players (and the only one in the top twenty-five is Don Hutson) gets a fifteen percent increase. It should be a little higher but he was such an outlier it is hard to get a fix.

The dead ball era of the 1970s gets a ten percent bump. Yes, the rule changes took place in 1978 but the yards passing per game began to rise more sharply in 1980. 

From 1980, to adjust for the "inflation" yards are reduced by fifteen percent. Is this about right? Too much? Too little? It is a little too generous strictly going by the numbers but perhaps makes up for the defenders being better, but they are as equal to the task, relatively speaking, as the defenders of the past.

So, if someone wants to debate the inflation rate, we'd gladly concede, tell us the number, use a rolling average, and we'd be all for it. 

However, this is how it shakes out given the parameters we've set out—
Don Hutson played, generally, ten games a season. So the big jump was prorating his yards over fourteen-game seasons. Then the fifteen percent era adjustment was added in. It takes him to fourth all-time.

And of course, Jerry Rice stays at number one. Don Maynard and Charlie Joiner make big jumps and Terrell Owens and Randy Moss drop to six and seven followed by Isaac Bruce.

Essentially, players whose entire careers were played after 1979 keep 74.4 percent of their years which is about equal parts adjusting from sixteen games to fourteen and era adjustment.

Others had to be adjusted differently because they played part of their careers in the 1970s and/or part of their careers in the 1950s with a twelve-game schedule.

Don Hutson got a 49.4 percent increase and 80.2 percent of that is just the conversion from a nine and ten-game schedule to fourteen games. 

So, as a back-of-the-envelope calculation, it does give players from previous generations more equitable footing to be compared to modern players.

15 comments:

  1. Interesting way to do it and of course there is no perfect way. One thing I'd add though is that it is much easier to play longer now. Rather that be because of modern medicine, training, less damaging hits, etc. Like if Rice started in 2000, i think there's a good chance he plays a couple years more than he actually did. Whereas, if Rice started in 1970 i dont think he'd play as long as he did. I'm not sure how to account for that but maybe something similarly can be done.

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    1. There could be an adjustment like picking top 7 seasons, or top 9 something like that. Or and average...or a formula. . . try to level the field as much as possible then do an adjusted average per 16 games, something like that.

      To me, main point is a 1970s -1,000 yard season today, in terms of actualy achievement is maybe 1,300 or 1,350 yards or so

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  2. You divided a number by another number? Whoa! And now you have a pile of numbers that aren’t real. Advanced!

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    1. Yeah, well I am not capable of doing anything advanced I am just not that intelligent.

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    1. Correct. It worked for Ben Franklin and countless others. You got a problem with that?

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  4. this method by chase stuart is better at handling the "inflation" issue than lumping every guy into an era and adjusting by a flat %. https://www.footballperspective.com/adjusted-catch-yards-over-worst-starter/

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    1. If by “handling” you mean changing it into something meaningless, not real, and that has application in the real world, then by all means read Chase Stuart.

      Turney missed the point. Simpler is better. There’s no need to chase these digit diddlers.

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    2. Nothing wrong with what Chase, and Bryan Frye did - they are smart guys, I am not, I deserve the dunce cap you've put on me.

      They adjusted for era but also added in a bonus for TDs and catches...fine. They did excellent job.

      However, Bryan advised me on this. Told him of what I was going to do, we had long chat about it, about smoothing, about everything I did. He said it was reasonable. He didn't say great, perfect, or endorse or anything like that just "reasonable".

      We discussing the rolling averages and I told him that was too much work and he understood and we both agreed it would be better done that way but for me a short post to make a point it wasn't worth it.

      I saw that there was not much difference in passing yards per game between 1950 and 1969, not enough to go year-by-year in a rolling average. If Mr. Anonymous or anyone wants to do that, fine. I said that in the post. I would like to see the results of anyone going to that trouble.

      So flattening the 1980-2022 yards is simpler than doing a rolling average, though there is a bump in 2017, I believe. Over time, things flatten out according to the numbers. And given there are valiables than cannot be accounted for in any model, Stuarts, Frye's, or Michio Kaku's, there is no real reason to pick nits.

      So a flat rate over eras is justified if it is based on the passing yards per game and the passing yards per game are similar over that era. That is what they did, but they did their bonuses and so on, I didn't do all that.

      Stuart and Frye take past yardage and adjust forward and it's pretty cool. This takes currant yards backward.

      Rather than say, Jerry Rice having a "value" of 2758 and Don Hutson 1921 in their best seasons, this would give Hutson credit for a 14-game season and Rice credit for a 14-game season and deduct Rice some for playing in a passing era and increase Hutson for playing in a running era. . . but not as much as the actual "inflation" rates because they were pretty stark and also I smoothed for simplicity.

      The point show is a reasonable, fair manner what one idea shows what receiving yards inflation, not to the exclusion of any other ideas. Which is specifically mentioned.

      Also this is just a post on a blog, I mean, it's really nothing to troll about.

      Well, maybe it is if you hate me that much, so okay, by all means, troll away dude.

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    3. Deducting things rice actually did is not reasonable imo

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    4. It is either that of adding things in to guys like Hutson and other they did not do. RIce played 16-game seasons. Hutson played 10-game seasons.

      There had to be an adjustment forward or backward. Then one played in a passing era, the other in a running era. Same issue, adjust forward or backward. Either way it is a metric . . . meant to put players on a more reasonable footing.

      There are other ways to do things...as a percentage of league totals year-by-year. I have done that. But it's hard to explain.

      I have a receiver formula, based loosly on the passer rating formula, utilizing four categories. It has it's flaws.

      This has a purpose simply to show what happens when seasons are reduced to a level 14-game season across the board and if a smoothed adjustment for era is made.

      The fact that it draws a little bit of ire means it has served its purpose.

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    5. Better to project what they might have done than erase what they did do

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    6. Either one is a metric. Same difference.

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  5. From Brian wolf ...

    Yeah, the Yardbirds with Jimmy Page on rhythm guitar and Jeff Beck on lead did a song on the movie Blowup called Troll On ... oops, I meant Stroll On ... haha

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