LenDale White, Chris Johnson, running back use and success

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I believe I’ve mentioned on here a couple of times that, in terms of evaluating running backs, I don’t particularly care for yards per attempt. After all, a lot of runs go for about 2 yards, and the difference between average 4.5 and 4.3 yards per carry is 1 gain for 20 instead of 10 yards every other week. Instead, I prefer the statistic success rate, which I learned about from Football Outsiders.
What success rate is is a measurement of how close a carry comes to picking up first down yardage-a carry on first down is a success if it gets 40% of the yardage to gain, on second down carries 60%, and third and fourth down carries 100%. And, if you run the numbers for the Titans this year, you find that, through four games, LenDale White and Chris Johnson, have the exact same Success Rate, 43.3%. Johnson is averaging over 5 yards a carry, White under 2.7. Despite this massive disparity, have they really been about as good this year?
The answer, unsurprisingly, is of course not. (What, you didn’t think I was going to write a post defending White, did you?) The explanation is an old friend, and the reason I prefer Success Rate to yards per carry as a measure-the addition of context. Johnson and White have had roughly the same number of carries (67 and 60, respectively), but when you look at carries by down-and-distance, that Johnson is much better than White becomes clear.
Take, for instance, the most common play in football, 1 and 10. Helpfully, each of White and Johnson has had 30 of his carries come in this situation. 15 times, a Johnson run on 1&10 has gained at least 4 yards-a very good 50% Success Rate. White, by contrast, has had a successful carry only 10 times on 1&10-a poor 33% Success Rate. Put it like this-the Titans are 50% more likely to end up in 2&long if they give White the ball on first down than if Johnson gets the ball.
And 2nd and long is where the disparity between the two backs, and the reason for Johnson’s equal Success Rate despite being a superior back, comes clear. I noted based on preseason stats that the Titans had lots of difficulty running on 2nd and medium and 2nd and long. Those difficulties have continued in the regular season. Overall, White has a 44% Success Rate on 2nd down, while Johnson is at 39%. Looking inside those numbers, though, and the problems of 2&7+ become apparent. White has carried the ball 8 times in such situations, and has been successful 3 times. Johnson has superficially good per carry stats, thanks to his 51 yard run against the Bengals on 2&12, but overall has only been successful on 3 of 16 carries on 2&7+, a 19% Success Rate. Now, I don’t have league-wide stats for rushing success on 2&long, or even Titans stats for prior years, but it’s clear to me that having to run on 2nd and long is a losing proposition, and Johnson’s looking worse because of it.
What about third down, you ask? White has converted both times on 3&1, 1 of 3 on 3&2, and failed on 3&5, for a total of 3 conversions on 6 attempts. Johnson has, by contrast, only converted on 4 of his 11 3rd down carries. Once again, a little context is in order. Johnson has 1 carry on 3&1, 1 on 3&2, and 1 on 3&3, and converted all of those. He also converted 1 of his 3 carries on 3&5, for a total conversion rate of 67% on his 6 carries that are akin to White’s 6 carries. Johnson, though, has 5 additional carries, each from 7 yards or more out. Unsurprisingly, he has not managed to convert on any of these plays. Now, the leaguewide Success Rate on runs on 3&long isn’t 0, but that doesn’t mean it’s actually any good-that Johnson has failed in this situation is not necessarily a negative reflection on his ability.
So, how should we get a true comparison between White and Johnson? The difference in usage is that Johnson has gotten 2/3 of the runs on 2&long and all of the runs on 3&long. So, let’s pretend like he got White’s workload-half-weight his 3/16 on 2&long and ignore his 5 carries on 3&long. Take those away, and what do you have? White’s Success Rate is still 43.3%, while Johnson’s has now improved to 50.9%. What my eyes and the per-carry statistics were telling me is now confirmed-Johnson has clearly been more successful than White. He just didn’t look better because he was put in a position to fail more often, a position he was put in precisely because he’s a better back. When it comes to football and statistics, even in the use of more advanced statistics, context still matters.

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8 Responses to “LenDale White, Chris Johnson, running back use and success”

  1. Matt Says:

    Excellent article Tom.

  2. Seth Leonard Says:

    Indeed, a fine examination. Of course, we all know you aren’t a Lendale White fan, so is there a bias?
    I’m guessing no, because the numbers make him look bad enough. Personally, I still like White. He probably could hit the treadmill a little more often, but he fills his role well. Also, we must remember that both of these guys are young, like really young. Johnson is a rookie and Lendale is what, 22 or 23? Plenty of time for Lendale to improve on his fat-ass ways and for Chris to gain a few pounds of leg muscle. Also, CJ needs to work out in the pass skeleton or whatever the Titans receivers use to improve their hands–you cant be a ‘faster Brian Westbrook’ if you cant catch everything.
    Regardless, nice work, Mr. Gower.

  3. Robert F. Ludwick Says:

    Nice insight. YPC is a pretty poor statistic until you factor in the context of the run like you have, nice approach. Perhaps next time you can explore the conditions of each running play other than just yardage, such as status of the other 21 players on the field, field position, time on the clock, score, etc.
    A running back will likely have a lower YPC if they are running late in the game to run out the clock, and that’s not an indication of ability really. That’s an indication that the opposing team’s defense had loaded up against the run.
    This is why NFL scouts and coaches have a tough job. They have to factor every variable in when evaluating talent. They can’t just go by some simple statistics. They have to take everything into account.

  4. Tom Gower Says:

    Thanks for the compliments, guys. I wasn’t sure what I’d get when I started keeping track of the backs and their situational carries, but I think this post turned out reasonably interesting.
    One thing I didn’t note in the post is the baseline for success changes if you have a lead in the fourth quarter-it falls from 40/60/100% to 30/50/100%. It also increases if you’re down by more than a touchdown in the 4th quarter (to 50/65/100%, I think), but that’s something the Titans haven’t faced this year. I’m not swearing Success Rate is always right, and simply running clock alone can be hugely valuable.
    I was lazy when I put together the dataset-from the official PBP, I pulled RB, down, distance, and week, and noted, for the purpose of Success Rate calculation, when the first 4th quarter run was. Quarter info would be something useful to have, and relatively easy to add. Formation info would mean re-watching the first 3 games exclusively for that, which is probably too tedious for me to actually do. I also don’t really want to re-derive something like DVOA.

  5. Jared Says:

    I dunno too much about statistics, but just watching (as much of the game as i can in CA) the past 2 years with L White and to be honest I’m impressed still, even though he’s not the “better back.” He still ran over 1000 last year and is friggin unstoppable on the goal line. I’ve never seen such an overweight and awkward RB before in my life but production is production and he’s an important part of the offense and doing the Titans proud. I bet the Chargers wish they had someone to back up LT like White does to Johnson. Reminds me of another “thunder and lightning” duo from a few years ago… can anyone say Steelers?

  6. wheels Says:

    Good article Tom. I don’t know if this violates any site rules but here goes. I am driving down from NYC to Baltimore for the game this Sunday and was wondering if any Titan fans had 2 extra tix to sell. I am willing to pay a fair price but would rather sit with Titans fans. Let me know by emailing me at hesse23@aol.com. I’ve only seen the Titans one time…the first great Giant comeback down 29-13 in 4Q and won 32-29. Hoping for a similar result! Thanks.

  7. Dave Says:

    Wheels, I don’t blame you for wanting to sit with other Titan’s fans. I hope that this community can help you out.

  8. jerryt. Says:

    it’s going to be a good game so were ever you sit hold on to your popcorn & drink and enjoy 4 quaters of LIGHTS OUT football. GO TITANS…

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