A Critique of the Clemens Report

In today’s NY Times Keeping Score column, several Penn economists are critical of “the Roger Clemens report”. In particular, the authors feel that comparing Clemens to three excellent pitchers who excelled late in their careers is a dodgy tactic.

A better approach to this problem involves comparing the career trajectories of all highly durable starting pitchers. We have analyzed the progress of Clemens as well as all 31 other pitchers since 1968 who started at least 10 games in at least 15 seasons, and pitched at least 3,000 innings. For two common pitching statistics, earned run average and walks-plus-hits per innings pitched, we fitted a smooth curve to all the data from these 31 pitchers and compared it with those for Clemens’s career.

Relative to this larger comparison group, Clemens’s second act is unusual. The other pitchers in this durable group usually improve steadily early in their careers, peaking at around age 30. Then a slow decline sets in as they reach their mid-30s.

Clemens follows a far different path. The arc of Clemens’s career is upside down: his performance declines as he enters his late 20s and improves into his mid-30s and 40s.


Clemens Aging Comparison

I have a few comments. First, the reason his career is upside down in terms of WHIP is because of his walks. Clemens’s career pattern in preventing walks is bizarre, as I previously documented, but walks are not the thing I think of when I think or performance gains from steroids.

Walk% Above Avg.

On the other hand, his strikeout performance did decline with age, which means that the decline in walks likely was not the product of being able to pitch more in the zone.

Strikeout% above Avg.

The authors are also critical of the Clemens Report for using ERA because “a pitcher’s E.R.A. is affected by factors, like defense, that have nothing to do with his pitching.” But, using WHIP doesn’t solve this, because all hits except home runs involve the defense.

As to the comparison with other pitchers who excelled at advanced ages, this is not meant to demonstrate Clemens’s performance path was expected. Clemens’s aging pattern is certainly atypical. See Cy Morong’s evaluation of an aging cohort that includes Clemens. What these comparisons do convey is that such performances have been observed before, and therefore just because Clemens performed in this way doesn’t mean that steroid use is the only possible explanation. Clemens aging pattern is not the norm, but it is also not odd enough to prove anything.

Finally, I’d like to reiterate that Clemens’s most suspicious late-career spike (2004-2006) occurred at a time when McNamee was working for Clemens but had no knowledge of steroid use. It would be odd that he would get the drugs from McNamee in 1998, 2000, and 2001; but then find another source. And given that I don’t find McNamee to be a compelling witness, I am inclined to believe Clemens pitched clean until I see some better forensic evidence.

The authors, for whom I have great respect, bring something interesting to the table, but I don’t interpret the findings to be an indictment Clemens. Although, I agree with them that the Clemens report is not a compelling document. I think it was unnecessary, and it has served as a focal point for criticism rather than to exonerate the pitcher.

Addendum: I received an e-mail from Randy Hendricks explaining some of the impact that the Clemens report did have, particularly in dispelling the common misperception that Clemens was done in 1996. I guess I was a bit narrow-minded in my interpretation, since I already knew this. Thus, I was incorrect in calling the report unnecessary.

10 Responses “A Critique of the Clemens Report”

  1. Greyson says:

    “I am inclined to believe Clemens pitched clean until I see some better forensic evidence.”

    I can’t believe the naivety of that statement. As unfortunate as it is, I find it hard to put a presumption of innocence on ANYONE involved in baseball over the last 2+ decades, certainly not when there are so many questionable characteristics involved. (For me the bat throwing incident with Piazza seals the deal, that clearly was not a human being acting naturally.)

    Your discussion of BBs and Ks also presumes too much. HGH and steroids could certainly lead to increased velocity, which would allow an aging pitcher to continue peppering the strike zone, rather than make adjustments. This would certainly lead to fewer walks, and arguably fewer Ks as opposing batters would be able to sit on the heat, which leads to more contact, even if not the most productive contact.

    Does any of this mean he shouldn’t be in the Hall of Fame? Probably not, but it certainly means people should stop trumpeting him as the best pitcher ever, he’s a thrower. He is clearly surpassed by Maddux within his era, and probably a dozen pitchers from the past.

  2. Steve says:

    “I can’t believe the naivety of that statement.As unfortunate as it is, I find it hard to put a presumption of innocence on ANYONE involved in baseball over the last 2+ decades…”

    You probably should have just stopped right there. It’s pretty clear your arguments are motivated more by personal bias to the situation than rational argument. To call someone who has done extensive research and discussion on the topic naive because he does not agree with your gut instinct is pretty childish.

    In the only portion of your post where you discuss anything he actually wrote, you talk of J.C. presuming too much in his discussion of walks and strikeouts since HGH and steroids “could certainly lead to increased velocity, which would allow an aging pitcher to continue peppering the strike zone…”. Although steroids would seemingly enhance performance, you assume that HGH does the same when the scientific literature does little to back you up on that. Truth is, HGH hasn’t been shown to increase baseball performance. On the other hand excellent fitness and nutrition, something Clemens is known to promote, would likely play a role in a pitchers health and ability. Who is to say that his workout regiments aren’t to blame for his performance spike? Following this, you argue a specific pitching style and scenario in which it would be feasible to explain Clemens’ numbers in the context of increased velocity from steroids and HGH. All that you’ve logically proved from that statement is that it is physically possible for you to be correct. J.C. never argued otherwise for that.

    While I personally feel that Roger Clemens is guilty, it is not an open and shut case. If you are going to assume he is guilty and leave it at that then it is probably a waste of time to argue why it makes sense to be skeptical on the situation as a whole. But even you can understand the value in taking a look at the available evidence and making an objective decision on the issue. J.C. did just that.

  3. Donald A. Coffin says:

    Any comparison using performance levels of a group of players which reports only the mean level of performance (on whatever performance indicator) is next-door to worthless. We also need to know about the variation in perfromance for that group. So the average pitcher yielded 1.29 (or so) (W+H)/IP at age 40, while Clemens yielded 1.2 (or so). What’s the standard deviation in the group’s performance? (And, raising a different question, how much of the difference is in W/IP and how much in H/IP? ) If the S.D. is 0.045, then the 90% confidence interval 1.2 to 1.38. So Clemens is at the bottom of that range? So what? Someone has to be.

  4. Greyson says:

    Steve: First, I wasn’t calling JC naive, only the comment that granted Clemens a presumption of innocence. Presumption of innocence is a great foundation for a legal system, but it makes a really shoddy base for a moral system. The one thing the Mitchell Report should’ve shown everyone involved with baseball is that the game has been exceptionally dirty over the last 2+ decades, and thus I think it is naive to think anyone is innocent. I love John Smoltz, but I do worry about his rehabilitation and recovery. If anyone were to come out with as much evidence and as many shady characters as they have around Roger then I would be leaning to believe it as well. (On a side note, I rooted for Clemens throughout his career with BOS and TOR, and was addicted to his nintendo game for years. I had no personal dislike of the man, excepting the bravado and idiocy of the bat-throwing incident that I mentioned, until this whole mess surfaced.)

    Second, JC says “walks are not the thing I think of when I think of performance gains from steroids,” but what can their possibly be to gain from steroids if it isn’t increased velocity and an ability to challenge hitters? Note two important words (since this IS a rational argument, the words are important): “could” and “and.” I felt it necessary to point out the counter-argument, and avoid an error by omission, but I certainly am not claiming to have proven my case, so I used the word “could.” I used the term HGH AND steroids, because I believe that Clemens probably used them both, and at least some part of the cocktail helped to increase velocity, as well as maintain strong muscles/ligaments/tendons to allow him to pitch more frequently and for longer times.

    The last 2+ decades of baseball have fallen under a cloud, and we simply can’t ignore this. I’m not out to pillory the man, or to put any asterisks in the record book, but I am out to show people that this era is as different from the ’40s, as the ’40s were different from the dead ball era. As I said, I think Clemens deserves to be in the HoF, because he was ONE of the best pitchers of his era, an era that was thoroughly infiltrated with performance-enhancing substances. I don’t want to see anyone measuring his numbers up against Warren Spahn, Bob Gibson, or even Nolan Ryan though, and unless you’re claiming that Greg Maddux’s 82 mph fastball is steroid-aided then I don’t want to see anyone putting Roger ahead of him either.

    And to JC: Thank you for your blog, I do respect your work a great deal, but I also know you expect more from your readers than to nod and agree with everything you posit.

  5. dave says:

    I actually find clemens drastic increase in production from 96-97 suspicious. JC, don’t you find it strange in the mitchell report that clemens knew he couldn’t inject himself? don’t you think that leads to the possibility of him at the very least trying to use steroids before? perhaps having someone else inject him?

    in the report it also states that clemens asked mcnamee about Anadrol-50. Now my question is, why didn’t he ask the same questions about winstrol? Does it make sense to you that he will ask mcnamee about one steroid, but not the other? From the looks of it, clemens didn’t need to ask about winstrol because he was using it before and knew the benefits they provided.

  6. dave says:

    I guess the point of my post above is, Roger Clemens steroid use, in my opinionm started in the 1997 season.

  7. Marc Schneider says:

    Without becoming too philosophical about it, that statement makes no sense. Presumption of innocense is a moral system because it is based on the idea that people should not make assumptions based on personal feelings and impressions. It sort of bothers me that people look at things like the presumption of innocence and seem to think it is just a “legal technicality” that has no place in the real world. That doesn’t mean that you need to have the same quantum or quality of evidence to arrive at a personal opinion as you do to convict someone in a court of law but I do think as a matter of simple fairness you should refrain from assuming someone is guilty just because others may have been. For one thing, much of the conventional wisdom about steroids and HGH is just wrong, as JC has repeatedly pointed out. I think many people are making conclusions based on assumptions, for example, that because player A is bigger, he must have been taking steroids. This is just an example of how this steroids issue has become, in my opinion, a bit of a witch hunt.

  8. Sal Paradise says:

    As I said, I think Clemens deserves to be in the HoF, because he was ONE of the best pitchers of his era, an era that was thoroughly infiltrated with performance-enhancing substances. I don’t want to see anyone measuring his numbers up against Warren Spahn, Bob Gibson, or even Nolan Ryan though, and unless you’re claiming that Greg Maddux’s 82 mph fastball is steroid-aided then I don’t want to see anyone putting Roger ahead of him either.

    This is what really kills me.

    Have you looked at the power numbers of many of the hitters who have actually been caught using steroids? There is absolutely no reason to believe that the person needs to be big/strong/throw hard to use steroids.

    What if Maddux used steroids to maintain an 82 mph fastball rather than a 72 mph one? Why does it somehow mean more when it’s 98 to 88?

    Baseball has never been clean. Steroids is just the most recent way to cheat.

    Why does everyone act as if this era is somehow special in that respect? Have you just ignored the history of the game, or are you caught up in the ‘witch hunt’ as Mr. Schneider put it?

  9. Marc Schneider says:

    Steroids are bad because they are dangerous but there are a lot of sanctimonious people about as Mr. Paradise implies. Does anyone really think the players in the 30s, 40s, 50s, 60s, etc. wouldn’t have use steroids if they had been available? Athletes are always looking for whatever edge they can get. There certainly took amphetemines. And records are highly contextual anyway. No one hit 50 home runs until they livened up the ball. I would argue that you shouldn’t compare any records in any sport between eras. Jerry Rice wouldn’t have caught all those balls if he played in the NFL of the 60s or 70s with the bump and run defenses. Spahn and Gibson pitched in mych less hitter-friendly eras. The point is, even if Clemens did use steroids, they didn’t make him a great pitcher any more than steroids made Barry Bonds a great hitter. And, frankly, I don’t care all that much if the era is tainted. I enjoyed baseball then and I enjoy it now. I certainly would prefer that players did not take dangerous drugs to improve their performance but I can’t understand this feeling of betrayal that people seem to feel.

  10. Sal Paradise says:

    And, frankly, I don’t care all that much if the era is tainted. I enjoyed baseball then and I enjoy it now. I certainly would prefer that players did not take dangerous drugs to improve their performance but I can’t understand this feeling of betrayal that people seem to feel.

    It sounds like someone is taking PEDs for enjoyment. Someone stop this man before he actually cracks a grin and cheers for the sport he loves! Think of the attendance records that may be broken!!!

    Should we put an asterisk next to fan enjoyment and revenues too?