The case for Clemens

by Russ Roberts on January 29, 2008

in Sports

Here’s a statistical analysis of the career of Roger Clemens, purporting to show that his career trajectory is similar to that of Randy Johnson, Curt Shilling and Nolan Ryan, three people who presumably did not take steroids. The point is that it’s not THAT unusual to be successful in your 40′s and that Clemens’s performance didn’t spike when people think it did. The analysis is done by the agents who represent Clemens in contract negotiations.

Is it a convincing analysis or an example of how to lie with statistics? I’m only reporting on this one. You decide. I like the charts, though. Nice use of color to make the case.

UPDATE: J.C. Bradbury does his own analysis of Clemens (HT: Matt C.) and shows that Clemens strikeout and home runs relative to the rest of the league declined with age as you might expect if he weren’t a user (or if steroids make no difference). There’s no obvious spike relative to the rest of the league. Interesting. He does not look at the key questions of whether the decline is slower than for other pitchers or relative to the past. I would assume that all players are working harder to stay in the major leagues because the returns are higher to baseball than they used to be. On the other hand, younger players are working harder to make it into the league, so maybe there’s no difference.

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caveat bettor January 29, 2008 at 2:05 pm

Isn't cherry picking 3 of the top 1% of pitchers as one's sample already damning in its bias?

Matt C. January 29, 2008 at 2:28 pm
Brad Hutchings January 29, 2008 at 2:49 pm

When the standard is "prove you didn't do it", Clemens' agents have to make this presentation not to show that there might be a chance that he can still pitch, but that there isn't a chance he'll get caught using banned substances. And it's not to get him a shot at a contract, it's to get him a shot at a contract at his price.

Right now, I feel like Clemens has about a 20% chance of exposing this steroid witch hunt charade for what it is, perhaps a tad higher if he is telling the truth. I could see him accepting a lowball contract and turning around suing George Mitchell and MLB for the difference. This analysis reads like a telescoped punch. The Mitchell Investigation was a terrible error in judgment and execution from the beginning. Baseball has testing in place. If that's the route they're going to go, they should have just accepted the problems from the past and let them test out or age out.

Daniel S. January 29, 2008 at 4:35 pm

While I agree that it is difficult to prove that Clemens did not take steroids, I am unimpressed with this report. "ERA Margin" is not a commonly used statistic, since it is a raw measure of performance relative to average. In contrast, ERA+ shows a pitchers performance relative to league average in percentage terms. That being said, it is worth noting that (unlike the other pitchers he's compared to) 5 of Clemens' top 12 seasons in terms of ERA+ occurred after 1997, when he supposedly began using steroids. The charts in the report show that he has two large peaks in "ERA Margin" after 1997, while the other pitchers follow more of a normal rise and fall pattern (taking into account injury years, particularly for Schiling and Johnson). While I don't feel that this is enough evidence for us to conclude Clemens used steroids, I think it calls into question the analysis used by his legal team.

FreedomLover January 29, 2008 at 7:16 pm

I think the steroids witch-hunt should end. So what if a player is juicing, how does it undermine the credibility of the product?

hgh January 29, 2008 at 7:38 pm

under what basis would you assume that Johnson, Shilling, and Ryan didn't use performance enhancing drugs? Simply because they were never named in a report?!

the fact is that performance enhancing drugs pervade every single level of amateur and pro sports in the world and have for decades (high school and up). Serious testing has only been going on for the past couple years. And it's still not that serious.

World-class athletes get to be that way by grabbing every once of opportunity in front of them. Drugs are one of those opportunities.

One problem is "steroids" is far too narrow a word. HGH is essentially undetectable. EPO was thought to be a distance drug until Kelly White confessed that every top sprinter was on it. Depending on the sport, guys will do ritalin (for focus), or asthma inhalers (o2 intake). You can see quarterbacks getting shots of cortisone in the shoulder on the sidelines! What, that's not "performance enhancing"? it's sure not good for you long term.

No, the only solution is to allow everything, tell me what you're on and we'll watch later when you're paying the price.

FreedomLover January 29, 2008 at 9:47 pm


That's the sanest thing I've read on the whole thing. But the "powers that be" think that the average Joe sportsfan wants witch hunts day and night. I always hated George Mitchell when he was a senator and now even more so.

BGC January 30, 2008 at 1:34 am

Steroids and HGH are probably used by pitchers mainly to recover faster from injury.

If so, this would be very difficult to detect statistically due to the individual variation in drug dosage, nature and severity of injury, and response to the drug.

In fact it would be difficult to know whether the drugs really were effective without a fairly long n=1 trial comparing a dozen or so episodes of injury.

Jeremy January 30, 2008 at 10:16 am

You could publish all the statistical analyses in the world to show that Roger Clemens couldn't pitch his way out of a wet paper bag, but that is not the issue. The problem for me is that a guy went under oath and said that Clemens did steroids. Not whether or not he looks like he did them, pitched like he did them, admits that he did them. The issue is not whether he has a clever lawyer who can "publish statistical analysis." The issue is not whether or not the Mitchell investigation was a valid use of time and money. So if we are going to sit here and pretend that being under oath means something for people like Bill Clinton but not anything for people like Brian McNamee, then there isn't much left to be said for the American judicial system.

I am surprised that Austrians are buying into this.

tw January 30, 2008 at 10:30 am

Jeremy is correct that Clemens' biggest hurdle is Brian McNamee, and all the statistics he comes up with can't help him with the big question: Why would McNamee tell the truth about Andy Pettitte, but lie about Roger Clemens?

That's Clemens' biggest problem. Pettitte has already admitted that what McNamee said about him….that he used steroids briefly while rehabbing an injury…is true.

And now word comes today that Pettitte is going to confirm that Clemens talked to him (Pettitte) about HGH, apparentely as testified to by McNamee.

Nick January 30, 2008 at 5:56 pm

"That's Clemens' biggest problem. Pettitte has already admitted that what McNamee said about him….that he used steroids briefly while rehabbing an injury…is true."

It isn't like Pettitte is all that credible. I think you're approaching blind faith to believe Pettitte's story that the only time he ever even thought about using steroids just happened to be the two occasions McNamee testified about.

I'd be a lot more interested in a pre-steroid era comparison than in the Schilling-Johnson-Ryan comparison. And if such a comparison is difficult or impossible because so few pitchers pitched into their 40s maybe that in itself ought to tell us something. And of course there's the fact that Clemen's joints are completely shot…..hmmmm. Wonder why? I'm guessing it has something to do with all that clean living.

FreedomLover January 30, 2008 at 7:38 pm

Nobody's accusing Randy Johnson of cheating.

vidyohs January 30, 2008 at 8:24 pm

"Much ado about nothing."

Sports at any level are a pasttime no more no less, anyone who devotes a nonosecond of time or a penny of money in hardcore interest/adoration of athletes or the games they play has simply too much time on their hands and not enough time being spent on the vitals of life, such as who the F..k is that with the hand in my(rhetorical) pocket, and why is it there?

I believe all of us should be paying total attention to those fellow humans who are devoted to stealing everything from us, wrecking our economy, debasing our moral character, and where to dispose of their bodies.

Clements could pitch stoned, Bonds could bat totally wired, and I personally would just consider it amusing.

This is from a guy (me) who was a hardcore amateur athlete who loved the rush of competition, but I never could kid myself about who was benefiting from my efforts.

Sports to play, oh yeah!

Sports to watch, ho hum!

FreedomLover February 1, 2008 at 3:12 am


Apparently most Americans are more obsessed with pro sports then the government thieving from their pockets. It's truly a sick society.

JK February 2, 2008 at 5:45 pm

I agree with tw that Clemens's biggest problem is that Pettitte already admitted what McNamee said about him. Because why would McNamee lie about Clemens but not Pettitte? It just doesn't make much sense to me.

"It isn't like Pettitte is all that credible. I think you're approaching blind faith to believe Pettitte's story that the only time he ever even thought about using steroids just happened to be the two occasions McNamee testified about."

Just because Pettitte may have used it more that what McNamee said doesn't necessarily mean he's not credible. Maybe that's all that McNamee knew about. It's not like Pettitte would admitt to taking steroids for more times than he was accused of.

Maybe I'm being bias since I don't like Clemens, but it seems that there's enough evidence that he used steroids.

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