Tuesday, February 12, 2008

How Well Has Roger Clemens Aged? (Part 4)

To see what I have already done, click on Part 1 and Part 2 and Part 3. So far, I have not found that in his late thirties or early 40s that Clemens had an unprecedented improvement. Early 40s was good, but not the best. Late 30s was not good, with many pitchers doing better than he did. I have looked at many stats, sometimes adjusting for park effects and league averages. Pitchers that show more improvement than Clemens include Nolan Ryan and Dennis Martinez.

In this post, I simply show that both Ted Lyons and Cy Young also either showed significant improvement late in their careers or did unusually well. In the graphs below (the last thing), the pink line is strikeout-to-walk ratio (not adjusted for the league average. The blue line is ERA+ (from Baseball Reference). It adjusts ERA for the league average and park effects. A 120 means the pitcher is 20% better than average. But I divided the ERA+'s for each guy by 100 to fit in the graph. So 120 would become1.20.

To give you an idea of what I found, when Cy Young was 39, his ERA+ was 86. When he was 40, it was 129. So it went up 50%. When he was 41, it was 194. so it went up 50% again. When Clemens was 40, his ERA+ was 112. When he was 41, it was 146. So it went up 30%. When he was 42, it was 226. So it went up 55%. Those two events look very similar. Just one year difference in age. Cy improved even more over the two years than Clemens. Young also had a big spike up in ERA+ at 34.

Then there is Ted Lyons. Here are his ERA+’s from age 32 on


He pitched 180 innings at age 41 in 1942. Even in 1942, most of the good hitters had still not joined the military (Williams and DiMaggio, for example were still there). Lyons had a career ERA+ of 118. So in his late 30s and early 40s, he was generally pitching well above his career average. My point is that late career improvements are not totally unheard of (although not common). Notice his strikeout-to-walk ratio more than doubled late in his career. I am not sure what Clemens has done in terms of an unusual age profile is much different than Lyons or Young. Now the graphs. Age is on the horizontal axis and strikeout-to-walk ratio & ERA+ are on the vertical.


Minus said...

Roger Clemens major improvement, IMO, is his 1997 season. I would consider the age of 34 to be "old". Do you know of any other pitchers who around that age would have the best season of their career?

Cyril Morong said...

Thanks again for dropping by.

First, I don't think we should just look at one season. But it is possible that a guy could take PEDs one year and not the next.

Yes, Clemens had his 2nd best ERA+ at age 34 (221). His best was the 226 at age 42. That may be the unusual thing, best two at 42 and 34. One thing I might do is look at the average age of pitchers' best 3 or 4 seasons and see who comes out on top. I would have to call up a bunch of pitchers and that would take some time. Maybe Clemens would come out on top.

But his third best year was at 27 with 213, not too far behind. It does look like his best consecutive 3 year period might be from ages 41-43, just eyeballing ERA+ figures at Baseball Reference. But he switched leagues and the NL has not been as good as the AL these last few years (by inter league records) and in one of those years he only pitched 113 innings. I don't how much difference that makes.

In the graph you can see that his best season in SO/BB is clearly at a younger age. His early SO/BB ratios seem to be a bit better than his older ones.

Cy Young's best ERA+ was at age 34, but he switched leagues (1901, first year of AL). But, his second best ERA+ in the AL years was at age 41. All of the sudden he had has best year, by far, in 7 years. Also suddenly, are big increases in SO/BB ratio from ages 36-38, with 39 also being extremely high.

Lyons had his best ERA+ at age 41, his 2d best at age 38, and 3rd best at age 34. His best SO/BB ratios are at ages 38-41 (by far).

So I am trying to say, we have seen some great improvements before at old ages

Minus said...

Cy - Good points about young and lyons. I also enjoy dropping by because I've read some of your other work, and I enjoyed it.

Im not really all that concerned with his stint in Houston. While it's certainly suspicious, it can be attributed to a lesser workload, improved defense in Houston, and the NL. Still, his 2005 season is eye-popping, and no doubt a bit suspicious.

His age 34 season seems suspicious to me. He clearly showed signs of a decline phase, and then suddenly bursted with the best season of his career, and arguably of his era. Yes, he was good in 1996, but good pales in comparison to the monster we would see in 1997. His 1990 season was fantastic, but his ERA+ as you pointed out was 8 points lower, and he pitched almost 40 less innings, and completed 2 less games. In 1997 he pitched with better quality, with more quantity, and he was 34 then compared to age 28 in his best pre-toronto season.

Look, I'm not saying he used steroids, or he didn't. We'll probably never learn whether or not he did. And I'm not even saying what he did is unprecedented, but in my opinion it's very suspicious. So while I can't say he used steroids and that it enhanced his performance, if we do in fact learn later that he did take steroids, in my opinion they would have benefited his performance, even if all they did was provide him with the ability to recover from his workouts and injuries quicker. Again, I could very well be wrong, but that's my opinion.

Anyway, good research, hope to read more soon.