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Wednesday, July 18, 2007
Do pitchers today have it better because of medicine and technology?
The strike zones of the 60s really ate many pitchers arms up – Jim Maloney, Drysdale, and there weren’t nearly the corrective practices that are in place since the 1970s, with pitch count restrictions, arm surgeries and Tommy John too. That’s important because injuries that ended careers prior to about 1975 wouldn’t end careers anymore. It would be like saying John Smoltz’ career would be over about 5 years ago. He’s still pretty good.
—Chris Dial
Fantastic point. It’s one of those thoughts that only a real baseball fan could even form as a conjecture. But, is it true?
Here’s what I did:
- Start with the Lahman database and figure a player’s age as the season minus his birth year
- limit the players to those born between 1895 and 1974
- limit to seasons of ages 25 to 32
- create an “age class” of 25-28 and another one for 29-32
- add up each pitcher’s BFP (batters faced by pitcher, or PA) for each age class
(At this point you should have 6242 records. If you don’t, then either you did something wrong, or I forgot to tell you about another selection criteria.)
- create 10 time periods in groups of 8, so that pitchers born 1895-1902 are in “time period 0”, all the way to pitchers born 1967 to 1974 as part of “time period 9”.
- select the top 16 pitchers in each time period in terms of BFP
(For the most recent time period, Brad Radke is the leader with 3781 BFP between the ages of 25-28.)
- for each of those pitchers, figure out how many BFP at ages 29-32
- produce totals by time period
Here it is:
Start End BFP2528 BFP2932 BFPrate
1895 1902 65104 52107 0.800
1904 1910 64991 51805 0.797
1912 1918 54623 24650 0.451
1919 1926 60297 40284 0.668
1927 1934 58587 43790 0.747
1935 1942 66387 50791 0.765
1944 1950 70399 51449 0.731
1951 1958 59784 45865 0.767
1959 1966 62328 48614 0.780
1967 1974 56981 43459 0.763
The Start and End columns represents the birth year of the pitchers. (Radke would be part of the last group.)
BFP2528 is the total number of batters faced by our top 16 warriors at ages 25-28.
BFP2932 is the same for ages 29-32.
BFPrate is BFP2932 / BFP2528.
We can see that there’s a time period where WWII greatly diminished the pitcher’s careers, as expected. The two slight sticking points are the pitchers born 1944-1950 (meaning they played as early as 1969 and as late as 1982) and those born 1959-1966 (meaning they played as early as 1983 and as late as 1998). The former group retained only 73% of their batters faced, while the latter group retained 78% of their batters faced.
We can see where Chris Dial is coming from. We all remember the 70s as the time period where pitchers were used very heavily, and so, it would be easy to accept that they couldn’t sustain that level of use. And, the Tommy John and medicine years certainly helps our 1980s and 1990s pitchers. However, that difference is fairly small. And furthermore, our recent crop of pitchers (perhaps “too babied") show endurance levels of post-integration, without the medical advancements. As well, since we are only talking about 16 pitchers in each group, these small differences could very well be a small sample size issue. The average difference between the two groups of pitchers we are discussing is +/- 25 batters per season.
What if instead of looking at 16 pitchers, we look at the top 32 pitchers in each 8-yr time period?
Start End BFP2528 BFP2932 BFPrate
1895 1902 114562 88107 0.769
1903 1910 117790 93486 0.794
1911 1918 95940 56273 0.587
1919 1926 102995 69343 0.673
1927 1934 103807 79452 0.765
1935 1942 121779 86813 0.713
1943 1950 131594 93516 0.711
1951 1958 109172 78073 0.715
1959 1966 114434 87520 0.765
1967 1974 107617 81950 0.761
In this case, we do see things start to shake out. The pitchers born 1935-1958 (meaning they played as early as 1959 and as late as 1990) do show a sustained difference. It’s the same amount of difference, but with a larger sample of pitchers. Again though, the difference is not the chasm we may have expected.
The pitchers born since 1959 (meaning they played as early as 1983) maintain a greater share of their batters faced at age 29-32 compared to age 25-28. However, this didn’t really help them. Why is that?
Of the 96 warrior pitchers born between 1935-1958, they faced an average of 3777 batters at ages 25-28, and followed that up with 2692 batters at ages 29-32 (a 71.3% retention rate). The pitchers born from 1959-1974 faced an average of 3470 batters at ages 25-28 (that is, babied by 307 batters over those 4 years), and followed that up in their ages 29-32 years with 2648 batters (76.3% retention rate). Both groups of pitchers, the “overused” legendary pitchers and the “babied technology” pitchers both ended up facing virtually the exact same number of batters at ages 29-32! Astonishing, isn’t it?
What if we look at “major” drops?
Start End drop50 under1700 sustain
1895 1902 4 4 15
1903 1910 6 6 14
1911 1918 18 17 8
1919 1926 10 11 8
1927 1934 5 8 11
1935 1942 10 10 13
1943 1950 6 5 8
1951 1958 6 7 13
1959 1966 4 3 12
1967 1974 6 7 12
drop50: number of pitchers who faced at least 50% fewer batters at ages 29-32 compared to ages 25-28.
under1700: number of pitchers who faced less than 1700 batters at ages 29-32
sustain: number of pitchers who faced at least 90% of their 25-28 batters at ages 29-32
(As a point of reference, the typical warrior faces around 900-1000 batters per season.)
That 1935-1942 time period comes up again for pitchers who ended up losing a substantial portion of their careers. But of pitchers born since 1943, there’s no additional dropoff in our technology years.
The short of it all is that, barring war, the average warrior pitcher since Babe Ruth was born has averaged around 2700 batters faced at ages 29-32, regardless of their use at ages 25-28. Medicine, techonology, babying, overusing have not had the impact we would expect.
What I haven’t yet studied however is their level of performance. I’ll get to that next time.
UPDATE (17:15):
Let’s see if their performances were affected. Continuing with the 32 warrior pitchers of each time period, I will focus on the aggregate W/L record, relative to their teammates. This is a simple enough measure. And when you look at 128 player seasons in each time period, alot of the funky stuff that goes with a W/L record goes away in the aggregate.
Start End Wins2528 Wins2932
1895 1902 0.523 0.524
1903 1910 0.518 0.522
1911 1918 0.505 0.511
1919 1926 0.538 0.509
1927 1934 0.521 0.511
1935 1942 0.542 0.525
1943 1950 0.550 0.529
1951 1958 0.527 0.515
1959 1966 0.562 0.526
1967 1974 0.552 0.533
Wins2528: W/L record, after adjustment relative to teammates, at ages 25-28
Wins2932: Same, for ages 29-32
If we focus on the post-WWII pitchers (see the break above), we can see that our warrior pitchers are above average at ages 25-28, as we’d expect. After all, the only pitchers who can accumulate innings over a period of 4 years ought to be a good pitcher.
We can also see that their performance at ages 29-32 is about halfway between their age 25-28 performance and .500, pretty much across the board. (If we look at runs allowed, we see a similar 50% regression toward .500).
So, what do we have? We saw that by babying our pitchers at age 25-28 that we did not get an extra mileage out of them at age 29-32. We were hoping then that maybe we’d get stronger performances. And, we didn’t really get that.
In terms of getting an aging curve for warrior pitchers at ages 29-32, I would propose the following:
Start with the average number of IP at ages 25-28. That’s the base IP. And start with whatever’s your favorite way of figuring out a pitcher’s “true” W/L performance. That the base Wins.
Then, follow the RULE OF TEN:
For Innings Pitched
Age 29: 10% less IP than base IP
Age 30: 10% less IP than Age 29
Age 31: 10% less IP than Age 30
Age 32: 10% less IP than Age 31
This will give you an average of 77% innings at age 29-32, relative to the base IP.
For Wins:
Age 29: .010 less wins than base Wins
Age 30: .010 less wins than Age 29
Age 31: .010 less wins than Age 30
Age 32: .010 less wins than Age 31
This will give you an average of .025 less wins at age 29-32, relative to the base wins. (Actually, .024, because of the weighting.)
This does NOT necessarily apply to non-warrior pitchers, nor does it necessarily apply to 33-yr and older pitchers.
UPDATE (18:00):
I repeated the exercise, but this time my base year is ages 29-32, and the followup years are ages 33-36. I cutoff the ending birth year to 1966.
Here it gets more interesting. First off, it doesn’t look like many of the older players went to war, as there is not the big gap like with the younger players. From players born from 1895 all the way through 1958, the retention rate for BFP was around 60%. However, for the players born since 1959, the retention rate was 69%.
It seems that perhaps medicine and technology is helping the older players the most. However, remember that we really don’t care about the retention rate of BFP, but rather gross BFP. And, there’s nothing great about the recent crop of pitchers. Excluding the war pitchers, the average BFP for ages 33-36 is 2200. For the recent pitchers, it’s 2300.
Once again, nothing top point to looking at recent pitchers to find better comps. The W/L performance of the more recent pitchers has been fantastic at the age 33-36 class. However, I’d be wary of sticking to that premise. Otherwise, pitchers drop their performance rate at the same .010 level. The BFP level drops at a 20% clip, year-to-year.
So, we can give an aging curve of a .550 pitcher with 220 IP as the following, starting at age 29:
Age IP Wins WAR
29 198 0.540 3.5
30 178 0.530 3.0
31 160 0.520 2.5
32 144 0.510 2.1
33 115 0.500 1.5
34 92 0.490 1.1
35 74 0.480 0.8
36 59 0.470 0.6
That last column is wins above replacement. As you can see, the standing aging drop I’ve been using, 0.50 wins lost per year, seems to hold up pretty well.
UPDATE (19:30):
To finish this off, I took the age 33-36 warriors and see how they performed to the rest of their career. They also retained about 60% of their BFP, except for the most recent pitchers who retained an enormous 81% (and still going!). Even their performance has been fabulous. It’s possible that today’s technology and medicine is helping the older pitchers enormously.
So, when you are looking for comps, it’s much more important that for the older pitchers that you focus alot more on recent pitchers. Dial’s premise likely holds under this age class of pitchers.
UPDATE (Thursday):
Take a pitcher’s entire career. Select the 64 pitchers with the most BFP for each time period. Average them.
start end BFP
1895 1902 8,208
1903 1910 8,781
1911 1918 6,648
1919 1926 7,112
1927 1934 7,401
1935 1942 10,199
1943 1950 10,658
1951 1958 9,216
1959 1966 9,955
As you can see, of pitchers born since 1935, there has been no change in batters faced. Pitchers do have a certain mileage on their arms. And, the babying of pitchers in their 20s is prolonging their careers in their late 30s. However, the total mileage is still the same!
Here’s the results for the top 32 pitchers instead of 64:
start end BFP
1895 1902 10,691
1903 1910 11,425
1911 1918 8,509
1919 1926 9,492
1927 1934 9,573
1935 1942 12,687
1943 1950 13,463
1951 1958 11,426
1959 1966 12,313