Baseball for the Thinking Fan

Login | Register | Feedback

btf_logo
You are here > Home > Primate Studies > Discussion
Primate Studies
— Where BTF's Members Investigate the Grand Old Game

Friday, September 02, 2005

A New Look at Pitcher Aging Patterns

The full version of Chris’ terrific SABR presentation.

In recent years it seems there’s been a huge number of age defying pitchers.  According to the research of Bill James,

players are supposed to peak at age 27, and have their prime around 27-30, but somebody forgot to tell a lot of current

hurlers.  Roger Clemens is
winning Cy Youngs in his 40s.  David Wells was a better pitcher in his late 30s and early 40s than he was a decade earlier. 

Randy Johnson had a historic peak in his late 30s.  Jaime Moyer never topped 14 win shares in a year before turning 35. 

Since then he’s done it five times.
Curt Schilling’s been far better since turning 30.  And then there’s Woody Williams, and Kenny Rogers and Kevin Brown, and…

Well, you get the idea.  Just how good are current pitchers aging, and more importantly - how well are they aging compared to

previous generations?

To figure this I took the info from Bill James’s Win Shares book (and its annual updates) and put together a database

organized by age of the pitchers for each year of their career.  I used every pitcher in major league history who had at

least 100 starts and a known birth year - 1179 guys in all.  Let’s cut the intro and get to the results.  First, here’s
the total list of win shares the pitchers earned at each age:

ALL 1179 PITCHERS - 132,680 WS

Age WS % of peak
15   0 0%
16 8 0.1%
17 36 0.3
18 162 1
19 685 6
20 1729 14
21 3327 28
22 5198 43
23 7511 63
24 9407 79
25 11153 93
26 11964 100
27 11883 99
28 11286 94
29 10692 89
30 9464 81
31 8430 70
32 6865 57
33 5767 48
34 4661 39
35 3661 31
36 2749 23
37 1894 16
38 1450 12
39 936 8
40 691 6
41 481 4
42 254 2
43 131 1
44 97 1
45 53 0.4
46 23 0.2
47 21 0.2
48 11 0.1
49 0 0

Looking at this chart, a few things stand out at first glance.

  • Age 26, not age 27 is the big year for the most pitcher, but it’s very close either way.  The real lesson I take from

    this is that there isn’t so much a Single Shining Peak
    Year, as much is there is a standard prime - ages 25-29 here.

  • There are some problems with this list.  First, it includes guys that are too damn young to really tell us anything about

    aging patterns. Kyle Lohse, Jon Garland, C. C. Sabathia all make the 100 GS cut, but they don’t really help us determine when

    pitchers are peaking.  Also, it includes guys from all sorts of different eras - the
    pitchers box era (1876-1892), the deadball era (defined here as 1893-1919), and the
    liveball era.  The differences in the eras could seriously impact how
    pitchers aged.

  • Let’s break it down into four groups:

  • Pitchers’ Box Guys
  • Deadballers
  • Liveballers born before 1960 (actually, 7/1/59)
  • Liveballers born in the 1960s
  • I want to separate the last group because enough of them are still playing and they could
    gum up the data.  Besides, the goal is to see how contemporary pitchers are doing
    against previous generations.  I’m including all pitchers and not just those still playing
    because to leave out those who were forced out of the game because they weren’t that good would
    skew the data toward old-agers.  Jack Armstrong was born within 12 months of Kenny
    Rogers - just as fair we treat them as such.  As for the guys since ‘69, we’ll
    just ignore them for now as they’re likely to be a source of noise.

    Also, to make the comparisons easier, I’ll not look at total Win Shares but
    at what percentage of the group’s peak was reached at each age.

    Age BOX   DEAD   LIVE   1960s
    18 6 1 1 0
    19 22 6 3 2
    20 46 16 8 7
    21 69 26 21 14
    22 83 47 32 33
    23 100 62 50 57
    24 90 81 69 73
    25 82 94 86 100
    26 76 98 100 97
    27 86 100 98 90
    28 57 96 97 96
    29 55 84 96 97
    30 37 69 90 88
    31 28 55 83 82
    32 21 43 70 72
    33 14 33 62 59
    34 10 23 52 50
    35 8 16 40 46
    36 2 11 32 42*  (1960-8)
    37 0.5 8 22 26*  (1960-7)
    38 2 5 17 22*  (1960-6)
    39 X 3 12 12*  (1960-5)
    40 X 4 8 12*  (1960-4)

    Baseball was a very different game back in the days of Old Hoss and
    the gang.  They were as good at age 32 as contemporaries are at age 38.  Shocking as it
    sounds, tossing 600 innings a year isn’t that good for the arm.

    They aged so poorly that it can easily distract one from recognizing how badly
    deadballers aged.  These guys tended to be worked harder in their early 20s than
    liveballers, and did fine in their prime, but once they hit age 29 they began a very rapid
    descent.  They aged a few years better than box’ers, but a few years worse than liveballers.

    So much for the preliminaries, now for the main event: how are
    contemporaries doing?  In a shocking development, I don’t see any evidence of improved aging patterns
    until they reach their mid-30s.  The gains are there, but it isn’t always easy to see
    how real it is because at the same time they rise up, they lose some of their pitchers.

    This is an important point because there is good reason to think the guys born at in 1968-9 (well,
    actually from 7/1/67 - 6/30/68 because that’s how I set up the database) won’t age as well
    as the earlier bunch.  Here’s a complete list of guys born in those last 24 months that
    pitched in baseballin 2004 (ordered from most to fewest win shares):

    Flash Gordon, Mike Mussina, Kent Mercker, Cal Eldred, Paul Abbott, Kevin Appier, Shane Reynolds, Andy Ashby,
    Hideo Nomo, and Donovan Osbourne.

    That’s a total of 34 win shares - 15 from Flash.  The problem isn’t that they’re not likely to age as well as the Big Unit or
    Jaime Moyer, but that only one or two of them has a chance to be as good as an aging Terry
    Mulholland.  Obviously, they’ll keep their lead at age 35, and I think their age 36 lead
    is safe, but after that I’m not sure that they’ll do much better at all when everyone’s done.

    ...um, so they’re not aging better?  Or just barely better?  Let’s
    look a little closer at the numbers and see what we find.  Let’s divide them all into
    decade-of-birth groups going back into the 1890s, the first decade where a large majority of pitchers
    were liveballers:

    Age 1890s 1900s 1910s 1920s 1930s 1940s 1950s 1960s
    20 15 1 7 6 12 12 9 7
    21 27 14 13 21 22 27 26 14
    22 41 26 20 23 38 38 39 33
    23 50 33 33 40 50 67 60 57
    24 72 51 56 60 69 80 77 73
    25 93 68 85 71 88 90 91 100
    26 94 88 100 87 100 100 100 97
    27 95 93 75 100 99 92 94 90
    28 97 100 91 98 85 83 86 96
    29 100 94 94 90 97 82 82 97
    30 96 91 92 88 86 73 72 88
    31 87 89 79 81 94 59 60 82
    32 66 77 66 66 64 59 56 72
    33 70 68 70 61 55 41 46 59
    34 58 55 60 52 46 37 36 50
    35 44 43 47 42 29 30 28 46
    36 30 39 34 30 21 26 23 42*
    37 23 27 27 19 15 18 14 26*
    38 16 28 18 12 11 13 8 22*
    39 12 17 13 9 6 10 5 12*
    40 8 10 5 6 5 10 4 12*

    The 1960s have the earliest peak season.  The things you learn when you dig
    through the data!

    Occasionally, the information is a bit fluky.  For example, there’s no reason
    that I can tell for why the 1910s did so poorly at age 27.  Sometimes the distribution of
    Win Shares within the prime is a bit random.  Odds are that’s why it’s as low as a 75
    there.

    Looking at all the data, things are getting a bit more interesting.  Current
    pitchers are aging much better than any recent ones as the previous 30 years’ worth
    of pitchers aged far worse than any other liveballers.  Just look at age 35—the
    1930s-50s are all at/under 30% of their peak value.  Everyone else is 42% at worst.  Mighty
    stark contrast - - and a very unexpected one.  I wouldn’t have thought that a group of
    pitchers that
    combined to have 6 300-game winners, 3 other 280-game winners would be part of the
    era that aged poorly, but that’s exactly what this says.

    How d’ya explain that?  Well, looking at their early 20’s, they were worked
    harder than any other group, except maybe the 1890s.  My guess is they were worked hard
    young, a disproportionate percentage of them hurt their arms and could not go on, but
    those that did could rack up the counting stats like no other group.  Thus you can have
    the bad overall aging patterns exist alongside all Seavers, Blylevens, Suttons,
    Kaats, and Carltons.

    Going back to the current pitchers, though they are aging better than the
    previous three groups, they are not aging better than the 1890s-1920s guys.  Age 36 and 40
    are the only ones they top, and when the 1968-9 guys are done, that may not even be the
    case.

    Meanwhile, at age 33 and 34, they are worse than all those guys.  What
    gives?  With all the medical care, new surgical procedures, and anti-inflammatories this
    information doesn’t make any sense.

    Two issues are clouding the data, only one of which I can really adjust for.  First, the one I
    can’t adjust for, is WWII.  This has a huge impact on some of the earlier groups.  It
    doesn’t impact the 1890s pitchers at all as they were all done by Pearl
    Harbor and only one - Hod Lisenbee - came back during it.  Hod earned zero win shares in his
    1945 return.  No impact there.

    The 1900s guys had a definite impact—the war artificially inflated their
    Win Shares totals in their 30s.  Several of these hurlers received a disproportionate share of their
    career value in their mid-to-late 30s, which not-so-coincidentally came during the war.  Topping the
    list were Johnny Niggeling, Ed Heusser, Rip Sewell, all of whom earned over 50% of
    their value in these years.  They were not alone as other, rather talented pitchers such as
    Claude Passeau, Bucky Walters, and Spud Chandler also earned around 1/3 of their
    career value over the same timeframe.

    Perhaps some were legitimate late bloomers, but even if
    they were, the war excessively amplified their value in these years.  Plus, there are still
    others, such as Boom-Boom Beck, who tied a career high for single season Win Shares in 1945 at
    age 40.

    The impact on the next decade-group was even more drastic.  Looking through
    the database, I searched for examples where a pitcher had been pitching prior to
    the war, lost some seasons, and then came back—war-related lost years.  I found 61 such
    seasons for the 76 pitchers in this group.  Their average age: 29.1 years.  The war
    reduced their prime, and thus made their production in their 30’s a greater portion of their
    overall value than it would have been.

    The impact is not nearly as strong on the 1920s pitchers.  Many, such as
    Bob Lemon and Vic Raschi got a late start because of the war.  Others, such as Warren
    Spahn, had lost seasons of their own.  It isn’t as easy to estimate time lost because every
    era has pitchers who don’t start until age 26 or 27, or a guy who gets a cup of coffee at age
    22 and does nothing for a while afterwards.  The main impact would be that many guys had
    their careers delayed, and thus had their arms less-taxed in their early 20s. 
    Given what happened to the 1930s-50s pitchers, that helped them a great deal.

    Still, the experience of the 1890s pitchers shows that WWII can’t be used to
    explain all of this.  And there is one other factor - the way in which MLB got the service
    of minor leaguers.  Here’s a much simpler chart: a complete list of all pitchers who
    did not have any win shares prior to their age 30 season yet went on to start 100 games along
    with their actual year of birth:

    1852 Ed Cushman 64 WS
    1886 Frank Miller 56 WS

    1893 Ray Kremer 141 WS
    1895 Bob Smith 135 WS
    1896 Heine Meine 54 WS
    1903 Curt Davis 165 WS
    1903 Johnny Niggeling 78 WS
    1903 Jim Turner 83 WS
    1907 Rip Sewell 139 WS
    1908 Bob Klinger 64 WS
    1911 Roger Wolff 58 WS
    1912 Mickey Haefner 88 WS
    1914 Ellis Kinder 145 WS

    1922 Connie Johnson 48 WS
    1965 Masato Yoshii 36 WS
    1965 Orlando Hernandez 62 WS

    11 of the 16 pitchers were born within 21 years of each other.  That’s a
    curious bunching.  Some are there because of WWII - Niggeling and Wolff are such
    pitchers.  Most aren’t, though.  Curt Davis gained a little bit from WWII, but he’d
    have 100 GS Hitler or no Hitler.  Ditto Rip Sewell.  And the first few guys were done by
    the time the US entered the war.  Something was up, and it wasn’t necessarily the war.

    Making the bunch-up even more interesting is the almost complete lack of
    such pitchers since then.  Of the three post-Kinder’rs, one was a major league pitcher in
    Japan, one was a Cuban defector, and Connie Johnson was a black pitcher.  Given that only 6 teams had integrated by Labor

    Day, 1953, I don’t see his status as comparable to the turn-of-the-century gang.

    What happened then?  Let’s look at the best pitcher in the bunch, Curt
    Davis.  Prior to
    joining the Philllies, he spent six years pitching for the San Francisco
    Seals in the PCL, at
    which time that league was as good a minor league as the 20th century has
    ever had.
    Though he was not a standout right away, he did have a breakthrough season a
    few years
    before coming to the Phillies.  Simply put, the turn-of-the-century guys
    were late bloomers
    who a generation earlier would’ve been overlooked entirely, and a generation
    later once
    the Branch Rickey minor league system had taken over, these men would’ve been
    spotted
    earlier and given their starts.

    This I can try to adjust for - call it the Curt Davis Adjustment.  Here’s
    how the 1890s,
    1900s, 1910s, 1920s, and 1960s look if you throw out all the pitchers with
    no win shares
    before their age 30 season:

    1890s 1900s 1910s 1920s 1960s
    19 5 0.3 3 4 2
    20 15 1 7 6 7
    21 27 14 13 21 14
    22 41 26 20 23 33
    23 50 33 33 39 57
    24 72 51 56 60 73
    25 93 68 85 71 100
    26 94 88 100 87 97
    27 95 93 75 100 90
    28 97 100 94 98 96
    29 100 94 92 90 97
    30 95 88 90 87 88
    31 83 86 75 81 82
    32 63 74 62 65 71
    33 66 62 67 59 57
    34 54 50 53 50 50
    35 39 41 42 41 45
    36 26 33 31 30 35 37*
    37 21 21 24 19 23 29*
    38 13 23 17 13 18 25*
    39 12 14 10 9 8 13*
    40 7 6 4 6 7 14*

    First, the number directly in the 1960s column is what unadjusted.  What I
    mean that 35 in
    the age 36 line means that what the pitchers born from 1960-8 did that year
    is 35% of
    what the pitchers born from 1960-9 did in their peak season.  The incredible
    thing is that
    the ‘60s are already ahead of everyone at age 36, and almost there at age 37
    even though
    they’re only at 90% and 80% of their full roster in those years.  The *‘d
    columns are
    adjusted, and they’re clocking everyone.

    This is even more remarkable when you realize that there’s still a WWII
    adjustment to be
    made to all but the 1890s.  Though their lead is impressive, it can
    be overstated.
    Again, there’s no real evidence that they age better until age 35.  Also
    since there’s no
    WWII adjustment for the 1890s guys, they make a good comparison for the
    1960s.
    Assuming that the guys born in the late 1960s age as badly as it looks like
    they will, the
    children of the ‘60s, though they will age the best, won’t be all that far
    in front of the men
    from the Gay ‘90s.

    Could this be taken further and adjusted for people who only had 5 Win
    Shares before their
    age 30 season?  That’s tricky because the worst pitchers in the study can
    rack up a good
    deal of innings in 5 win shares or less.  (Heck, Kevin Jarvis only has 12
    win shares total in
    his career, but he’s in the study).  Maybe move the year back a bit to 27 or
    28?  I tried,
    and it doesn’t change the results above.  The 1960s have actually had more
    late bloomers
    than any recent decade-group.  If you don’t believe me just ask Paul Abbott
    or Mark
    Gardner or Steve Sparks.

    Can I find an explanation for why they aged so well back in the days of
    populism, the
    Pullman strike, and the “glory days” of lynching?  Here’s a list of the
    1890s pitchers who
    earned the most win shares from age 30 onward:

    Dazzy Vance, Dolf Luque, Eppa
    Rixey,
    Charlie Root, Urban Shocker, Burleigh Grimes, Sad Sam Jones, Stan Coveleski,
    Jesse
    Haines, and Rube Walberg. 

    The leader is possibly baseball’s greatest late
    bloomer, and
    three are spitballers.  These pitchers did age better than their peers -
    though frankly the
    Grandfathered-In Gang didn’t age that much better than most liveballers
    (more on that
    later).  Still, they do help the 1890s guys as a whole and thus the 1960s
    pitchers post-35
    aging is that much better.

    So much for that question - let’s try a different one with the database: Are
    peak seasons
    changing.  I’m a little leery of this breakdown.  Normally I let Excel do
    the math for me,
    but I couldn’t get it to sort horizontally, so I had to go through by hand
    and figure peak
    season.  There’s a greater chance for error here.  Three groups: peak season
    for everyone
    born prior to 7/1/69; for all liveballers born before the 1960s, and then
    the 1960s group.
    Plus, off to the side a little chart saying what percentage of peak seasons
    are occurring
    when.  Let’s look at the results:

    Age Total Live 1960s       All Live
    17 - 1 0 0 17-9   0.6   0.0
    18 - 1 0 0 20-4   21.5 19.1
    19 - 5 0 0 25-9   52.6 51.4
    20 - 14 4 1 30-4   21.7 24.9
    21 - 29 12 0 35+    3.7 4.6
    22 - 44 18 3
    23 - 70 36 9
    24 - 98 64 8       1960s
    25 - 137 65 29 18-9   0.0
    26 - 145 85 22 20-4   12.9
    27 - 126 75 12 25-9   55.2
    28 - 108 68 13 30-4   23.9
    29 - 109 68 14 35+    8.0
    30 - 71 50 9
    31 - 71 46 12
    32 - 44 29 7
    33 - 47 34 5
    34 - 25 16 6
    35 - 17 12 5
    36 - 12 7 5
    37 - 7 6 1
    38 - 4 4 1
    39 - 2 2 0
    40 - 2 1 1
    All - 1189 702 163

    The only real news here is that current pitchers are far more likely to have
    a peak season in
    the latter half of their 30s.  Also, no one is likely to break Kid
    McGill’s record for
    the earliest peak ever.

    Let’s ask another question: Using the info available in the Neyer/James
    Guide to Pitchers, how do fastballers age compared to other groups of pitchers?  Since
    liveballers age so
    much differently than dead-heads or box’rs, let’s just look at liveballers
    born before the
    60s to start with.  The results (in parenthesis is the number of pitchers in
    each group):

    Fast Junk
    Age (360) (232) Fast Junk
    18 1 0.3 16-19 0.5 0.2
    19 4 2 20-24 17.5 11.9
    20 9 6 25-29 42.1 39.6
    21 25 13 30-34 29.4 31.9
    22 34 25 35-39 8.9 13.5
    23 51 40 40+ 1.3 2.9
    24 74 52
    25 86 78 16-27 43.7 34.4
    26 100 89 28-49 56.3 65.6
    27 97 91
    28 92 99
    29 88 100
    30 83 93
    31 73 79
    32 65 74
    33 58 65
    34 45 58
    35 31 53
    36 26 38
    37 18 28
    38 14 21
    39 9 16
    40 6 11
    41 4 8
    42 3 5
    43 1 3

    What the heck?  This is perhaps the most remarkable breakdown
    yet.  Not only do fastballers peak and prime earlier, and junkballers age
    better, but just look at how both columns go.  In both cases, each group of pitchers get
    better every year until their peak and then get worse every year after it.  Fastballers are
    ahead every year until age 27 and then are behind every year from that point on.

    Let’s break it down by four major pitching groups - fastball, curveball,
    slider, and sinker.  Does one group just warp things or what?

    Fast Curve     Sliders   Sinker
    Age (360)  (109)      (38)  (34)
    19 4 1       0
    20 9 7     0.2 11
    21 25 14       5 23
    22 34 29 15 33
    23 51 42 29 61
    24 74 57 46 61
    25 86 83 75 84
    26 100 94 88 89
    27 97 96 86 83
    28 92 99 84 93
    29 88 100 100 100
    30 83 91 74 84
    31 73 77 58 61
    33 58 64 46 42
    34 45 57 48 35
    35 31 51 36 33
    36 26 31 22 34
    37 18 23 12 20
    38 14 19 6 16
    39 9 10 4 13
    40 6 7 3 7
    41 4 6 5 1
    42 3 2 4 0
    43 1 1 1 0

    A few things - first off, all junkers peak at the same time.  Neat. 
    Curveballers do seem to age the best, but there is a problem - especially with the slider group. 
    Their peak season is unusually peak-arific.  There’s no other season over 90.  That sets off my
    danger detector.  There’s a problem in looking at pitchers as I’m doing here - assigning a year’s
    Win Shares by peak.  Though this system has the benefit of making the results easier to
    quickly read and comprehend to the gentle reader at home, if the peak is excess, it
    artificially deflates all other seasons. Normally this isn’t an issue so I go with it, but with sliders
    it’s an issue.

    Let’s onto a different chart - % of overall value in
    given eras.

    Ages Fast Curve   Slider Sinker
    16-19 4.7 1.3 0.05 0
    20-24 17.5 13.2 10.4 17.8
    25-29 42.1 41.9 47.3 42.6
    30-34 29.4 31.6 32.2 27.9
    35-39 8.9 11.9 8.7 11.0
    40+ 1.3 1.4 1.4 0.7

    Curvers seemed to age better, but for a while at least sliders aged the
    best.  In general, these confirms that no single group distorts the picture.  Fastballers can’t
    blame their poor comparison on knucklers or grandfathered-in spitballers, or just one group
    of junkers. The best they can claim here is a slight lead over sinkers in the early 30s,
    and a barely-there lead over sliders in their late 30s.  Yippee.

    That breakdown is so clear, you can pretty much assume that you will see
    something
    similar for the 1960s guys.  Let’s check anyway.  And
    since I got them,
    let’s look at the guy born from 1970-4 as well.  Here it is:

            1960s   1970-4
    Fast Junk Fast Junk
    Age (111) (33) (38) (11)
    19 0.4 1 0 0
    20 4 7 2 3
    21 12 15 8 16
    22 32 31 19 35
    23 57 48 45 52
    24 70 71 63 80
    25 98 100 84 85
    26 97 73 91 100
    27 90 66 100 80
    28 94 91 88 79
    29 100 90 70 63
    30 87 71 62 50
    31 83 57
    32 71 58 Ages Fast Junk
    33 58 36 16-9 0 0
    34 53 24 20-24 18.5 25.2
    35 45 31 25-9 58.6 55.2
    30+ 22.9 19.6

    Fast Junk
    16-9 0.04 0.1
    20-4 15.2 18.8
    25-9 41.8 45.7
    30-4 30.8 26.9
    35+ 12.2 8.5

    So, just to confirm, the clearest and most consistent aging
    pattern split that I’ve come across for liveball pitchers, just completely stopped, came to an
    end, and totally reversed itself, oh, about 20 years ago or so.  Sure, why not.  Now junkers
    get up to speed quicker, peak and primer earlier, and age worse.  Makes perfect sense?

    OK, maybe there’s a simple solution.  That liveballer cluster covers a lot
    of years.  Maybe it began as wildly pro-speedballers in way back in the days of Ruth and has
    gradually shifted.  OK, I like that theory.  Let’s check on the pitchers born in the
    1950s and 1940s as separate groups.  Maybe, hopefully, they’ll show a similar pattern to the
    1960s.

    1950s 1940s
    Ages Fast Junk Ages Fast   Junk
    16-9 0.1 0.2 16-9 0.8 0.5
    20-4 20.6 17.5 20-4 21.6 18.7
    25-9 45.3 44.4 25-9 43.8 38.8
    30-4 26.7 27.5 30-4 23.9 25.8
    35-9 6.7 9.0 35-9 7.8 12.1
    40+ 0.6 1.4 40+ 2.1 4.1
    Prime 24-8 25-9 Prime 24-8   25-9
    Peak 26 25 Peak 26 29

    Not what I wanted to see.  It’s the same pattern that persisted throughout the liveball era.  Yes, junkers had an earlier

    peak by one year in the 1950s, but look at all the other info.  The early peak looks like a fluke.  Whatever
    happened to the 1960s/70s pitchers, it came out of nowhere.

    Let’s go backwards now.  Maybe I can find some clues if I look at
    deadballers and pitchers box guys.  Here they are:

    Deadballers pre 1893
    Ages Fast Junk Ages Fast   Junk
    16-9 1.1 0.2 16-9 3.2 2.5
    20-4 26.5 20.2 20-4 42.7 37.1
    25-9 44.3 49.6 25-9 36.1 45.9
    30-4 20.3 25.6 30-4 15.5 13.6
    35-9 5.9 4.0 35+ 2.6 0.9
    40+ 1.8 0.4 Prime 21-5   23-7
    Prime 24-8 25-9 Peak 23 27
    Peak 25 27

    Well, this looks a little familiar.  Fastballers do better early?  Check. 
    Earlier prime?
    Check.  Earlier peak?  Check.  Do they do worse after age 30?  Well, it gets
    a little
    confusing here, but the fastballers are doing worse in their early 30s in the
    deadball era.  So
    in the first phase of decline they’re still worse.  As for the box’rs, what
    you have to
    remember is just how wildly early these guys as a whole peaked.  Remember
    they were
    declining in their late 20s, and again in the first phase of their decline,
    fastballers are doing
    poorly.

    So just to recap - from 1876 to the 1980s baseball went many changes - the
    pitchers were
    moved back twice, given a mound, lost the spitball and shineball, had
    several eras of high-
    scoring offense, and low-scoring deadness.  It survived two world wars and
    other, smaller
    conflicts.  It integrated, adopted night baseball, conquered the minor
    leagues, went to
    airline travel, coast-to-coast leagues, and paid grown men to put on silly
    looking costumes
    and serve as mascots.  Yet throughout all this turmoil, one consistent held
    true: fastballers
    started earlier, got up to speed quicker, entered their prime earlier,
    peaked earlier, and -
    through at least the first stages of decline - performed considerably worse
    than junkers.

    Then came the 1980s.  Now absolutely none of that is true.  The exact
    opposite is going
    on.  Sure.  OK.  Why not?  What the hell.

    Ideas?  Explanations?  I’m empty folks.  Not a clue.  I can throw a few
    things out - the
    1980s is associated with the rise of the split-fingered fastball.  Does that
    have something
    to do with it?  I dunno.  Pitch counts?  (shrugs).  Maybe.  You know what
    though?  None
    of these really explains it because there are two separate things going on -
    not only are
    fastballers aging better, but everyone else is aging worse.  How the heck
    does the rise of
    the splitter cause curveballers to pitch worse at age 34?  It’s the
    damnedest thing.

    So much for that one.  Next question—what happens when you compare how
    righties and
    southpaws age?  First, let’s look at liveballers born before 1960:

    RIGHTYS VS. LEFTYS
    R L R L
    19 3 3 0.3% 0.3%
    20 8 9 0.7% 0.8%
    21 21 20 1.8% 1.9%
    22 32 32 2.7% 3.0%
    23 52 44 4.3% 4.1%
    24 72 60 6.1% 5.6%
    25 91 76 7.6% 7.1%
    26 99.5 100 8.3% 9.4%
    27 99.9 92 8.4% 8.6%
    28 100 88 8.4% 8.3%
    29 99 88 8.3% 8.2%
    30 93 84 7.8% 7.8%
    31 87 73 7.3% 6.8%
    32 71 68 5.9% 6.4%
    33 64 57 5.4% 5.3%
    34 54 48 4.5% 4.5%
    35 43 36 3.6% 3.4%
    36 32 29 2.7% 2.8%
    37 23 20 1.9% 1.9%
    38 17 16 1.4% 1.5%
    39 13 10 1.1% 0.9%
    40 9 6 0.8% 0.6%
    41 6 4 0.5% 0.4%
    42 4 3 0.3% 0.3%
    43 2 1 0.2% 0.1%

    This is one instance where the peak seasons distort the comparison.  The
    lefties had one
    big year with only one other season (barely) worth 90% of it.  The righties
    had their top
    four seasons within 1% of their value.  Maybe there’s a reason why one group
    has such a
    cluster of peak seasons and the other doesn’t, but I’m not assume that’s the
    case.  As
    mentioned earlier, at times the distribution of win shares within the prime
    is a bit fluky.

    That’s why I have the second series of columns on the right.  That’s what
    percentage of
    the pitchers’ total win shares were accumulated during that one season.  The
    lefties gained
    a considerably greater percentage in their best season than the righties
    ever did, and that
    skews that data in the left columns.  According to those columns, the
    righties smoke the
    lefties in terms of aging.  Looking at the columns on the right, it’s quite
    a bit closer.
    Looking at it another way:

    Liveballers
    Ages R L
    16-19 0.3% 0.3%
    20-24 15.5% 15.5%
    25-29 41.0% 41.5%
    30-34 30.9% 31.1%
    35-39 10.7% 10.4%
    40+ 2.1% 1.5%

    16-27 40.2% 40.8%
    28-49 59.8% 59.2%

    A very modest, and probably insignificant lead for righties.  They have less
    an advantage
    of less than 1%.

    Has this always been true?  Let’s look at deadballers, and then pitchers box
    guys:

    Lefties - Deadball
    R L
    19 6 3
    20 15 21
    21 26 25
    22 45 55
    23 58 73
    24 79 89
    25 97 87
    26 97 99
    27 100 100
    28 99 87
    29 87 72
    30 73 58
    31 60 38
    32 48 27
    33 37 19
    34 25 17
    35 17 12
    36 12 9
    37 9 4
    38 7 2
    39 3 5
    40 4 3
    41 3 1
    42 2 0
    43 1 0

    Deadballers
    Ages R L
    16-19 0.8% 0.3%
    20-24 22.1% 29.0%
    25-29 47.5% 49.0%
    30-34 24.0% 17.6%
    35-39 4.7% 3.5%
    40+ 0.6% 1.5%

    16-27 51.9% 60.9%
    28-49 48.1% 39.1%

    Box R L
    16-29 85.0% 92.2%
    30+ 15.0% 7.8

    Well that’s interesting.  Clearly before the liveball era lefties aged
    worse, and not just bit a
    little bit worse.  They began falling apart as soon as they passed their
    peak and generally
    aged a year or two worse than righties.  And this was true for the entire
    half-century of
    ball back then.

    So if that’s the case, are modern lefties and righties aging the same or has
    the balance
    slowing been tipping toward lefties?  Let’s look at the 1960s and 1950s
    pitchers:

    1960s
    Age R L
    16-9 0.2 0.1
    20-4 16.4 14.8
    25-9 42.4 39.0
    30-4 31.0 28.6
    35+ 9.9 17.5
    Peak 25 26
    Prime 25-9 26-30

    1950s
    Age R L
    16-9 0.1 0.3
    20-4 19.9 22.4
    25-9 44.0 45.1
    30-4 26.6 25.9
    35-9 8.3 6.0
    40+ 1.1 0.3
    Peak 26 26
    Prime 25-9 25-9

    1940s
    Age R L
    16-19 0.8 0.3
    20-24 22.3 17.8
    25-29 43.2 38.2
    30-34 22.3 30.7
    35-39 8.5 10.8
    40+ 2.8 2.3

    Some conflicting data here.  The 1960s lefties are smoking the righties,
    especially in old
    age. Take a bow Jaime Moyer, Chuck Finley, David Wells and Randy Johnson.  A
    similar
    trend occurs in the 1940s bunch.  Though righties did better after turning
    40, they were
    torched in the previous ten years.  Meanwhile there’s the 1950s, where there
    is little
    difference at all, but a minimal edge to righties during the decline years.

    What to make of this?  Lacking the desire to sort through every decade of
    pitchers, here’s
    my theory: throughout the deadball era righties (obviously) aged better, but
    this trend
    slowly reversed itself.  At first, righties likely had a small edge. 
    Actually, given the above
    charts on pitchers since 1940 and combining it with the overall liveball
    info, righties must
    have aged better in the initial decades of the liveball era.  For whatever
    reason - I’ll try to
    take some guesses later - this has flipped over.  So why were the 1950s
    backwards?  They
    don’t fit the trend.  I have no idea, but keep in mind the sample size for
    one decade isn’t as
    large - especially if you’re only looking at lefties born each decade. 
    Maybe it just a dry
    spell for lefthanded pitchers.  It could be as simple as that?

    OK, so why have lefties improved their aging patterns?  One theory came to
    me as I
    looked at the 1960s lefties: call it the Terry Mulholland Theory.  As anyone
    who has seen
    baseball in recent years can attest, teams often like having a lefty in the
    ‘pen.  Some, like
    Jesse Orosco, can seemingly pitch forever as a LOOGY if they can exhibit
    some minimal
    control.

    That’s a theory, but I don’t buy it.  Sure LOOGYs are prolific, but there
    ain’t many that
    are this study.  Captain LOOGY himself, Orosco, fell 96 starts shy of making
    it.  There are
    some starters-turned-relievers in the study - Mulholland, Rheal Cormier,
    Chris Hammond,
    Jeff Fassero,  and Kent Mercker are the big ones from the 1960s - but not
    many.  The
    previously mentioned guys are about it for that decade.  And their
    contributions pale in
    comparison to Glavine, Johnson, Wells, Moyer, & Rogers.  Besides, their
    contributions
    are largely matched by that of righty converted starters like John Smoltz,
    Flash Gordon,
    and Cal Eldred.  Lefties do have some advantage there, but not enough to
    explain the bid
    difference in the 1960s group.

    So what is it?  Damned if I know.  That’s my own good theory.  I wish I had
    a brilliant
    answer right about now, but I don’t.  Ah well - let’s ask another question: 
    What about
    knucklers?  Do they age the same?  They have a reputation as late bloomers. 
    Let’s check
    it out - comparing pitchers listed as primarily knucklers in the Neyer/James
    Guide to my
    main sample of liveballers:

        KNUCKLE     LIVE
    20 0 8
    21 3 21
    22 15 32
    23 35 50
    24 56 69
    25 76 86
    26 72 100
    27 49 98
    28 80 97
    29 89 96
    30 100 79
    31 92 70
    32 99 57
    33 77 48
    34 88 39
    35 75 31
    36 67 23
    37 51 16
    38 42 12
    39 42 8
    40 31 6
    41 18 4
    42 15 2
    43 13 1
    44 7 1

    Knucklers have the latest prime (ages 28-32) of any group that I’ve isolated
    almost without exception.  Pitchers who got their first real chance at age 29 or
    later had a later
    prime, but that’s in.  Pitchers who got started at age 28 had the prime
    (I’ll discuss this
    stuff more later on), and that’s a group which by definition should have had
    a late start.
    Nothing terribly surprising, but it’s nice to have the data.

    Well, that’s knucklers, what about spitballers?  There’s another group that
    should age
    better.  This is a bit more confusing, because most were deadballers, but
    there are also some
    grandfathered-in guys.  Since live and deadball eras had such different
    aging patterns I’ll
    compare grandfathered guys (referred to people as “Last”) to liveballers,
    and deadball
    spitters (D.Spit below) to other deadballers.  Making it even more confusing
    is Jack
    Quinn, who pitched most of his career in the liveball era, but pitched more
    innings in the
    deadball era than most of the deadballers in this study.  I’m actually going
    to include him
    in both groups for now.  Here are the results:

    Age Last Live D.Spit Oth.Dead
    20 0 8 0 19
    21 8 21 11 28
    22 20 32 22 51 Ages D-Spit noQuinn
    23 37 50 39 65 16-9   0% 0
    24 47 69 49 85 20-4   14.3 15.4
    25 73 86 71 97 25-9   49.2 52.2
    26 92 100 77 100 30-4   27.6 28.5
    27 100 98 100 98 35-9   5.6 3.6
    28 72 97 85 95 40+ 3.3 0.3
    29 78 96 81 82
    30 81 79 73 68 Dead - Others
    31 71 70 68 51 16-9 0.8%
    32 67 57 45 42 20-4 24.9
    33 48 48 23 34 25-9 47.2
    34 37 39 23 22 30-4 21.7
    35 42 32 22 15 35-9 4.5
    36 39 23 15 11 40+ 0.9
    37 21 17 5 9
    38 16 12 4 6 Last Live
    39 17 8 4 4 30-4 26.0 31.0
    40 17 6 6 4 35+ 22.0 12.3
    41 9 4 2 3
    42 10 2 3 2
    43 9 1 4 0.7
    44 10 1 4 0.2

    Several things - first, no one quite matches the record of knucklers.  These
    guys did age
    better, but not that much better.  Second, please note that the deadball
    spitters have an
    unusually large peak season which artificially depresses all their numbers. 
    If you look at
    the main chart isn’t entirely clear that they aged better than other
    deadballers.  But look at
    the smaller charts on the right.  Deadball spitters had 36.5% of their
    overall value after the
    age of 30.  Other deadballers weigh in at 27.1%.  Considerable advantage to
    the
    unsanitary stylists.  Even if you toss Quinn out it doesn’t change that much
    as his impact is
    almost entirely limited to age 40 and beyond (though his impact is immense
    from that
    point onward).  The grandfathered guys had a much more modest advantage -
    48% of
    their career value after turning 30 instead of 42.3%.  This advantage
    doesn’t really appear
    until after age 35.

    This helps solve the riddle of 1890s pitchers.  This was the gang that aged
    so well in their
    late 30s despite having no WWII impact.  Well, this spitter split does prove
    that the
    grandfathered guys born in the McKinley era did boost the overall aging
    patterns.

    Well, spitters age better.  No big surprise there, but again, it’s always
    nice to have the
    data.  Any thing else worth checking?  Well, how about walk rates and
    strikeout rates?
    Do pitchers with better K-rates age better?  Do pitchers with better control
    age better?
    And how do flamethrowers compare to control masters in terms of aging?

    Fortunately, due to the thankless yeomen work of Dr. Memory, this is pretty
    easy to
    answer.  He, for whatever masochistic reasons of his own, went through the
    statistical
    record and adjusted the K-rates, W-rates, and K/W ratios for every pitcher
    in this study
    for their leagues’ rates With these league-normalized numbers, it’s easy to
    compare
    pitchers across eras.

    Again, let’s look at the main sampling of liveballers born before 1960 and
    see what
    happens.  For this, I’ve divided up all pitchers into 10 groups - from the
    best strikeout
    pitchers, to the worst strikeout pitchers, and the same with adjusted BB
    rate.  Let’s look
    at the results, starting with K-rates.  The info at the end is average
    career Win Shares per
    pitcher in the group, and at the very end the Dr. Memory K #s of the
    pitchers in each
    group:

    Adj. K-rate
    Grp   16-9 20-4 25-9 30-4 35-9 40+ Peak Prime Avg K#
    A 0.7 15.2 38.5 29.5 13.5 2.7 27 26-30 160.8 124+
    B 0.3 20.0 40.4 27.7 10.4 0.9 26 25-29 120.7 113-23
    C 0.4 20.1 41.0 29.6 7.9 1.0 29 25-29 128.1 107-12
    D 0.5 15.3 39.8 31.4 9.9 2.9 29 26-30 120.0 101-06
    E 0.3 15.5 42.9 29.7 9.6 2.0 26 26-30 120.5 95-100
    F 0.4 13.9 41.1 30.0 11.2 3.4 27 26-30 103.8 90-94
    G 0.4 21.9 42.1 27.9 6.6 1.1 25 25-29 99.1 86-9
    H 0.4 11.3 44.2 34.8 9.1 0.6 29 26-30 91.5 80-5
    I 0 12.5 39.7 31.6 14.0 2.2 26 26-30 104.3 73-9
    J 0.1 17.0 46.5 28.2 8.1 0.2 28 25-29 83.5 72-

    First off, it does appear that being a great strikeout pitcher comes in
    handy when aging,
    but not nearly as handy as I would have guessed.  Group A had 45.7% of their
    value after
    age 30, which is definitely above-average as half the groups had less than
    42% of their
    value from that point onward.  They are not, surprisingly, the best aging
    group.  That
    honor goes to, shockingly, the Group I, who has 47.8% of their value after
    age 30.  The
    runner up group is far closer to the fifth best aging group than to them.

    This I find very surprising because in the New Historical Abstract Bill
    James shows that
    the best indicator of future value for a young pitcher is his K-rate.  He
    mentions that the
    last young right-handed pitcher with a consistently poor K-rate who ended up
    having a
    good career was Lew Burdette almost a half-century ago.  So why the
    difference here?

    Simple - we’re looking at career K-rates, not just those of young’uns. 
    Almost everyone
    has their K-rate go down as they get older, and so career K-rates really
    aren’t a great
    measure of a pitcher’s ability to age well.  In fact, though Group A has the
    2nd best aging
    pattern, groups B and C have some of the worst aging patterns.  Both of
    those groups
    used up over 60% of their value by the time they reached 30 years of age.

    There is still some evidence here to bolster the importance of K-rates Group
    J, for
    example, has one of the worst aging patterns.  They’re the worst after age
    40, and 2nd
    worst to K-rate group G after age 30.  The results are decidedly mixed,
    though.

    How about walk rates?

    Adj BB-rate
    Grp 16-9 20-4 25-9 30-4 35-9 40+ Peak Prime Avg BB#
    A 0.1 13.4 39.1 31.9 12.8 2.7 30 26-30 144.7 144+
    B 0.7 14.2 38.4 31.1 13.0 2.6 28 26-30 148.0 130-43
    C 0.05 17.6 36.3 29.9 13.8 2.2 26 25-29 137.0 121-9
    D 0.8 11.6 43.4 34.1 8.7 1.4 29 26-30 120.0 115-20
    E 0.1 12.0 36.5 34.7 13.9 2.8 30 26-30 121.1 108-14
    F 0.2 14.4 39.9 31.0 12.3 2.3 29 26-30 105.6 103-7
    G 0.2 15.4 43.2 31.9 8.7 0.5 27 26-30 113.8 98-102
    H 1.0 19.7 50.5 24.2 4.1 0.5 26 25-29 86.1 92-7
    I 0.2 20.5 42.9 28.1 7.1 1.2 26 25-29 84.8 82-91
    J 0.05 23.5 50.5 20.1 4.0 2.0 27 25-29 67.5 81-

    The first thing I notice is how much better the BB#s are in comparison to
    the K#s.  They
    don’t fall below 100 until group G here, while they fell below with Group E
    up above.
    These pitchers on the whole had better control than strikeouts. 
    Interesting.

    What’s even more important here is that career W rate seems to have a
    clearer impact on
    aging patterns than K-rates do.  Group A has the 2nd best aging pattern
    (which I’m
    arbitrarily defining as what percentage of their overall value did they get
    after age 30).  So
    far that’s just like the K-rates, but here Group B has the 3rd best aging
    pattern.  Group C
    has the 4th best aging pattern.  The groups with 6 best BB numbers have the
    6 best aging
    patterns.  The three worst aging patterns were (by far) the three bottom
    groups.  There’s
    also a broader range.  In the K rates, the group with the greatest overall
    value after age 30
    was at 45.7%.  Here, four groups best that mark and a fifth comes in at
    45.6%.  The
    lowest amount of post-30 value with the K-rates was 35.6%.  Here, there are
    two groups
    (H and J) under 30%.

    The best aging group here, if you’re wondering, is Group E at 51.4%.  I have
    no idea why
    they lead, but there it is.  Group J came in dead last, with barely a
    quarter of their value
    coming after turning 30.

    One other thing comes out in this: ages 26-9 clearly are the main prime
    years for
    liveballers.  Despite the fact there is such a notable difference in aging
    patterns, the prime
    years are almost the same for all.  Some begin their prime a year earlier
    than others, that’s
    the only difference.

    Whadaya say we compare K-rates to W-rates?  I’ve got the chart figured out,
    but really, it
    doesn’t add anything.  It’ll just repeat what I just said.  Instead, let’s
    move on to the last
    of the Dr. Memory info: what impact does a K/W ratio have on a pitcher’s
    aging pattern?

    Adj K/BB-ratio
    Grp 16-9 20-4 25-9 30-4 35-9 40+ Peak Prime Avg K/BB#
    A 0.8 13.8 35.9 31.3 14.8 3.4 30 26-30 188.8 139+
    B 0.1 12.2 36.7 33.4 14.2 3.5 26 25-29 151.4 125-38
    C 0.7 19.0 40.4 29.9 8.9 1.1 29 26-30 139.9 115-24
    D 0.2 1.8 42.0 30.8 12.3 2.9 26 26-30 132.3 107-14
    E 0.1 18.1 41.5 30.8 8.3 1.1 29 25-29 104.9 101-6
    F 0.3 14.2 42.9 32.1 9.6 0.9 28 26-30 100.7 95-100
    G 0.4 16.9 46.6 28.8 7.2 0.2 26 25-29 94.3 91-4
    H 0.1 17.4 43.5 30.5 7.0 1.5 26 25-29 93.0 84-90
    I 0 19.9 43.7 25.7 9.6 1.0 26 24-28 69.5 77-83
    J 0.1 19.5 51.1 25.2 4.2 0 26 25-29 53.8 76-

    From the Dept. of Not At All Surprising Info: better pitchers tend to have
    better K/BB
    ratios.  It’s perfect the way it works out—the best K/BB group has best
    average win
    shares, group B in second and so on down the line to group J with the worst
    average.  The
    most interesting thing to me is that the better the group of pitchers, the
    later the prime.
    It’s not perfect as Group B had an earlier prime than C, D, and F while
    averaging more
    win shares per pitcher, but that’s the only major exception.  Pitchers with
    a lousy ratio,
    when they start declining and losing a little of what they had, aren’t long
    for this game.
    Guys in Group J get barely more of their value after age 35 than Groups A
    and B get at
    after age 40.

    Another question: what about when guys first make their mark in the
    baseball?  Do guys
    who come to the bigs at an early age have the same aging pattern as guys who
    come in
    later?  For this study, I’m not looking at how old a pitcher was when he
    first arrived in
    MLB but how old he was when he first earned 3 win shares in a season. 
    There’s just too
    many guys who came up for a cup of coffee and then didn’t come back for
    another year or
    three.  This has been an old story from Joe Nuxhall to Mike Morgan.  By
    making it three
    win shares instead I’m looking at how old they were when they first got
    themselves
    somewhat established.  The first group is 19 or younger (19-) and the last
    group is 29+;
    every other group is just one age.  Here’s the results (again looking at
    liveballers born
    before 7/1/59):

    First Year with 3 Win Shares
    Age 19- 20 21 22 23 24 25 26 27 28 29+
    18 9 1 0.4 0.1 0.2 0 0 0 0 0 0
    19 56 2 0.3 0.1 0 0 0 0 0 0.4 0
    20 66 57 4 0.4 0.5 0.2 0 0 0 0 0
    21 78 77 76 3 1 0.5 0.2 0.3 0.3 0 0.3
    22 84 74 72 73 4 1 0.2 1 0 0.4 0
    23 80 72 88 88 67 4 1 0.4 0 1 0
    24 88 94 98 100 79 87 4 2 0 0.4 1
    25 82 100 99 99 91 96 82 3 2 1 1
    26 87 76 100 94 100 100 100 92 2 1 0.3
    27 100 82 91 82 85 91 96 99 76 7 4
    28 89 71 77 80 82 85 86 99 90 100 1
    29 73 73 64 75 83 86 91 100 100 89 43
    30 66 64 54 67 66 88 90 98 99 97 68
    31 47 46 49 56 54 76 75 91 99.7 97 82
    32 37 52 44 52 52 61 67 72 94 74 86
    33 28 43 38 44 44 53 64 56 87 76 100
    34 29 34 34 35 38 40 45 49 82 73 94
    35 20 22 26 27 28 40 38 36 40 57 78
    36 18 15 20 18 24 22 31 31 40 52 60
    37 7 13 15 13 14 12 26 17 30 40 49
    38 8 6 12 7 12 5 18 15 20 32 48
    39 1 3 9 8 6 1 18 11 11 19 36

    Comments time: The 19- pitchers averaged more win shares than any other
    group, which
    makes sense.  The best players should be the first to make it to the majors.
      However,
    looking at it here, they aged the worst from age 32-onward of any group
    here.  That’s
    interesting.  This doesn’t surprise me much.  One of the favorite lists I
    ever cooked up was
    a list of liveballers who won 150 games before they turned 30.  Only one -
    Greg Maddux -
    made it to 300.  The others either: 1) had their arms fall off in their
    early 30s (Drysdale,
    Ferrell, Newhouser, Hunter, Holtzman), or 2) survived, but weren’t nearly as
    good as they
    had been when they were young (Feller, Harder, Blue, Gooden).  They had 52
    20-win
    seasons before age 30, but only 4 afterwards, and 3 of those were Jim
    Palmer.  The point:
    pitchers that were worked the hardest when they were youngest don’t hold up
    the best
    when they age.  That’s exactly what happened here.

    Another interesting result is that the peak often occurs at the same dang
    time.  One
    question I had going in was would pitchers that came up later have the same
    aging curve
    as others, just begun later?  In other words, would it take most of these
    groups the
    amount of time to reach their peak and prime?  I don’t see that happening in
    these results.
    Those that first established themselves from ages 20-25 peaked at about the
    same time -
    age 25 or 26.  Only the age 22 pitchers missed out on that.  Five of the
    first six groups all
    had their prime at either ages 23-7 or 24-8 (age 23 had their prime from
    25-9).  There are,
    obviously some differences, as guys who came up at age 28 peaked later than
    guys who
    came up at age 20, but whereas the early arrivals had a couple years to work
    up to their
    peak, the later arrivals often began in their peak.  Ages 24-8 all began
    their prime either
    their first big year or the year after while only one of the earlier groups
    could say that.

    It’s also interesting to compare the latter groups to knuckleball pitchers. 
    Knucklers aged
    better than just about all of them.  Comparing their aging patterns to
    Groups 19- to 28
    (I’ll look at the 29+rs separately in a second) knucklers score the best at
    every age after
    turning 30 except age 31, where they finish third, and age 33, where they
    come in second.
    Every other year they best every last one of those groups.  That’s
    impressive.  Comparing
    them to the 29+ group, they don’t do quite as well, but they still do age
    better.  Here’s
    comparing those two groups from age 30-9:

    Age Knuck 29+
    30 100 68
    31 92 82
    32 99 86
    33 77 100
    34 88 94
    35 75 78
    36 67 60
    37 51 49
    38 42 48
    39 42 36

    The 29+rs had the lead in the heart of their prime (33-35) and a narrow lead
    at age 38, but
    that’s it.  If anyone should age really good, it’s guys who had accomplished
    nothing in
    MLB by age 29 yet still managed to start games.  Yet knucklers aged a little
    better.  This
    is despite the fact that there are several knucklers in the age 29+ group,
    including at least
    3 pitchers who had no career win shares before their age 30 season.

    One last bit I want to check.  I’ve ignored everyone born after 6/30/69 here
    so far, and
    there are numerous guys from the first half of the 1970’s who have 100
    starts and have
    finished what should be their prime.  Let’s see how their aging.  For
    comparison I’ll line
    up their numbers against 1960s pitchers.

    1970-4 Pitchers (58 pitchers)
    Age   70-4 60s
    19 0 2
    20 2 7
    21 12 14
    22 24 33
    23 51 57
    24 67 73
    25 86 100
    26 93 97
    27 100 90
    28 97 96
    29 84 97
    30 71 88

    I need to note that there are pitchers out there born from 1970-4 who
    haven’t yet started
    100 games but will end up doing so before their done, so those numbers
    aren’t in stone.
    Obviously, the second half of the decade still has to go through the prime. 
    As it stands,
    they’re on track for the oldest peak season for any decade group since the
    1920s, and the
    worst age 30 season of the liveball era.  Again, this should change as some
    late bloomers
    emerge.

     

    Chris Jaffe Posted: September 02, 2005 at 02:11 PM | 11 comment(s) Login to Bookmark
      Related News:

    Reader Comments and Retorts

    Go to end of page

    Statements posted here are those of our readers and do not represent the BaseballThinkFactory. Names are provided by the poster and are not verified. We ask that posters follow our submission policy. Please report any inappropriate comments.

       1. Ivan Grushenko of Hong Kong Posted: September 02, 2005 at 06:11 PM (#1593509)

    This is very interesting and obviously reflects a lot of work.  What implications do you see for teams today?

    1)  Draft young fastballers and let them go via FA?
    2)  Draft HS fastballers in the mid rounds?
    3)  Sign old junkballers as FA?
    4)  Trade productive young starters at age 27?

    Which teams do you think most profit from these implications?  How do you think these conclusions translate to the minor leagues or to relief pitchers?

       2. Tango Tiger Posted: September 02, 2005 at 06:15 PM (#1593520)

    Chris,

    A few minor points.  (Too much material to read in one sitting)

    Your “aging” patterns is not really an aging pattern.  I would guess that you would have gotten similar results if you simply used IP.  What your data is telling you is how many pitchers at each age class are pitching.  When you have things like expansion, it’s easy to see that this opens up the door for the older guys to stay in the game.  To do a true aging pattern, you need to have the same pitchers at the same weights in two or more age classes (which by itself will bring selective sampling issues).

    Technical notes: to sort in Excel by row, click data/sort, and select “options”.  Toggle your orientation as you need it.  Your other choice is to cut/PasteSpecial, and select “transpose”.  This turns rows into cols and cols into rows.

    Did you actually go through each pitcher in the (excellent) James/Neyer guide manually, and noted his pitch type style?  This is one of those times that I wished the book came with a CD.  I’d love to get that file from you, if you can.

    Tom

       3. studes Posted: September 02, 2005 at 06:34 PM (#1593546)

    Looks great.  I’m going to have to print it out to read, but I can’t print.  Are Primer articles set up so that they won’t configure to a printer somehow?  Just call me clueless…

       4. studes Posted: September 02, 2005 at 06:36 PM (#1593553)

    Never mind.  Apparently I had a problem with Mozilla—it prints from Explorer.

       5. Derrick Jensen Posted: September 02, 2005 at 06:44 PM (#1593562)

    Hey Chris,

    This is phenomenal, one of the best articles I’ve read on this site, if not the best.

    Thank you,

    Derrick

       6. Dag Nabbit is part of the zombie horde Posted: September 02, 2005 at 08:23 PM (#1593751)

    Sorry about some of the columns being off. 

    Technical notes: to sort in Excel by row, click data/sort, and select “options”. Toggle your orientation as you need it. Your other choice is to cut/PasteSpecial, and select “transpose”. This turns rows into cols and cols into rows.

    I’ll check that out.

    Did you actually go through each pitcher in the (excellent) James/Neyer guide manually, and noted his pitch type style?

    When possible, yea.  Some weren’t listed, some had no clear #1 pitch. 

    This is one of those times that I wished the book came with a CD. I’d love to get that file from you, if you can.

    Check your e-mail.  If anyone else wants the database, just e-mail me and I’ll send it to you when I get the chance (note: may not be done right away).

    What implications do you see for teams today?

    Well, that’s a trickier one.  Any implications taken from this would have a giant qualifier on it - just because it’s some sort of trend doesn’t mean its true for all pitchers. 

    Derrick - thanks for your kind words.

    A few notes . . . some of the conclusions differ from what I said in Toronto.  There, I was struck by how close the 1890s and 1960s were - in part because I never looked at spitters.  In whipping this article up it seemed clearer that 1960s-born pitchers are retaining more value later. 

    Really, in some ways the real story are the 1930s/40s/50s/ guys.  They’re the great step backwards.  Deadballers age better than box’rs.  Early live ballers age better than deadballers.  Current age better than early liveballers, but the mid-live ballers were the only major step backwards. 

    Also, the bit at the end in comparing knucklers to late arrvials comes from a talk I had with Dial.  He wondered how much of knucklers aging was simply due to their getting a later start than most.

       7. Walt Davis Posted: September 03, 2005 at 02:29 PM (#1595195)

    Haven’t read the whole thing yet.  And sorry if I missed you addressing this point.

    Generally you’re measuring aging patterns as % of peak.  This would seem to guarantee that pitchers who pitch during a transition in starter usage will “age poorly”.  For example, the young guys starting in the 60s/70s (roughly 1945-1955 birthdates) were making 35-38 starts a year, then baseball transitioned to the 4.5-5 man rotation and these guys were making 31-34 starts a year later in their careers (of those who had late careers).  Four fewer starts a year means a lot fewer win shares.

    To take one example, Rick Reuschel (born May 1949) made 37-38 starts almost every year through age 31.  In 74, he made 38 (and 3 relief appearances god love him) which was only 6th in the league.  Late in his career, he was making 32 to 36 starts a year, but he tied for the league lead with those 36.  Reuschel, one of the best-aging pitchers of his generation, did as much in his late career as most of today’s best old pitchers (158, 131, and 116 ERA+s at ages 36, 38, and 40 and always 200+ IP).  But he, and every other starter in baseball, was making 10% fewer starts and pitching about 15% fewer innings than he did in his prime.  He aged better than Tom Glavine, probably Maddux, and maybe even nearly as well as Clemens (given Reuschel’s lower talent level to begin with), but he may look worse compared to peak just because pitcher usage changed.

    Put most simply, in raw win shares, pitchers of earlier eras had much higher peaks than today’s.  They could have posted the same number of late-career win shares in the same number of starts as today’s pitchers, but measured against their own higher peak, they would appear to be much worse.  That wouldn’t appear to be enough to explain the whole difference, but some.

    Not sure there’s an easy solution.  You could look at raw win shares.  Or you could try to normalize in some way—maybe looking at % of win shares to % of innings pitched at each age.

    I think Tango’s comment brushes up against this too.  It’s not clear to me whether you’re getting at different aging patterns or changes in pitcher usage.

       8. Dag Nabbit is part of the zombie horde Posted: September 04, 2005 at 03:42 PM (#1596744)

    For example, the young guys starting in the 60s/70s (roughly 1945-1955 birthdates) were making 35-38 starts a year, then baseball transitioned to the 4.5-5 man rotation and these guys were making 31-34 starts a year later in their careers (of those who had late careers). Four fewer starts a year means a lot fewer win shares.

    Yea, but those guys were part of a 30 year swath where pitchers kept aging like that.  I don’t think there was a continual 30 year revolution in pitcher usage.

    Your larger point stands that changes in usage would influence this.

       9. Catfish326 Posted: September 06, 2005 at 03:16 PM (#1599865)

    Uh, some (many?) current pitchers have the benefit of performance enhancement drugs.  Just as the likes of Bonds shattered 100 years of aging statistical data, we see similar, goofy aging trends for contemporary pitchers.  The answer swirls in the juice.

       10. Slinger Francisco Barrios (Dr. Memory) Posted: September 13, 2005 at 06:59 PM (#1615666)

    The answer swirls in the juice.

    First, Catfish, you have to know if you even have a question the juice can answer.

       11. Greg Pope thinks the Cubs are reeking havoc Posted: September 20, 2005 at 07:40 PM (#1630508)

    Then came the 1980s. Now absolutely none of that is true. The exact opposite is going on. Sure. OK. Why not? What the hell.

    I think that you switched from birth decade to pitching decade somewhere around this quote, but I couldn’t tell when.  Did the effect start happening in the 1980s or did it start affecting pitchers born in the 1980s?

    You must be Registered and Logged In to post comments.

     

     

    << Back to main

    BBTF Partner

    Support BBTF

    donate

    Thanks to
    Mike Emeigh
    for his generous support.

    Bookmarks

    You must be logged in to view your Bookmarks.

    Syndicate

    Page rendered in 0.4731 seconds
    47 querie(s) executed