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Wednesday, July 18, 2007

Do pitchers today have it better because of medicine and technology?

By Tangotiger, 12:15 PM

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

#1    Chris Miller      (see all posts) 2007/07/18 (Wed) @ 14:16

There’s a couple issues I see.  One is the quality of the league could be part of it.  If the pitcher is being forced to throw with more effort, more often, in order to get people out, that may negate some of the advances in medicine an. 

Second is conditioning, if somebody “practices” a physical activity more often, especially somewhat reduced effort, neurological connections are strengthend, strengthening ligaments, tendons, muscles, and nerves.  The combination of strict pitch counts and 5 day rest periods may have a negative effect on the conditioning of the pitchers.  While we see better conditioning and training practices being used now than ever, many studies have show the best way to strengthen ones self for a specific task, is to train for THAT task.  I believe one of Mazzones teachings is to reduce your velocity, and to throw more often. 

I recommend reading: http://www.dragondoor.com/articler/mode3/69/ or reading Naked Warrior (or any book by) by Pavel Tsatsouline.  His stuff is specific to strength training, but he emphasises that the same principals apply to virtually any physical activity.


#2    Chris Miller      (see all posts) 2007/07/18 (Wed) @ 14:18

What I was getting at about the quality of play, is it’s possible (no data) that pitchers simply throw harder more often, and try to get sharper break, more often than in the past.


#3    MGL      (see all posts) 2007/07/18 (Wed) @ 14:57

First, I don’t get why the “strike zone of the 70’s ate pitchers’ arms up.”

Can someone explain that to me?

Chris’ study fails because of two reasons:  One with such a small sample of pitchers, you really can’t get reliable results, I don’t think.  Two, as many people properly pointed out, when you want to look at similar “anything” in these types of studies, you NEVER want to set a floor near the level of the player or players in question with no ceiling!  That is ridiculous.  All you get are mostly better players with the average player in your sample being much better than the player or players in question.  You want to set a floor and ceiling around the player, such that the average is around your player(s) in question, and close enough so that the ones that are furthest away don’t screw up your analysis, although they generally tend to balance one another out.

Also, it is not that big a deal to get the “comps” right, if you are just trying to figure out the expected IP and decrease in performance (ERA+ or whatever) down the road.  Probably the most important thing is to get a large sample of pitchers.  People are making way too much of this.

Buehrle is a good but not great pitcher and regardless of his track record,
he is probably going to lose 5-10% per year in IP, on the average.  Whether the signing was good or bad depends on a lot of things, not the least of which is your definition of good and bad.

I generally call most FA pitcher signings “bad” for one reason and one reason only.  One, pitchers lose more playing time than batters in years hence, and two, the price per marginal win for pitchers is a lot more than for batters.

I generally don’t comment on how good or bad a pitcher signing is as compared to other pitcher signings, although obviously roughly half are bad and half are good (depending upon how far above or below average constitutes good or bad of course), as compared to the average signing.


#4    Tangotiger      (see all posts) 2007/07/18 (Wed) @ 15:34

MGL: It’s not apparent from your post, but the only reason I quoted Chris was so that I could use the quote as a jumping off point for my own study, which followed.


#5    Tangotiger      (see all posts) 2007/07/18 (Wed) @ 15:44

So as not to confuse the purpose of this blog entry, I removed the link to Chris’s article in the main portion of the blog entry.  For those interested in his article from which I quoted him, here it is:
http://www.baseballthinkfactory.org/files/dialed_in/discussion/landing_buerhle_a_great_move/

You should defer discussion of Buehrle in particular to the Buehrle blog entry here:
http://www.insidethebook.com/ee/index.php/site/comments/buehrle/

The focus of this thread should be on the research I’ve presented, and whatever else you think is related to that.


#6    Tangotiger      (see all posts) 2007/07/18 (Wed) @ 17:20

I added an update to the main blog entry.  Look for:
UPDATE (17:15)


#7    Tangotiger      (see all posts) 2007/07/18 (Wed) @ 18:02

And another update.  Look for 18:00.


#8    Tangotiger      (see all posts) 2007/07/18 (Wed) @ 19:20

And another update.


#9    Rob      (see all posts) 2007/07/18 (Wed) @ 20:19

Would it make sense to look at more pitchers in the post-expansion period?


#10    Guy      (see all posts) 2007/07/18 (Wed) @ 21:19

"However, remember that we really don’t care about the retention rate of BFP, but rather gross BFP.”

I don’t think I agree.  Clearly, the number of IP expected from starting pitchers has changed over time.  If modern usage and medicine allow 33-36 yr-old starters to provide as many IP as 33-36 starters of 50 years ago—despite the fact that todays’ starters in general pitch fewer IP—then that’s a very meaningful change. 

And I don’t think “babying” is a terribly useful analytic label.  Yes, contemporary starters pitch fewer IP.  But their K rates—despite facing a smaller strike zone and better hitters—is pretty strong evidence that they throw much harder in those innings than the starters of yore.


#11    tangotiger      (see all posts) 2007/07/18 (Wed) @ 21:41

Rob/9: The reason I selected 32 pitchers per 8 years (that’s 4 per season) is that it wouldn’t matter if you had 16 teams or 32 teams (or 100) in a league.  A 16-team league would need at least 64 starters, and I only selected the 32 starters with the most PA over that 8-yr time period. 

***

Guy/10: The 25-28 yr olds faced 3800 batters in one era, and 3500 batters in another era.  When those pitchers pitched between the ages of 29-32, they each faced 2700 batters.  The story repeats itself with 29-32 / 33-36 year old matching.

The 25-28 yr olds of today are babied by 300 batters per 4 years.  The reason for that is:
1. they want to protect them, to be able to pitch longer
2. they want to protect them, to be able to pitch more effectively

And yet, when it came time at age 29-32, the babied and non-babied group each pitched the same amount (2700 batters faced over 4 years), and were just as effective.

Why is it such a great thing that they were able to have a higher retention rate?  I mean, they could baby them further, and make them only face 3000 batters at the top end workhorse 10 years from now, and still we will find they will face 2700 batters at age 39-32.

***

The burnout protection seems to happen at the late 30s stage.  And, as far as a team is concerned, why would they care about protecting the arm of CC, Santana et al for 10 years down the road?


#12    Tangotiger      (see all posts) 2007/07/19 (Thu) @ 12:03

Another update.  Look for:
UPDATE (Thursday):


#13    tangotiger      (see all posts) 2007/07/20 (Fri) @ 14:08

http://baseballprospectus.com/article.php?articleid=6477

I don’t understand half of what Tom is talking about here, but I think he’s saying that pitchers today are pretty good and lasting longer. And that Bob Feller should shut the hell up.

Note to Will:

My two-line summary is that
1. pitchers today have the same amount of career mileage (batters faced or pitches thrown) on their arms as pitchers from 10, 20, 30, 40 years ago

2. the difference is that the babying of pitchers today in their 20s allows them to pitch (and more effectively) into their late 30s, early 40s, much more than pitchers of yesteryear.

The one-line summary is that the mileage has simply been shifted so that you pitch fewer per year, but you get more years, so that overall, it’s the exact same mileage.


#14          (see all posts) 2007/07/20 (Fri) @ 14:43

TT,

You say “the same amount of career mileage (batters faced or pitches thrown)...as pitchers from 10, 20, 30, 40 years ago”.  I saw the “batters faced” part; where did you discuss pitches thrown?

My first reaction on reading the BF history was that improvements in medicine and handling pitchers in-game with their long term health in mind ("babying", if you must) are offsetting the steady increase in effort per batter over time.  That effort shows up both as increased pitches per batter faced (due to small strike zones, nibbling more, more selective hitters, etc.) and as more effort per pitch thrown.  Nibbling more is a direct consequence of the increasingly dire conseequences of throwing a ball down the middle of the plate—lineups are tougher top to bottom than ever, extra base hit rates are high, bunting is down, etc.

Effort per pitch is probably impossible to quantify, but there’s hope for pitches per batter.  Do we have pitch counts for enough history to track pitches per BF over a few decades, to see the trend?


#15    tangotiger      (see all posts) 2007/07/20 (Fri) @ 15:20

David,

Your “effort” point was pre-echoed by Chris in post #1.  This is a certainly plausible explanation that the gain in technology, medicine, conditioning and other advancements is pretty much exactly offset by the apparent extra effort it takes to throw a baseball today.  I can’t dismiss this.

As for pitch counts, batters faced and pitch counts are highly correlated when broken down by BB and K per PA.  In terms of BB/PA and K/PA, pitchers since 2002 that most match Koufax are: Clemens, Peavy, Jason Schmidt, Beckett, Burnett, Prior.

Since 2002:

Starter, BFP, pitches, per batter
Prior, 2771, 11148, 4.02
Schmidt, 4146, 16717, 4.03
Clemens, 3813, 15717, 4.12
Beckett, 3307, 14235, 4.30
Burnett, 2890, 12505, 4.33
Peavy, 3609, 16070, 4.45

Of the 232 starts I have of Koufax:
Koufax, 105 pitches per start, 27.6 batters per start, 3.81 pitches per start

Hmmm… seems that I have a little wrinkle with my theory.  It seems that if Koufax were to pitch today, he’d end up throwing at least 5% more pitches per batter, even if he were to end up with the exact same number of walks and strikeouts.  This flies in the face of my pitch-count Markov process (which I can explain in more detail for those interested).

That aside, 10,000 batters today would be like 10,500 batters 40 years ago in terms of pitches thrown.  So, nothing that would change our conclusion.

The original contention, about “stress per pitch” changing still holds though.


#16    Mike Green      (see all posts) 2007/07/20 (Fri) @ 15:20

Excellent, Tango.  It seems to me hard to justify the desire to have starting pitchers throw 7 innings every 5 games, bearing in mind the performance improvements in the relief role documented by Steve Treder, the lack of flexibility in adjusting which pitchers are used in situations to the leverage of the situation, and the lack of any overall mileage improvements which you document well here. 

If Johan Santana starts a game and goes 5 innings and the Twins lead 10-1, what precisely do the Twins gain by having him go 7 or 9 innings, and is the miniscule benefit worth the lost mileage? For that matter, is the situation any different if the Twins are ahead 10-1 after 3 innings?


#17    tangotiger      (see all posts) 2007/07/20 (Fri) @ 15:25

Btw, Jason Schmidt, probably our best comp to Koufax since 2002, has 27.5 batters faced and 111 pitches per start.  This is pretty much exactly what Koufax did. (The difference is Koufax pitched more games per year.)


#18    tangotiger      (see all posts) 2007/07/20 (Fri) @ 15:33

Continuing with the car analogy, you certainly wouldn’t want to stop/start your engine every time you get to a red light. 

Warm up throws also takes a certain amount of toll. 

And I imagine breaking pitches (the equivalent of driving 50mph to 80mph back to 50 mph) would take more toll than a fastball (driving at a constant 65mph). 

And a sudden acceleration (pitchers today have to pitch max effort almost all the time) will use up more mileage than a steady acceleation (pitchers of back then could pace every now and then, apparently).

With the improvement in oiling the engine (medicine, technology) these days, when all is said and done, it seems that the 1957 Chevy gets you the same thing as a 2007 Chevy.  Not really what one should expect.


#19    tangotiger      (see all posts) 2007/07/20 (Fri) @ 15:54

Another interesting thing about Koufax (and generally about pitchers of that era):

40% of Koufax starts had him with at least 120 pitches
but… 27% of his starts had at with less than 75 pitches

***

Of those in the log, he had 81 relief games, including 4 starter-like games: 110 pitches, 88, 76, 75.  His median number of pitches in relief was 23, with 3.97 relief pitches per batter faced.


#20    Chris Miller      (see all posts) 2007/07/20 (Fri) @ 16:03

It makes me wonder if the best bet would be for teams to use their ace’s up while their under club control.  Go back to 300+ innings and when free agency comes let some other team deal with the mileage.  Just a thought.


#21    tangotiger      (see all posts) 2007/07/20 (Fri) @ 16:57

I’d definitely do that. 

I’ve advocated on this blog a return to the way Earl Weaver handled his starters.  Put him in middle relief for at least half a season to a season and a half.  Then, when he’s 23-25 years old, he’s in the starting rotation.  You have him there for 4 1/2 to 5 1/2 season at 1000 batters per season.  Basically, you’ve got yourself a starter, in tip-top shape at ages 24, 25, 26, 27, 28.  Dump him after that, and take the two draft picks that comes with it.

http://www.insidethebook.com/ee/index.php/site/comments/liriano_meet_earl_weaver/


#22    Mike Green      (see all posts) 2007/07/20 (Fri) @ 17:38

It is a funny dynamic.  Teams have an incentive to use up a young ace.  The ace has an incentive to keep some in the tank for free agency years, but the culture of baseball ("pitcher wins”, “hurt not harm") leads pitchers to ignore the monetary cues. 

The other option for clubs is to reject the 5 man rotation entirely and to try to maximize leverage for the better pitchers on the club, with shorter, more frequent outings.


#23    tangotiger      (see all posts) 2007/07/20 (Fri) @ 18:02

I’m going to retract my calculations in post #15.  My fault for using two different sources.

Prior, 4.04
Clemens, 3.93
Schmidt, 3.92
Peavy, 3.92
Burnett, 3.82

So, it seems that it’s entirely reasonable to presume that Koufax’s 3.81 pitches per batter faced as a starter (and if you include his pitches and relief appearance of 3.97 would put him between AJ and Peavy) is NOT at all era-dependent.

The theory lives on.


#24    tangotiger      (see all posts) 2007/12/02 (Sun) @ 14:26

I’m bumping this, in relation to the Santana discussion in the other thread.  This is the relevant passage:

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?


#25    Anthony      (see all posts) 2007/12/02 (Sun) @ 16:28

I looked for pitchers, like Santana, with at least 200 IP and an ERA below 3.50 each year from age 25 to 28 during the expansion era. I only found ten (Clemens, Hooten, Hunter, Jenkins, Maddux, Marichal, Osteen, Palmer, Seaver, Stieb). At age 25-28, they averaged 273 IP, 1100 BFP and a 2.72 ERA. This is what they did after:

Age N IP BFP ERA
29 10 258 1040 2.73
30 10 255 1035 2.97
31 10 237 961 3.08
32 10 234 942 2.88
33 10 216 898 3.41
34 9 180 741 3.19
35 9 168 695 3.51
36 8 141 591 3.40
37 6 112 465 3.76
38 6 81 344 4.17
39 5 80 337 3.98
40 4 84 354 3.89
41 4 67 280 3.81
42 2 39 164 3.46
43 1 21 84 1.87
44 1 11 45 2.30

That’s obviously Clemens at the end. I divided the IP & BFP by 10, even after guys dropped out of the sample.

The sample size stinks, but I wanted to compare Santana to just the elite, not the very good.

If we use ERA+ >= 130 and 800 IP cumulative over those four years, we get 17 pitchers. Still not a great sample. (http://www.baseball-reference.com/pi/shareit/R3es)


#26    Tangotiger      (see all posts) 2007/12/03 (Mon) @ 11:39

Taking Anthony’s list, if someone wants to throw these names in their Lahman or BDB database, and see how they did in their ages 29-32:
martipe02
maddugr01
clemero02
santajo02
maricju01
rijojo01
seaveto01
koufasa01
appieke01
hudsoti01
webbbr01
oswalro01
koosmje01
palmeji01
stiebda01
mcdowsa01
mussimi01
jenkife01
glavito02
gibsobo01
drysddo01
blylebe01
hamptmi01
hentgpa01
suttodo01

hershor01
tiantlu01
keyji01s
rogerst01
mcdowja01
violafr01
lackejo01
colonba01
hunteca01
hootobu01
malonji01
finlech01
barrji01
kaatji01
buehrma01
bluevi01
mcnalda01
chancde01
sotoma01
drabedo01
smoltjo01
radkebr01
neaglde01
messean01
shortch02

Do one for the top 25, and another for the next 25 (or do it for all the top 50).


#27    Anthony      (see all posts) 2007/12/03 (Mon) @ 15:38

Taking those two groups and getting rid of the active players under 32 (Oswalt, Lackey, Webb, Santana, Buehrle) this is what I get:

Top 25

Age N IP BFP ERA+
25-28 22 241 986 138
29 22 234 960 134
30 22 218 898 123
31 21 212 867 132
32 20 201 824 132

Next 25

Age N IP BFP ERA+
25-28 22 226 930 121
29 22 241 992 119
30 22 201 833 113
31 21 174 725 112
32 20 136 564 111


#28    tangotiger      (see all posts) 2007/12/03 (Mon) @ 17:08

Anthony: Great job! When I see “564” in the BFP for the age 32 in the second group, is that the average for the 20 players remaining, or for all 22?

***

Note a 10 point drop in ERA+ means a 30-35 point drop in actual ERA.

If you are at 140 ERA+, this implies an ERA of 2.86 (in a league of 4.00).  A 0.09 ERA gain year over year means ERAs of: 2.95, 3.04, 3.13, 3.22, which averages 3.08, which makes it an ERA+ of 130 ERA+ over those 4 years.

***

The age 29-32 compares very favorably to the age 25-28.  If you merge the two groups, the age 29 actually averaged more than the 25-28 average, and from that point onwards, you get a 10% decline in BFP.

The decline increases as the performance of the pitchers worsens.  That is, the better you have performed, the more likely you are not close to a replacement level, and the longer you can pitch. 

If you get horses who have an ERA+ of 100 or worse, you can pretty much bet that their BFP will drop at a much faster rate than 10%, simply because attrition will catch up to them much faster.

A rough rule can be (for age 25-28 pitchers):
5% drop for 140 ERA+
15% drop for 120 ERA+
25% drop for 100 ERA+
35% drop for 80 ERA+ (i.e., already around replacement, and set to go to the bullpen in 2 years).


#29    Anthony      (see all posts) 2007/12/03 (Mon) @ 18:24

Just checked: the total BFP for the age 32 line is 12,413. So the 564 comes from dividing by 22.


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