EconoBall: Rethinking "Prime"

EconoBall: Rethinking "Prime"

We talk a lot about a player's "prime years" here at CubsDen.  The general idea is that a player gradually increases production through his early twenties, reaches a peak somewhere between the ages of 27 and 32, and then declines afterwards.

This trend can be seen clearly in the numbers of one of the best pure hitters of his generation, David Ortiz (click on the picture to see the full size version):



If you look at Ortiz's home run totals, the fall off after his MVP-caliber 2005 and 2006 seasons is extremely stark, dropping almost in half from his 2006 peak to his 2008 and 2009 seasons.  The data suggests a similar pattern for all batters.  The chart below gives the number of home runs, on average, a batter hits relative to his age 28 season.

21 -5.98679 26 -0.09699 31 -0.76019 36 -4.58266
22 -3.88288 27 0.352327 32 -1.52031 37 -5.71614
23 -2.54475 28 33 -2.06003 38 -6.97009
24 -1.99815 29 0.093975 34 -2.77352 39 -7.4139
25 -0.59327 30 -0.26512 35 -3.421 40 -8.65053

So, on average, a batter hits 2 home runs a year less in his age 33 season than in his age 28 season.  He is also likely to hit roughly 2 home runs a year less in his age 24 season as his age 28 season.

Math stuff starts here

The numbers above, and all numbers in this article, are the result of linear regression analysis run on all batters with more than 100 PAs from 1947 to 2013.  All regressions include player level controls.

Ideally, I'd like to control for seasons, as well.  However, there is a mathematical problem with this.  Player age and season are strongly correlated.  That is, a player's who is 25 in 1985 will necessarily be 30 in 1990.  Add to this a general increase in home runs over time.  Because of this, the regression cannot distinguish between increases in home runs over time and the increase in home runs a player experiences on his way to his prime.  In the regression run with controls for seasons, the result suggests that players hit fewer home runs every season they play (i.e., fewer home runs at 19 than 18 and far fewer home at 26 than 20) and experience large increases in home runs per season -- on the order of 100 HR per player between 1947 and 2013.  The results are statistically insignificant and and run contrary to logic so they were discarded.

Fortunately, given a similar distribution of players by age over time, the results should still be unbiased without controls for season.

Math stuff stops here

However, if you look at Ortiz's OPS numbers you'll see the fall-off isn't nearly as extreme.  What's happening here?  One thing is that doubles are increasing, suggesting that aging players have hits that used to leave the park for home runs go for doubles, instead.  I'll address this possibility in a future article.  However, you'll also notice that his plate appearances are decreasing over time.

It turns out, this is specific to Ortiz alone.  Instead of considering raw home runs, I considered home runs per plate appearance, or home run percentage.

21 -0.710% 26 -0.045% 31 -0.023% 36 -0.302%
22 -0.400% 27 0.029% 32 -0.087% 37 -0.349%
23 -0.279% 28 33 -0.118% 38 -0.513%
24 -0.260% 29 0.051% 34 -0.109% 39 -0.340%
25 -0.078% 30 -0.004% 35 -0.168% 40 -0.484%

These numbers show a similar pattern to the raw home run numbers, a strong increase to ages 27-29 and slow decrease after.  However, notice that the falloff is nearly as strong as the raw numbers.  The average batter has almost a greater than 1% higher home run percentage at age 33 than 24 and the home run percentage doesn't drop below the rate of a 24 year old until the batter hits 36 years old.   It is worth noting that these are the trends seen in ALL batters.  David Ortiz has a much greater increase into his prime and, similarly, a larger falloff after.  The next phase to this line of analysis would be to break hitters up into different groupings (e.g., power hitter, leadoff man, utility infielder) and determine if production evolves over time differently for different types of players.

The analysis suggests that the strong production that comes during a player's prime is the result of two factors: increased production from being in a player's physical prime as well as more AB's as a player in his mid 30s experiences aches and pains that require missed games or trips to the disabled list.  An important take away from this is that players leaving their prime have benefits above the raw numbers because, in effect, their performance is condensed into fewer at bats.  This allows a deep team to get production out of utility players while their aging, elite players are on the bench.

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  • Does this info take into account his possible PED usage?

    And I'm being serious.

  • In reply to J Quinn:

    The thought popped into my head too. Not sure how we could ever account for it though.

  • In reply to HoosierDaddy:

    Mike and I were discussing his piece and it popped into my head as well. I do not believe PEDs make you a better baseball player, but I do believe they speed up recovery time, a time frame that tends to increase once a player gets past his prime years. It's more about that player having less of the downs and the muscle fatigue as the season goes on and being able to sustain high levels of performance for longer periods of time. In other words, it doesn't make you a better player, it allows you to play more often at your personal peak level of performance. That is why it doesn't make bad players good, because their peaks aren't that good to begin with, but it certainly seems to help players who already have significant talent.

  • In reply to John Arguello:

    Based on the home totals during the PED era, I do think it created more power, even in some weaker hitters of the time. There was a player, I think with Baltimore, who had a 2 year window of over 40 home runs compared to much lower totals the rest of his career. I believe there are many similar examples. I guess you could say that doesn't necessarily mean he is a better player, but many would argue that he is.

  • In reply to Cphil:

    I think you might be talking about Anderson, but he was a pretty talented guy, considered a very good prospect. I just look at him as a fluke, however, much as you see all around baseball except that his career season was magnified even more.

  • In reply to John Arguello:

    At the time I think many fans thought S Sosa was one of the best players ever. I think the use of PEDs made him (and many others) "better players". If you want to say they were better players primarily because of recovery time, that is possible.

  • In reply to Cphil:

    There have always been players who have fluke HR seasons. Roger Maris for instance. I don't think anyone accuses him of cheating.

  • In reply to mjvz:

    I.E. Davey Johnson in 13 years he hit 130 homers, he hit 43 homers in 1973 alone. I think his next closest year was 15 homers.

  • In reply to bleachercreature:

    in fact Johnson hit 93 of his 130 homers from age 27-31.
    in full seasons from age 23-26 he averaged 8 homers. that's why guys like Castro and Castillo are going to have their power breakout years in the next few years (if they have them at all).

  • In reply to mjvz:

    Maris hit 39 HRs in 1960, doing this in 136 games. There's no evidence that Maris or anyone of that generation cheated. There's proof that guys in Anderson's generation cheated. Could Anderson's 50 HR season have just been a fluke and not PED related? Sure. However, based on what was going on throughout baseball at the time, he doesn't earn the benefit of the doubt.

  • In reply to Cphil:

    But actual strength is not synonymous with HR power. like john said, the only real advantage PED's would give is quicker recovery time, less fatigue, and extended levels of peak performance.

  • In reply to HoosierDaddy:

    That's quicker recovery time from workouts, too, increasing strength. There's no question steroids helped make some warning track hitters into HR guys.

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    In reply to John Arguello:

    It was actually that conversation that made me realize the importance of individual-level controls. It did have an impact as the original results had HR/PA increasing through a player's age 39 season. That seems to have been the result of two effects: 1st may well have been steroids which allowed players to prolong their careers and 2nd is that elite players tend to play longer anyway. So, for example, David Ortiz is still playing at age 38 whereas Blake DeWitt appears to be involuntarily retired at age 27.

  • In reply to John Arguello:

    I wholeheartedly disagree.. there is a reason why homeruns are way down.. people hitting 50 to 70 hrs made them better. Since no one is doing that now that mlb is cracking down on it should be proof enough imo

  • In reply to John Arguello:

    I dont know John. Guys like Ken Caminiti and Brady Anderson had years where there production certainly was well beyond career norms, a recent example might be AJ Pierzynski hitting 35 hrs with the White Sux several yrs ago, double his career norm.

  • In reply to John Arguello:

    "I do not believe PEDs make you a better baseball player,..."

    Are you serious? You think Sammy hits 60+ HR's if he's not using PEDs? The HR have dropped off a cliff since baseball started testing for PEDs. Sure, the PEDs speed up the recovery time but they also make you a better baseball player. Bonds had HOF numbers before the PEDs (he stayed healthy), but he put up video game numbers with PEDs.

  • In reply to Bill Oliger:

    From a skills standpoint it does not make a player better. Does it help them achieve better results? Possibly, but those are two different things.

  • In reply to John Arguello:

    Look at Ryan Braun and his numbers after he was finally nailed to the wall. Way below his season averages.

  • In reply to Chupacabra:

    Did his actual baseball skill suddenly decrease or are their other factors that affect performance? Don't be so quick to equate the two. They are not the same things. This site has covered that same question in different formats. You can jump to a lot of quick (and false) conclusions by looking at results and assume it tells you everything about process.

  • In reply to John Arguello:

    Fair enough.

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    In reply to J Quinn:

    The player level controls should account for some of that. The danger would be if a player has systematically higher numbers through his prime years than other years as a result of PEDs. Part of the idea of using so many players over so long a time period was to minimize the impact of the steroids era.

  • In reply to Mike Moody:

    Thanks for the responses guys.

  • In reply to Mike Moody:

    It might be interesting to rerun the numbers minus the time period of say, 1995 through 2005 and see if their is any dramatic difference in the results.

  • In reply to Northside Neuman:

    Or with a dummy variable for whether they were named in the Mitchell report although I like the above idea.

  • Cool stuff as usual Mike. I've always intuitively thought that there was a 'peak' in that 26-30 window for most position players as far as output - be also kind of wondered how much of the drop-off post ~30-32 age was due directly to less time on the field, rather than absolute regression in skills.

    Kind of the injury and recovery factor - with the given that older players tend to pile up more lingering injury problems and take longer to recover from them - but partially balanced by some increase in overall 'expertise' that the additional playing time has given them.

  • Interesting read Mike. It made me pull up Sosa's stats out of curiosity. Ironically, his 24yo season of 33 HR's and his 35yo season with 35 HR's, falls right in line with your findings. It's a shame an AL team didn't grab him for another year or two to contribute as a platoon/DH guy. maybe it was his rep/attitude that wouldn't allow that. IDK.

    This is also a reminder for us all to temper our expectations of immediate success for guys like Baez, Bryant, Soler, etc... Mike Trout sort of skews my point, but IDK that we should be counting on our top prospects to come up and immediately hit 30+ HR's... They're all still really young.

  • Mike, this analysis not only shows value to aging, elite players but is a good argument for maintaining value in these types of players with the use of the DH. I have never been a fan but as the data suggests it provides American League teams with a big advantage in maintaining value of elite hitters. This not only applies to your own players but significantly to free agent acquisitions.

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    In reply to Cphil:

    It does make a case for the DH, I admit. I'm with you in not being a fan but, with Interleague play here to stay, I think it's time to admit defeat and allow it into the NL.

  • In reply to Mike Moody:

    Both leagues need to be the same and I know that means GH will probably prevail.

  • In reply to Mike Moody:

    Or remove it from the AL. I know that won't happen because people like home runs but the lack of strategy in the AL ruins it for me.

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    In reply to hawkmcd:

    It won't happen because the idea is a non-starter for the Players' Union.

  • In reply to hawkmcd:

    I don't see how the "strategy" of having to decide between pinch hitting for a crappy hitting pitcher in a potential run scoring game situation versus keeping him on the mound if he is pitching well, adds anything to the games enjoyment. The fact is that AL teams put much more strategy pre-game into the lineup card, as they can put a positional starter in the DH role to keep the best hitters in the lineup, while adding another player to attack the pitcher for the day. They can put the DH anywhere in the lineup, etc, etc. The NL teams have a lot less options with regards to lineup strategy, and their only option in resting a top player is to remove him from the lineup all together. Also as I said earlier, I don't see the value in a manager removing a pitcher who is doing well as far as game enjoyment goes. If the opposing team wants to remove the pitcher then run the pitch counts up or hit the ball. This is without even considering the Free Agent implications and the big disadvantage that NL clubs have when considering signing top players who require long term deals. An AL club knows they can move the player to DH in his later years, or even consider a shorter term contract for say a top catcher, the NL team must judge his value on the 120 or so games that he could be in the lineup (even pinch hitting is rare because of the injury possibility in game with catchers and needing a backup), at the same time the AL team knows that they can play him at DH for the other games, which again goes back to the pre-game strategy. Lets say Schwarber ends up staying at Catcher and turns into the middle of the order bat that we expect....Is it really more enjoyable to have one of a teams best hitters on the bench for 30-40 games? Or would we put him in LF for those games and remove Bryant or Soler who might be great players in their own right? In my opinion, the DH allows a team to play more of it's best hitters, adjust their lineup to face a particular pitcher/team with better options, and removes run scoring from the equation when deciding the fate of the games pitcher...which all strengthen the quality of competition in the game.

  • In reply to Ghost Dawg:

    Yes. It's more enjoyable - to me - to see how a manager MANAGES around a crappy-hitting pitcher to create offense but still keep a good arm on the mound. It's more enjoyable - to me - to see players who play their positions instead of simply hanging around for their next turn at bat. It's more enjoyable - to me - to see the next generation of ballplayers "arrive" instead of being blocked by someone who can't play the field anymore but is kept around for his bat. And, I'll ask again - if designated hitters, why not designated runners, fielders, throwers, and anything else a particular player isn't good at anymore? No, thanks. I like my baseball undesignated, please...

  • In reply to Cliff1969:

    RE: "to see the next generation of ballplayers "arrive" instead of being blocked by someone who can't play the field anymore"

    That doesn't make any sense. The DH adds 30 spots to the AL as roster opportunities, and would do the same for the NL. That's 60 spots that would not exist to give players the opportunity to play. Also, with no DH older vets that can still hit are played at 1st or LF, etc, when they could be playing DH and open up a spot for a younger player, So your reasoning is wrong.

    RE: "if designated hitters, why not designated runners, fielders, throwers"

    Because that is a false argument which has nothing to do with anything. Nobody is suggesting any of those other "designations", and to suggest that adding the DH to the NL when the DH has been in existence for 40 years in the AL and every other professional baseball league in the world (besides the NL, & NPB Central League) with no talk of adding those other "designations" is an example of Slippery Slope Fallacy, i.e if you allow a camel to poke his nose into the tent, soon the whole camel will follow.

  • In reply to Ghost Dawg:

    Edit: 60 more playing/starting opportunities/spots not roster opportunities

  • In reply to Ghost Dawg:

    Please. How does the DH "add" any spots to the major league roster. Aren't they still set at 25? If you make someone a DH that can't field any more, someone else who CAN field loses a spot. There isn't anything "wrong" with that reasoning, I learned to cipher in the 6th grade, just before we studied the "gazintas."
    As for my, um, "false" argument, I never said the DH is a slippery slope that will lead to designated other tasks. In my opinion, every argument you make for the DH is applicable to any other designated "whatever." Extends careers. Let's a poor "x" continue to play. Eliminates having to watch a player who is poor at "x". If that logic works for hitting, it works for running, fielding, etc.
    It's not that the arguments in favor of the DH are "bad," it's simply a matter of preference. If (some say when) the NL adopts the DH, I'll cuss and grumble and look for Vogelbomb to get to the majors, like everyone else. I just prefer my baseball without the DH.

  • In reply to Cliff1969:

    Yeah, that's why I edited it to "playing/starting opportunities" instead of roster opportunities...which you chose to ignore.

    RE: "If you make someone a DH that can't field any more, someone else who CAN field loses a spot. There isn't anything "wrong" with that reasoning"

    Huh? Yes their is. How does moving a guy who can't field anymore to the DH lose a spot for another player? It doesn't. It OPENS a spot, (the position he just left from) again, you have the right to your own can hate the DH...but that logic makes NO sense.

  • In reply to Cliff1969:

    @cliff1969 I apologize for saying that your logic doesn't make sense, I was talking in terms of starting/playing opportunities, while it appears you meant it in terms of a roster spot. Your logic is sound, I'm just having a tough day, and I snapped to answer too quickly. We disagree but that's fine. Have a nice night.

  • In reply to Cliff1969:

    You're one of the most knowledgeable posters on the site, Ghost, and one of the reasons I enjoy reading the posts almost as much as the articles themselves. Your passion for the game is boundless (as is mine.) I don't expect we'll agree on everything, but we're probably in agreement a lot more than we aren't! Hope your night was peaceful.

  • I don't want to sparse words however, if you are on PEDS's which allows you to prolong your "peak" performance periods...You are a better baseball player. The results of this are clearly evident in the stats.

  • In reply to MilwaukeeRoad:

    It does not increase your skill level as a ballplayer in any way.

  • In reply to John Arguello:

    The synthetic steroids bonds took was proven to improve eyesight.. so again I disagree. Improved strength and hand eye coordination improves skill

  • In reply to CubfanInUT:

    Eyesight and hand-eye coordination are two different things.

  • In reply to John Arguello:

    Some of the stuff in the sports gene seem to make a pretty compelling case that the eyesight matters more. I actually heard the author interviewed and haven't read it yet so take this with a grain of salt but I think it would be an interesting read.

  • In reply to John Arguello:

    Ted Williams always credited his eyesight as a reason why he was such a great hitter. He never went to a movie just to protect his eyes.

  • In reply to CubfanInUT:

    Bonds late in his career was hitting most of his HRs to center and Left-center, contrary to the early years where his power was mostly pull power. Roid use certainly seemed to help Bonds career.

  • In reply to John Arguello:

    IMO it increases bat speed which gives a hitter that split second longer to recognize a pitch and clobber it.

    The reason pitchers dominate now is they had to develop weapons to get the monsters out. Downside is pitchers blowing out their arms.

  • In reply to John Arguello:

    It may not increase skill level, but I think we can all agree PEDs increases production. Players spending less time on the DL is one example of this…

  • In reply to cubbiefan60:

    Bonds had 3 knee operations on 2005. Many SF fans put the blame on roids.

  • In reply to John Arguello:

    Except if it increased your bat speed and running ability. I've read stories of ball players taking PEDs in order to increase their HR counts, never because of their ability to bounce back after a game.

  • In reply to John Arguello:

    PED's do not increase your skill, correct. However PED's such as steroids or human growth hormone are proven to increase muscle mass greatly under the same strength training regimen. It also allows your body to heal quicker, and when you workout the muscle will reach a point where it can no longer lift the amount of weight being pressed. This is called lifting to failure. When the muscle is pushed to this point, tiny tears in the muscle occur. These tiny tears will rebuild over a 48 hour period of rest and gain muscle mass in the process. This is the same muscle that will burn more fat on the body and thus burn more calories. That cycle is responsible for the quick muscle added muscle mass and strength that PED's can provide a player (or anybody) with. Obviously if a player couldn't hit a CB before he will not be able to hit one now, but if he already has the skills, it most certainly can give you the added strength to hit the ball farther, i.e. you are hitting the same balls (assuming it doesn't add to your bat speed, although it might) but instead of the ball going to the warning track, it's hitting the wall or going over it. In the same way that some prospects will go from doubles power to HR power as their body matures and they add muscle mass is the same way that an older player can do the same thing through the help of PED's.

  • I think using a guy who has strong inclinations to steroids/hgh isn't the best subject to use as an advantage

  • In reply to CubfanInUT:

    I think it's more the era that he played / plays in than suspicion about his use of PEDs. It's difficult to get pure numbers from data created during the steroid era.

  • *example

  • Remind me again why the Twins ever got rid of Ortiz?

  • In reply to BobMiller146:

    No good reason.

  • In reply to BobMiller146:

    I live in northwest Iowa and there are a lot of Twins fans up here. Whenever they talk about Ortiz or Boston the number one statement is "why couldn't he do that with the Twins?" I always laugh because the power numbers were always there, and they non-tendered him after he hit 20 hr's as a 26 yr old.

  • In reply to BobMiller146:

    The same reason why they overpaid Joe Mauer. They are poor judges of talent, and when they have it, they don't know what to do with it.

  • In reply to Tinker Evers Chance:

    Is that actually the case? I know they had some bad years with some FO changes but aside from the last few years they've had some pretty consistent results. I don't know about talent development but with that market I'd assume they did a good job. And they currently have a good farm system. Couple bad injury breaks with M&M. Not saying it's what I think happened but it's possible they knew what Ortiz was on and didn't want any part of it. I seem to remember reading emails of theo with the sox indicating a player or two they were looking at and taking that (suspension risk, etc) into account

  • In reply to hawkmcd:

    The Twinkies are "consistently" running out MLB's worst starting pitching for the past few years, signing as many "has been" and 'never will be" pitchers as humanly possible. If you think Edwin Jackson was a poor signing for the Cubs, then check out Correia, Pelfrey, Worley, and Nolasco. Then look at all the pitchers that have left the team via trade, free agency, etc. - e.g., Lohse, Garza, Liriano, Santana, Nathan. Yikes!!!.

    They sign other FAs who turn out a career year and then tank (Willingham, Suzuki(?) the next year before the team's management thinks about trading them. When I see a FA with a career year, my first reaction is what can we get for him before he slides, not pat myself on the back and then watch him slide. The Twins seem to think that one or two free agent signings are going to make them a contender again. They don't seem to catch on to the concept of flipping.

    They gave Mauer $23M per year for 8 years (2011-2018) based upon 1 power year (2009). Before that year, he never had that kind of power, and he has never had that kind of power since. He is on the DL almost as much as he is off it. Once he "strained his neck" trying to catch a pop fly and had to sit out for a week. He was lambasted in the local press just a couple of weeks ago for poor off-season preparation. That happened a couple of years ago as well when he had problems with "lateral leg movement".. They gave the local boy a sweetheart deal when they should have let him walk to the Yankees who were beckoning. Now they have a singles/doubles hitter occasionally playing 1B for them when he isn't making commercials and when most teams look for power from that position.

    They brought CF Aaron Hicks up from AA when he was not at all ready for it. The kid's confidence went in the tank and he still hasn't recovered from the experience. This after they traded away their two previous CFs (Span and Revere). Anybody recall what they got for them? It's not memorable, but I think the Nats still like Span.

    I know the Tins get high marks for their farm system, but it really hasn't resulted in much yet. Sano needed shoulder surgery last fall, but the Twins wanted to see if it would heal on its own. He finally went under the knife at the beginning of spring training. Buxton has been hobbled much of the year. What else is there? Gibson is suspect. Alex Meyers? I think their system is over-rated.

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    In reply to Tinker Evers Chance:

    OK, but be honest now: Tell us what you REALLY think about the Twins.

  • In reply to Tim McCann:

    LOL!!! What I really think?

    The Twinkle Sticks are a perfect example of how not to run a team, from the top (the owners) on down through the GM and down to the manager and the pitching coach. I'd clean the entire house.

    And their fans are strictly fair weather. Attendance at Target Field, which is a beautiful stadium (but it needs a retractable roof), has been sliding ever since they built it, because what is on the field is a AAA team.

    Cubs fans on the other hand, are, as Eddie Vedder says, foul weather fans.

  • In reply to Tinker Evers Chance:

    But, they have "Homer Hankies!"

  • In reply to Cliff1969:


    They need to give one to Brian Duensing for his famous crying jag in the dugout the last time they were in the playoffs against the Yankees.

  • In reply to Tinker Evers Chance:

    Sano had TJS not shoulder surgery.

  • In reply to John57:

    Same difference. They knew he needed it at the end of the 2013 season and needlessly delayed it. They set back his development because they took the short term view and hoped he could play through it.

  • Good work! This is one of many reasons why I enjoy reading Cubs Den so much. Thank you!

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    When John and Mike discussed the thought of PED's for Papi, you should of changed your subject right then. Maybe, the Big Skirt would of been a better subject (although he was called in front of Congress, got hurt all the time while sitting on the bench as DH, was surly all the time, fought with team mates, went to SEC football....)

    Papi was called out in the same story that called out Sosa. Maybe Sosa used and Papi didn't. Maybe Papi used and Sosa didn't. Maybe they both used and maybe neither used. The point is WE DON'T KNOW.

    Maybe you should of looked at Barney!!!!

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    In reply to Randy Michelson:

    Honestly, I was looking for a hitter with plus power and hit tools who was nearing the end of his career. Papi was the first one who came to mind. If we accept the fact that he did use PEDS, then the numbers suggest that PEDs don't affect the trajectory of "prime" all that much, though they may impact the levels. He's really just an example to make the concepts more focused. He doesn't impact the analysis any more than any one player.

  • In reply to Mike Moody:

    Bonds would have been a good one, Mike.

  • In reply to Mike Moody:

    Is our thinking coming at the PED issue from the wrong direction? Maybe Ortiz is improving because the use of PEDs by PITCHERS is less prevalent?

  • In reply to Randy Michelson:

    I probably said that wrong, we just briefly broached the idea in general, not geared toward any specific player. He told me about what he was writing and the thought just popped in my head, but this excellent piece is all him.

  • In reply to Randy Michelson:

    I would have been happy to contribute to Barney's PED fund...

  • Another nice article Mike. I have really been enjoying reading your articles. I am curious if you might do a similar study with starting pitchers. I am interested in that subject because I really don't know what the numbers would show plus the Cubs are in the market for an age 30 TOR starter like Jon Lester.


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    In reply to couch:

    It's absolutely coming. Just deciding how to approach it. I'm thinking I might look at evolution of the hit tool over time next week because I have the data ready and this coming week is going to be kinda crazy with travel to the UA Game on my agenda.

  • In reply to Mike Moody:

    And I assume you'll separate out starters and relievers. Curious how you'll handle those who were both in different parts of their careers.

  • FWIW, Fangraphs did a piece on aging curves, as it relates to wOBA and wRC+, which is worth a read:

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    In reply to Eldrad:

    I'll have to look at it with my data. Without getting too technical, I think there may be some flaws in the methodology, which the author acknowledges in this quote:

    "A problem exist when using wOBA in the recent lower scoring environment. The league wOBA in 2006 was .337, and in 2013 it was at .318. That’s a drop of 19 points in seven seasons, or 2.7 points per season. Players will have the appearance of aging from season to season."

  • Hey Mike,
    I've always wondered about prime numbers related to defense and when the curve hits. I've just guessed that players prime a little earlier related to defense. Thoughts? I know that would be daunting, especially since defensive measuring is so challenging. The 27-32 prime years are based on a guys total WAR, not just offensive production usually, right?

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    I think generally that the prime pattern holds pretty well. Even looking at someone like Jeter the numbers slowly seem to decline over time. Of course with any numbers there are outliers, players that kept constant numbers throughout their careers. Or ones that peaked later. I have always thought about the peak/PED debate. Guys like Barry Bonds and Rodger Clemens who seemed to extend peak years for a decade. Clemens declined so much in 96 the Sox let him go. Was his comeback for the Jays always gonna be impressive or was it made by PED's? I'm not exactly sure.

  • Casey Crosby anyone?

  • In reply to apalifer:

    Cant stay on the mound, can't throw strikes...not sure about this stuff since his injury. Roster space getting tough to manage.

  • Dude can't play in more than 15-20 games a year for the last 5 years...

  • In reply to HoosierDaddy:

    ^^ In response to apalifer question on "Casey Crosby" ^^

  • In reply to HoosierDaddy:

    Still a kid though with a great arm...reclamation project?

  • In reply to apalifer:

    There's no denying Crosby's pure talent, big solid frame, LHP, 4 pitch mix... 2 of them plus offerings. The rare kind of LHP that can hit the upper 90's.

    None of that matters if he can't stay healthy. And he hasn't been able to for the last 5 years. It's going to come down to the medicals. He's had multiple elbow & shoulder issues. But what does it say if Detroit gave up on him...

  • When does warning track power become homerun power, after putting on x amount of pounds of muscle within a short offseason and long MLB season. The only way to do that is the workouts are longer with heavier weights with shorter recovery time. Oh yeah and PED's. The stat that would be interesting is where certain players outs occur, normal length fly outs vs. warning track outs, vs. home run distance. Then compare suspected PED use years vs. down years.

  • There's no doubt that Ortiz is one of the greatest hitters. It's hard to say how his career would have progressed without steroids in baseball (whether he ever used them, or he faced pitchers who did) and if he routinely fielded a position throughout his career. Interesting analysis, Mike & John.

  • Have to strongly disagree with the notion that steroids don't make players better. Based on production, which in the end determines quality, there really is no dispute that steroids increase performance. Up until the age of 35 (pre-steroid), Barry Bonds career high in hrs was 46, obp was .461, and slugging .677......after 35 (when most players careers are winding down and performance decreasing), his obp was well over .500 four consecutive years and he slugged over .749 four consecutive years. Steroids make hitters stronger and increases bat speed, which makes the ball go farther and harder. The numbers don't lie. Luis Gonzalez was borderline fourth outfielder until he started juicing. Todd Helton never hit more than 20 hrs after having averaged 35 during steroid era. Countless others as examples. I agree that steroids don't improve hand/eye coordination and reflexes, but it definitely increases bat speed and player strength. But production=quality and it is a fact that steroids increased production.

  • Reading the comment above that PEDs do not make you a better player (other than faster recovery time) are ludicrous. They make you bigger, stronger, and faster. All three strongly improve your performance in baseball and for that matter almost any other sport too.

  • In reply to Behn Wilson:

    Being a better ballplayer and achieving better performance aren't necessarily the same thing. It can make you a bigger, stronger version of the same ballplayer, but if you couldn't hit a curveball or throw one -- or if you had no discipline at the plate or no control on the mound, that is not going to change. If you lacked the hand-eye coordination to consistently barrel up or the athleticism to repeat your delivery, that isn't going to suddenly appear if you have bigger muscles. It can improve your performance in an indirect way, but not you skill level, unless being strong and being able to recover quickly is a skill. You are confusing two different things here.

  • In reply to John Arguello:

    Is a guy who hit .325 with 57 hrs not a better hitter than a guy who hit .258 with 10 hrs? That was Luis Gonzalez. He was 29 when he hit .258 with 10 hrs, which was basically his career norm. How did steroids not make him dramatically better??

  • In reply to sabzali:

    You really like this site, don't you Jonathan? I'm flattered at your efforts to keep coming back.

  • In reply to John Arguello:

    Its a given you have to have the skill set to be able to play in the majors. For those that do have the requisite skill, the steroids are going to improve them across the board. Being stronger helps your bat speed, power, pitching velocity, etc. Helps pitchers control as they don't have to exert as much effort to hit top velocity and can have better accuracy. Even non PED users perform better as they fill out and build up muscle over the years like Sandberg did adding a few pounds of muscle a year. These guys nowadays add what took him a decade to buildup on a six week steroid cycle. Even quicker with Growth Hormone.

  • In reply to Behn Wilson:

    Skill levels vary.

    Sorry, Behn but you're bending over backwards to make this fit. Steroids make you throw with less effort and help you throw strikes? C'mon now. That is quite a stretch.

    Sandberg got stronger, but last I checked, strength is not a skill. Similarly, you should ask yourself? Is better eyesight a skill? Is the ability for muscles to recover quickly a skill? Can more strength, better eyesight, and quicker recovery time help performance? Yes, but again, you are talking about two different things.

  • In reply to John Arguello:

    I am not going to argue on this anymore we will agree to disagree on this.

  • In reply to Behn Wilson:

    Agreed on the agree to disagree :)

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