By Roger Weber

 

When teams make trades the media usually focuses on the player's history. They like to give lists of statistics, tables of previous years' numbers. There is a lot more time spent on how a player has performed in the past than on how he may perform in the future. And when discussing how a player will fare, usually it is assumed he will play about the same as he played the last few years, usually adding a few points to averages and a few more home runs. There is no real science to it.

 

This idea that statistics will remain constant is usually flawed. There is great variation from year to year in statistics. But making that variation seem even larger is the failure of many analyses to recognize the general trends of aging. As players increase in age they tend to get better at a decreasing rate until they level off briefly before their stats begin to wane as they near the end of their careers.

 

The assumption often is that the up and down is minimal and that careers peak sometime after age 30. A career can often be measured by a parabola, with early and end-of-career performance much lower than peak production. It is this way that many teams end up paying far too much for over-the-hill players. The assumption that a 32 or 33-year old player is still in his peak years also often contributes to this phenomenon.

 

Players with "power bats" often peak as early as 25 or 27, but the peak generally is very different from player to player but often comes when the player is much younger than many fans suspect. That is one reason that so many players develop such lofty expectations. Fans think the player is still youthful at 25 or 26 and assume he should still improve into his 30s, but often he does not and the player is criticized for falling short of expectations or never living up to potential when in reality it was the expectation that was flawed.

 

Below is a chart of age peaks of famous offensive players based on a parabolic (wave-like curving) computer generated model:

 

Player	Age at peak
Babe Ruth	30
Willie Mays	31
Mickey Mantle	26
Hank Aaron	29
Johnny Bench	26
Frank Robinson	25/26
Mike Schmidt	30
Hank Greenberg	29

 

As you can see, the peak points of careers vary but are rarely as late as the 31 or 32 that is often believed. And it is worth noting that these peaks are based on the major statistics like home runs, whose totals often remain high a little after a player's true peak. Young talent is and should be more coveted in baseball. It comes cheaper and is often better and more polished than some fans might presume.