Dispelling the idea that all hitters reach their prime at the same age.
My grandfather used to say that in heaven, everyone was 25. He figured that was the perfect age in life. You're old enough that you're not a kid any more, but young enough to enjoy everything. Grandpa lived to age 93, and more than six years later, I still miss the guy. This one's for you, Grandpa.
The old assumption that players peak around the age of 27 has long been the accepted standard, but should it be?
Recently, there's been a decent amount of chatter regarding how baseball players age, and I have to admit that it's mostly my fault. In a study that was recently published in Journal of Sports Sciences, I find that players tend to peak around the age of 29; this finding has been met with resistance from some individuals in the sabermetric community, where 27 has long been considered the age when players peak. Will Carroll and Christina Kahrl graciously asked if I would be willing to defend my findings on Baseball Prospectus. I agreed, and I thank Will and Christina for the opportunity to do so.
Due to the length of the explanation, I have broken the analysis into two parts. Part I explains the empirical problems faced when estimating aging, and examines why past sabermetric studies have failed to properly measure player aging; Part II explains my recent study.
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The players ranked from number 26 through 50 in the third annual ranking of the game's best.
Welcome, ladies and gents, to the third annual Baseball Prospectus Ultimate Fantasy Draft. What, you are probably wondering, is the Baseball Prospectus Ultimate Fantasy Draft? It is the answer to this question: If you were starting a baseball team from scratch, which players would you want to build your team around? That is, which players would you take-and in what order would you take them-if your goal was to win as many championships as possible over the medium-to-long-term?
After a quick bit of aging, the Astros' shortstop might not lose much to Father Time now, but the clock's ticking.
My first thought after I learned that Miguel Tejada was two years older than his listed birth date was that I wasn't really all that surprised by the news. My second thought was that he just threw away his shot at the Hall of Fame. One of these two thoughts is valid; the other is a little out of place. Let's take care of the obvious part first. Below is a comparison of Miguel Tejada's original PECOTA forecast with a new one that we've generated by aging him exactly two years and leaving everything else alone:
How has player age changed over time, and why is 2007 the year of the old player?
No doubt about it, hitters are getting older. A little over two months into 2007, the average age per plate appearance sits just below the all-time high achieved in 1945, when most young men were off fighting World War II. Why is age going up among hitters, and what are the implications for baseball?
Who might follow in the Rule-5 footsteps of Johan Santana? Dayn Perry has the lowdown on the top eligible players.
Baseball's annual Rule 5 draft is upon us (if you don't know what the Rule 5 draft is, here's Alan Schwarz's nifty explanation of it). It'll go down during the upcoming annual winter meetings, which begin this weekend in Anaheim.
This year's crop of Rule-5 eligibles is probably the strongest since I've been following it closely. There's usually a handful of promising relievers and raw arms to be sorted out, but this year there seems to be a little of everything. That'll make for an engaging round of selections. As you may know, if a team makes a Rule-5 selection, that player must remain on the active major league roster for the entire season, barring injury or front office-prompted malingering.