Friday Links
— My latest Huffington Post column is now up. I discuss why Wins shouldn’t be used to evaluate pitchers. So, kudos to Law and Carroll for using the right criteria for making their Cy Young picks. It’s fine to disagree with their choices, but the reasoning behind their decisions is much more sound than the reasoning used the chorus of sportswriters who are condemning them. — Rob Neyer disagrees with most of my

Cubs Sign Grabow
According to the Gordon Wittenmyer of the Chicago Sun-Times, the Cubs have agreed to a contract extension with John Grabow. It’s being reported to be for two years and for a total of “at least $7 million.” I’ve got him worth about $4 million over that span. I have to give this deal the thumbs down.

On Other Methods for Estimating Aging
My recent posts on my aging study have received a fair amount of criticism. There is no doubt that my study is imperfect, but all empirical researchers must make tradeoffs when selecting samples or choosing estimators. Small samples are sometimes preferred over large samples for expediency. Complicated models are sometimes necessary when simple methods mask biases. The goal of any researcher is to settle on a sample and method that

More on Player Aging
Phil Birnbaum has a new theory as to why I’m wrong (I suspect it won’t be his last), and he links to others who think I’ve made the same mistake. This time, my sample is the problem. By choosing a sample of players from 24 — 35 with a minimum of 10 seasons played and 5,000 plate appearances, this “biases” the estimates because I’ve chosen a sample that excludes people with short careers. To demonstrate this, Birnbaum simulates a new world to show that sample choice can affect estimated average peaks. This is irrelevant to what I have done,

How Do Players Age?
The last hot stove myth that I previously wrote about has to do with player aging. Players peak at 27 and old players are worthless — Players peak at 29 — 30. And just because a guy is past his peak doesn’t mean he’s not valuable. The aging process is gradual, more like the Minneapolis Metrodome than an Egyptian pyramid. If a guy was good last year, even if he’s in his mid-30s, he’ll probably be good next year. Now, the older he gets the more dangerous long-run contracts get, but one- and two-year deals are fine. This may not seem like much of a myth