Hokey smokes, I haven't blogged here since the end of 2015? That changes now.
Actually, I've had a somewhat busy winter, publishing-wise, just not here. Let me bring you up to date.
In October, I wrote about how the American League in 2015 had the greatest parity, measured by the standard deviation of wins among its teams, in major league history. FanGraphs link here, Banished to the Pen link here.
In December, I noted that four teams in 2015--the Pirates, Yankees, Nationals, and Phillies--had two catchers account for at least 98.5% of the innings caught by their teams, so their team didn't have to rely on a third catcher. Such teams, since 1969, have averaged 85 wins per season. Unfortunately, the trend doesn't appear to be durable. the 236 teams with just two players dominating catching chores one season, only 25% were able to repeat the feat the next year. FanGraphs link here, Banished to the Pen link here.
Still in December, I did an analysis of every batter hit by a pitch in a Pirates game last year. There were a lot, given that the Bucs led the league in both hit batters (75) and getting hit by pitches (89). I found no evidence that the hit batters followed a general pattern of retaliation, i.e., you hit my guy, I hit yours. FanGraphs link here, Banished to the Pen link here.
Also in December, I discovered that hitters who changed their approach at the plate by pulling the ball a lot more or a lot less, or hitting it on the ground a lot more or a lot less, did better in 2015 relative to batters who hit more the same. But when the difference is generated by a lot more or a lot less of an action, it doesn't really suggest that, e.g., a batter would hit better by going the other way. FanGraphs link here, Banished to the Pen link here.
In the new year, I discovered that players 35+ are slowing down--exhibiting worse batting skills as they age--faster than in the past. The reasons, I hypothesized, are PED and amphetamine testing, faster fastballs, and managers' insistence on keeping high-paid veterans in the lineup. FanGraphs link here, Banished to the Pen link here.
Also in January, I discovered that while on base percentage has been in vogue since the publication of Moneyball, slugging percentage is better correlated to run production than on base percentage. And don't even think about batting average. FanGraphs link here, Banished to the Pen link here.
And that doesn't even cover my big winter project. I'll get to that tomorrow.