A tale of two seasons

There was a recent thread on The Book blog about how to tell if a pitcher is any good. I recommend reading it if you haven’t already seen it. There isn’t anything groundbreaking, but the basic idea is that MGL goes through how uncertain the process really is, which plenty of people don’t seem to realize. Could we tell if John Smoltz was actually finished after his 40 innings with the Red Sox earlier this season? Red Sox Nation said he was, Nick Steiner, among others, said he wasn’t. Here’s the early returns: Stat nerds 1, RSN 0. But my point here is not to talk about John Smoltz.

My purpose here today is to talk about the two batting lines posted below the jump. Both are from exactly 50 games, but I extrapolated each one out to 150 games just so you can get a better feel for what all these numbers mean over a full season.

A: .340/.399/.716 (AVG/OBP/SLG), 19 HR, 51 RBI, 43 runs 13 2B, .454 wOBA (223 PA)
B: .222/.294/.418 (AVG/OBP/SLG), 8 HR, 28 RBI, 28 runs 14 2B, .290 wOBA (214 PA)

And here are those numbers extrapolated out to a full season of 150 games:
A150: .340/.399/.716 (AVG/OBP/SLG), 57 HR, 153 RBI, 129 runs 39 2B, .454 wOBA (223 PA)
B150: .222/.294/.418 (AVG/OBP/SLG), 24 HR, 84 RBI, 84 runs 42 2B, .290 wOBA (214 PA)

The first line is Babe Ruth-esque, the second line is more Rob Deer-ish. Stop me if you’ve seen this before… but both batting lines are from the same player. The first “player” is the batting line of Raul Ibanez from his first 50 games this season, the second line is from his next 50 games (he’s played in a convenient 100 games this season). The internet and media were both all abuzz this spring when Ibanez was on fire and was quasi-accused of being a steroid user. What if his last 50 games happened first and his first 50 games happened second? One, nobody would have ever mentioned Ibanez as a potential steroid user. Two, some internet writers (such as myself) might have continued to vilify Ruben Amaro for his atrocious signing.

Since we’re all pals here, let’s stick to number one, shall we? This is one of the issues that you can’t stress enough. Crazy things can happen when you have small sample sizes. You can not ignore them completely, but you have to look at small samples in the context of a much broader scope. After Raul’s terrible 50 game stretch of late, is there anyone out there saying he’s done as a professional baseball player? No. After all, he’s still having a career year. If he’s not done now, then he wasn’t Babe Ruth (or necessarily on steroids) his first 50 games. As good as he was playing then, and as bad as he’s playing now, he’s probably not either one. He’s somewhere in between, and that “somewhere” is pretty darn close to what he’s been doing the last few years in the major leagues.

He’s not a steroid user, nor is he a scrub. It’s that simple.