Yo! Stats. What is it all about? Technology. What is that all about? Is it good? Or is it wack?
-Ali G (sort of)
But before we dive into individual metrics, it’s important to go through the seemingly esoteric–yet important task of goal setting. What is our ultimate purpose for using stats? Here are two potential answers to this question:
- We use stats to quantify how much a player (or players) helped his team win baseball games
- We use stats to quantify how much a player (or players) will help his team win baseball games
This distinction is a lot more than figuring out what the definition of “is” is. These are two fundamentally different questions, and we need to decide on where we’re going before we actually get anywhere.
Each of the goals I posed leads to a different approach to using and applying stats. The first definition is backward looking. It looks at what already happened. This is the more simple and straightforward approach.
You might have at one time heard someone say something like “RBIs are the most important stat in baseball because runs are what win games. You can’t have runs without RBIs.” To address that guy, let’s look at a simple, common example:
We know a dude was on base when a bro was up to bat. We know the bro hit the ball in such a way that the dude scored. By doing so, the bro helped his team win a baseball game.
Now here’s another example: suppose a bro came up to bat 5 times with a dude on base 5 times in one game and achieved 1 hit. But a brah came up to bat 5 times with no one on base and got 3 hits.
Each batter had no control over whether a runner was on base. However both players had a good deal of control over whether they got hits. If we didn’t know anything else about the players, we could say that the bro helped his time win this baseball game more. But because he got more hits, the brah is likely the better hitter. And the better hitter, again all else equal, will help his team win more games in the future.
The plan of attack then becomes twofold:
- Figure out which baseball player is responsible for which baseball thing
- Figure out how much that baseball thing helps that baseball player’s team win more baseball games
I look forward to getting dirty with everyone as the series go on. If you’re interested in diving in early, I’m certainly not the first to tackle this subject. Alex Remington has a similar series at Yahoo! Sports and Fangraphs has an excellent glossary. I hope to take a streamlined approach to this process compared to what’s already out there, sacrificing some detail in the process. In exchange, the plan is to keep each discussion as digestible as possible. As such I’d love your feedback and any extra info you think is important in the comments of this post and future posts.