If you’ve followed baseball a bit over the last ten or twenty years, you might’ve heard a term bandied (and in some cases, ridiculed) called sabremetrics. You might even hear more about the term creep into the media since Michael Lewis’s book “Moneyball” is scheduled to hit the big screen on September 23rd starring Brad Pitt. Yet you might still wonder what it is, why people care, and how much of it is “much ado about nothing”.

Sabremetrics is, to put it simply, the study of the measurable elements of the game of baseball. In other words, you got a group of people who really love baseball and for fun (and in recent years, as a career), dive as deep as they can into the bits and pieces of the game to figure part of it out. Just as there are people who try to predict the stock market or to figure out how to build a better mouse trap and what parts of a mouse trap are better than others, sabremetricians try to find concrete evidence in baseball. Now, that isn’t a really easy thing to do. Sure, baseball as elements of the hard sciences such as physics, geometry and mathematics. Yet, it’s also a game played by people and the best player in the world can strike out four times in a row or the best pitcher can have problems finding the strike zone with a GPS and a trebuchet on a given day. Then, think of all the things not in a typical physics equation that can fiddle with a baseball thrown to the plate like how the wind speed and humidity can flatten a curveball in Colorado and sabremetricians got a lot of noise that they have to wade through. And that’s even before “lucK” tosses a wrench in the equation!

So what are some of the concepts that sabremetricians use? Well, since sabremetricians try to study what they can measure (with some reliability), what they do is break the events in baseball down to a series of events that have a chance of leading to a subsequent set of events. As an example, sabremetricians try to calculate if a player gets on first base, what would be their chance to score? How does their chance to score change with one out in the inning? What if there is one out with a left-handed groundball pitcher throws against a right-handed flyball hitter when the infield is shifted to the third base side? Sabremetricians can get even deeper into the scenarios and the probabilities of certain outcomes than that, but you get the idea.

One fundamental concept of sabremetrics and probabilities is that a team that scores more runs than it allows is more likely to win more games than it loses. Sounds pretty simple, right? Yet, tt wasn’t always something that was regularly thought about. Bill James, one of the forefathers of sabremetrics, popularized that insight (along with many others) around thirty years ago. If you ever check the baseball standings and see run differential, represented as the difference between runs scored and runs allowed, you can thank him for that. What made him so innovative was that he asked simple questions that challenged “common knowledge” assumptions and went about trying to find answers to those questions. In turn, he’d publish what he found in “The Bill James Baseball Abstract” and encourage others to look into what he was investigating. Thus, more people asking more questions lead to more knowledge about baseball. In case you’re wondering, he’s been working for the Red Sox since 2003 and while he obviously can’t claim all the credit for breaking the Babe’s curse, it’s very possible his insight on baseball has helped turn the Red Sox into a winning team.

If you want to talk about the importance of runs, you also need to talk about the components that make up runs. Sabremetrics, in recent years, has helped to look closer at those elements. If you looked on the backs of most baseball cards and in most baseball yearbooks before this millenium, the statistics you would see for a player would be their batting average, runs, home runs and runs batted in. Until sabremetrics, there was little true appreciation of how much walks helped an offense no matter how many times the adage “a walk is as good as a hit” was repeated ad nauseam by Little League coaches across America. Heck, some major league hitters would even get chastized for taking a walk.. even by some of the players-turned-broadcasters who were valued by sabremetricians precisely for their ability to get on base! Nowadays, the value of a walk has gone more mainstream and you can find on-base percentage and walks included in box scores and television broadcasts.

On the flipside, the perspective on what components make a good pitcher have also changed. It used to be that wins and ERA were the only factors that mattered when evaluating Cy Young Award candidates. Nowadays, ERA has diminished in importance among the sabremetric community. Research by Voros McCracken and others suggest that a pitchers tend to have some control over their walk rates, their strikeout rates and their home runs allowed. Whether batted balls that are not home runs are converted into outs are more dependent on a team’s defense than a particular skill the pitcher has besides, perhaps groundball/flyball ratio. This increased understanding of what pitchers can influence has permeated through mainstream baseball thought, to the point where the voters in 2010 awarded Felix Hernandez the Cy Young Award though he won only thirteen games and was only one game over .500 (13-12). Why did he win? Because he was a monster at preventing runners from reaching base but received so few wins because of the anemic offensive performance of the Seattle Mariners offense.

Another nice thing about sabremetrics is it makes it possible to compare players from different parks, leagues, eras and even competition levels. WHen new innovations come to sabremetrics, they are often applied to past years to arrive at new insights. Baseball is a great game for that because, to paraphase Kevin Costner from “For the Love of the Game”, they count everything in baseball and those counts can always be reevaluated and put into a new context. Tools like Pitch Fx can tell you about the movement and velocity of a pitcher’s pitches in such a way that you can see how a Stephen Strasburg fastball differs from Aroldis Champan’s. There are projection systems to predict what major league players would do like PECOTA and Marcel. You can even use Brian Cartwright’s Oliver projection system to look at Japanese, Korean, semi-pro, Cape Code and college leagues and estimate how those  players would perform if they were in the major leagues.

As sabremetricians identify components to scoring runs and winning games, they developed the idea of a replacement-level player to measure the talent on a given major league roster. A replacement-level player is basically a freely available Triple-A talent that any team could acquire for cheap. The idea is to identify players who provide as much value to your team as possible above replacement level with as low of a cost as possible. Measurement tools such as EqA, VORP and WAR all are used in such a fashion and can even be used to see if a pitcher is more valuable than a hitter or vice versa. Besides identifying value, keeping costs low can also be used to get the most “bang for your buck”. This concept was most illustrated in Moneyball where Oakland A’s GM Billy Beane had to figure out how to field a competitive team with a small payroll. To do so, he utilized sabremetrics to find market inefficiencies in how the rest of baseball evaluated players and used those efficiencies to acquire players who could provide as much value as possible for as cheaply as possible.

Yet, beyond increasing our understanding of baseball, the best aspects of sabremetrics are that it encourages passionate discussion among fans about the game, then provides those fans a framework to do their own research. Ever wonder if a certain pitcher is injured? You can look at the velocity and movement of his pitches for a clue. Do you really think Hank Aaron was better than Babe Ruth? Sabremetrics gives you tools to do comparisons. Just like a baseball commentator during a game or comparing the backs of baseball cards with your friends, sabremetrics provides just one more way of looking at players and thus, another way to appreciate the game.

So how do you get started? Browse the web. They’re all out there. Pick a name from this post and look up some of what they have written. Check out some of the baseball links on the right hand side of this post and click on any article you find there that looks interesting. Go to google and look up a term like WAR or on-base percentage. Take a peek and you might just see something about baseball you didn’t before. And once you do, make sure to tell your friends!