Ever since it began in the 1800s, baseball has been changing. It’s gone through times of drastic change, such as when they lowered the mound to end the dead ball era in 1969. But even when there hasn’t been something so drastic, players and coaches are always trying to find the upper edge.
In 2015, Statcast changed the way MLB teams look at baseball. The ever-growing database called Statcast tracks everything from pitch velocity, to spin rate, to exit velocity, sprint speed, and much more. This ever-widening wave of new information has created what is now referred to as the Statcast Revolution.
Over the course of this off-season, I will try to explain many of the new statistics that fans, players, and front offices are looking at. But to begin, I’m going to start with what I’ve called the “basic” stats.
Batting Average (BA)
Batting Average is one of the stats that has been around forever. It is just about the simplest stat that can be found. It’s so simple, in fact, that we can go back to the beginning of baseball and find a player’s batting average. The formula is as follows: HITS/AT BATS.
MLB defines a base hit (H) as any time a “batter strikes the baseball into fair territory and reaches base without doing so via an error or a fielder’s choice.” The four kinds of base hits are singles, doubles, triples, and home runs. Each kind counts as one hit in the Batting Average.
According to MLB, an at-bat (AB) occurs “when a batter reaches base via a fielder’s choice, hit or an error (not including catcher’s interference) or when a batter is put out on a non-sacrifice.” Basically, any plate appearance that doesn’t end in a walk, hit-by-pitch, or sacrifice counts as an at-bat.
For reference, a batting average of .300 is considered a Hall of Fame batting average. This means a batter who collects 3 hits in 10 at-bats (or fails in 7/10 at-bats) is considered good enough for the Hall of Fame. The better the batting average, the better. But batting average is also losing its draw. Players are now looking for power (homers and doubles) instead of singles.
On-Base Percentage (OBP)
Just like batting average, on-base percentage is a basic stat that measures how good a batter is. Instead of showing how often he collects base-hits, on-base percentage shows how good a hitter is at getting on base. In a slash-line, the on-base percentage comes second, right after batting average. The formula for OBP is pretty much as simple as batting average: (H + BB + HBP) / (AB + BB + HBP + SF). Another way of stating it could be times on base (excluding errors) / plate appearances.
Slugging Percentage (SLG)
While the first two stats in the slash line measure how often a player gets hits or reaches base, slugging percentage does not count all hits equally. Its goal has been to measure a hitters power, hence the name slugging percentage. But like many old-school stats, this one is not talked about as often as some of the newer stats invented by Statcast. The formula for Slugging Percentage is )1B + 2Bx2 + 3Bx3 + HRx4) / AB. Slugging percentage comes third in the slash-line.
The Slash-Line shows Batting Average, On-Base Percentage, and Slugging Percentage all at once. There is no additional math needed to find Slash-Line. It is written as BA/OBP/SLG. If a player’s Batting Average was .312, On-Base Percentage .460, and Slugging Percentage .628, his Slash-Line would be written as .312/.460/.628.
On-Base Plus Slugging (OPS)
On-base plus slugging, or OPS, as it is usually called, combines a hitter’s On-Base Percentage and Slugging Percentage into one stat. This helps to eliminate some of the errors found in the slash-line. OPS is found by using the following formula: OBP + SLG.
Total Bases (TB)
Total Bases is not used for measuring a player by himself, but it is used to help find stats to measure a player. Total Bases is just as simple as it sounds, the number of bases a player gains on hits. A single is worth one point, a double worth two, a triple worth three, and a home run worth four. Advancing on the bases or stealing a base does not add to a player’s total bases. The formula is 1B + 2Bx2 + 3Bx3 + HRx4. As you can see, this is the same thing as is used on the top line of SLG, which means SLG can also be written as TB / AB. Total Bases is also used in more advanced stats.