What Do Baseball Stats Mean?

A lot of people don’t understand what baseball stats mean. This blog post will help explain some of the more popular baseball stats and what they actually mean.

On-base percentage (OBP)

On-base percentage (OBP) is often called on-base average, and sometimes abbreviated as OB%, OBP, or OBA. This statistic measures the percentage of time a batter reaches base for any reason other than a fielding error or fielder’s choice. Times on base include hits, walks, hit by pitches, and reaching on an error.

A high on-base percentage is important because it allows a team to score runs without needing extra base hits. Players with a high OBP tend to be patient hitters, so they see a lot of pitches and as a result draw more walks. On-base percentage can also be applied to pitchers to measure how often they allow batters to reach base.

The league-average OBP in Major League Baseball has hovered between .320 and .330 for most of the last century. Anything above .400 is exceptional, and anything below .300 is poor. Famous examples of players with high OBPs include Babe Ruth, Ted Williams, Mickey Mantle, Willie Mays, and Barry Bonds.

Slugging percentage (SLG)

In baseball, slugging percentage (SLG) is a measure of the batting productivity of a hitter. It is calculated as total bases divided by at bats, through the following formula, where AB is the number of at bats for a given player, and 1B, 2B, 3B, and HR represent the number of singles, doubles, triples, and home runs hit:

SLG = (1B + 2×2B + 3×3B + 4×HR) / AB

For example, in 1980 George Brett had 139 hits including 46 doubles and 15 home runs. His slugging percentage was .664:

46+2×46+3×15= 320/490 = .664

Slugging percentage is generally considered to be more important than batting average because it is a better indicator of a player’s power.Walter Barnes wrote in 1911 that “batting average means so little or so much that it becomes utterly meaningless except in certain special cases.”

On-base plus slugging (OPS)

OPS is a way of combining a player’s on-base percentage and their slugging percentage. It is often considered to be a good measure of a player’s overall offensive ability, as it takes into account both their ability to get on base, as well as their power.

The formula for OPS is simple: you take a player’s on-base percentage and add their slugging percentage, and then multiply by 100. So, if a player has an OBP of .350 and a slugging percentage of .500, their OPS would be .850 (350 + 500 = 850, 850 x 100 = 85).

There are two main types of ops: OPS+ and wOBA. OPS+ is scaled to 100, with 100 being league average. So, if a player has an OPS+ of 110, that means they are 10% better than the league average hitter. wOBA is the more complicated of the two measures, but it essentially tries to measure how much a player contributes to their team’s offense on a per-plate appearance basis.

Earned run average (ERA)

In baseball, the earned run average (ERA) is themean of earned runs given up by a pitcher per nine inningspitched. The main use of ERA is to compare the effectivenessof pitchers in similar games. The lower the ERA, the betterthe pitcher is performing.

fielding percentage (FP)

Fielding percentage (FP) is calculated by dividing the number of putouts and assists by the number of total chances. It is considered to be one of the more important fielding statistics because it measures a player’s defensive consistency.

walks plus hits per inning pitched (WHIP)

Walks plus hits per inning pitched (WHIP) is a statistic in baseball used to measure a pitcher’s ability to prevent runners from achieving base hit. It combines a pitcher’s walks and hits allowed per inning pitched. The lower the WHIP, the better the performance.

batting average (AVG)

The batting average is the most common and basic baseball statistic. It is simply a hitter’s average number of hits per at-bat. The batting average does not take into account walks, hit by pitches, sacrifices, or times reached on an error. A .300 batting average is considered to be excellent.

home runs (HR)

A home run is a hit in baseball in which the batter scores by circling all the bases, ending at home plate, and achieving runner-to-catcher contact without stopping or being put out. In modern baseball, the feat is typically achieved by hitting the ball over the outfield fence between the foul poles without first touching the ground, resulting in an automatic home run. There is also the “inside-the-park” home run where the batter reaches home plate while still hitting the ball. A home run with a high exit velocity and good launch angle is sometimes called a “no-doubter,” because it leaves no doubt that it is going to leave the park when it comes off of the bat.