Baseball is filled with stats, from the batting average you see on cards and in newspapers to the on-base percentage (OBP) you hear about on TV. These stats are meant to measure the performance of players over a career, but they do not always mean what you think they do. There are many factors that go into a game of baseball, from the ballpark to the weather and everything in between. But if you have the right information, you can get a better idea of the impact that each player has on their team’s success.
One of the most basic statistics is batting average, which measures how often a batter hits a home run, double or triple in each plate appearance. This number excludes any fielder’s choice or error, but does include walks and hit-by-pitch. This statistic is sometimes called on-base plus slugging (OPS) and some fans consider it to be a more complete measurement of a hitter’s abilities than batting average.
Another common baseball stat is earned run average, or ERA, which measures how many runs a pitcher allows in each inning pitched. This is counted in thirds, so if a pitcher pitches five innings and gets two outs in the sixth he is credited with 5 2/3 innings pitched.
Another important defensive stat is fielding percentage, or FPCT, which is calculated by dividing a player’s total chances to make a play on the ball by their actual number of successful plays. This includes puts outs and assists, as well as errors. It is a useful measure of a player’s ability to defend the position, but is also influenced by the ballpark and the situation in the game.