On-base percentage

History

The statistic was invented in the late 1940s by Brooklyn Dodgers statistician Allan Roth with then-Dodgers general manager Branch Rickey. In 1954, Rickey, who was then the general manager of the Pittsburgh Pirates, was featured in a Life Magazine graphic in which the formula for on-base percentage was shown as the first component of an all-encompassing "offense" equation. However, it was not named as on-base percentage, and there is little evidence that Roth's statistic was taken seriously at the time by the baseball community at large.

On-base percentage became an official MLB statistic in 1984. Its perceived importance jumped after the influential 2003 book Moneyball highlighted Oakland Athletics general manager Billy Beane's focus on the statistic. Many baseball observers, particularly those influenced by the field of sabermetrics, now consider on-base percentage superior to the statistic traditionally used to measure offensive skill, batting average, which accounts for hits but ignores other ways a batter can reach base.

Overview

Traditionally, players with the best on-base percentages bat as leadoff hitter, unless they are power hitters, who traditionally bat slightly lower in the batting order. The league average for on-base percentage in Major League Baseball has varied considerably over time; at its peak in the late 1990s, it was around .340, whereas it was typically .300 during the dead-ball era. On-base percentage can also vary quite considerably from player to player. The highest career OBP of a batter with more than 3,000 plate appearances is .482 by Ted Williams. The lowest is by Bill Bergen, who had an OBP of .194.

On-base percentage is calculated using this formula:

:OBP = \frac{H+BB+HBP}{AB+BB+HBP+SF}

where

• H = Hits
• BB = Bases on Balls (Walks)
• HBP = Hit By Pitch
• AB = At bat
• SF = Sacrifice fly

In certain unofficial calculations, the denominator is simplified and replaced by Plate Appearance (PA); however, the calculation PAs includes certain infrequent events that will slightly lower the calculated OBP (i.e. catcher's interference, and sacrifice bunts). Sacrifice bunts are excluded from consideration on the basis that they are usually imposed by the manager with the expectation that the batter will not reach base, and thus do not accurately reflect the batter's ability to reach base when attempting to do so. This is in contrast with the sacrifice fly, which is generally unintentional; the batter was trying for a hit.

All-time leaders

Single-season leaders

Notes

References

References

1. "Glossary / Standard Stats / On-base Percentage (OBP)". MLB.com.
2. "Yearly League Leaders & Records for On-Base%".
3. "What is a On-base Percentage (OBP)? {{!}} Glossary".
4. "Allan Roth – Society for American Baseball Research".
5. Rickey, Branch. (August 2, 1954). "Goodby to Some Old Baseball Ideas".
6. Schwarz, Alan. (2004). "The Numbers Game: Baseball's Lifelong Fascination with Statistics". St. Martin's Press.
7. (2009-05-23). "Prospectus Idol Entry: Why is On Base Percentage King?".
8. (16 November 2012). "My plea to mainstream on-base percentage instead of batting average".
9. (17 August 2017). "Stat to the Future: Why it's time to stop relying on batting average".
10. "OBP {{!}} Sabermetrics Library".
11. "Baseball reference: OBP".
12. Cole, Bryan. (2014-07-17). "Should the OBP formula include errors?".
13. "Fangraphs".
14. "Career Leaders for On Base Percentage". Sports Reference, Inc.
15. "Single Season League Leaders for On-Base Percentage". Sports Reference, Inc..