RBI

A run batted in (RBI), plural runs batted in (RBI or RBIs), is a statistic in baseball and softball that credits a batter for making a play that allows a run to be scored (except in certain situations like when an error is made on the play). For example, if the batter bats a base hit, then another player on a higher base can go home, and the batter gets credited with batting in that run.

Prior to the 1920 Major League Baseball season, runs batted in were not an official baseball statistic. Nevertheless, the RBI statistic was tabulated—unofficially—from 1907 through 1919 by baseball writer Ernie Lanigan, according to the Society for American Baseball Research.

Common nicknames for an RBI include "ribby", "rib", and "ribeye". The plural of RBI is generally "RBIs", although some commentators use "RBI" as both singular and plural, as it can also stand for "runs batted in".

The official rulebook of Major League Baseball states in Rule 10.04:

(a) The official scorer shall credit the batter with a run batted in for every run that scores:

(b) The official scorer shall not credit a run batted in

(c) The official scorer's judgment must determine whether a run batted in shall be credited for a run that scores when a fielder holds the ball or throws to a wrong base. Ordinarily, if the runner keeps going, the official scorer should credit a run batted in; if the runner stops and takes off again when the runner notices the misplay, the official scorer should credit the run as scored on a fielder's choice.

The perceived significance of the RBI is displayed by the fact that it is one of the three categories that comprise the triple crown. In addition, career RBIs are often cited in debates over who should be elected to the Hall of Fame. However, critics, particularly within the field of sabermetrics, argue that RBIs measure the quality of the lineup more than it does the player himself since an RBI can only be credited to a player if one or more batters preceding him in the batting order reached base (the exception to this being a solo home run, in which the batter is credited with driving himself in). This implies that better offensive teams—and therefore, the teams in which the most players get on base—tend to produce hitters with higher RBI totals than equivalent hitters on lesser-hitting teams.

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