HOME

TheInfoList



OR:

Sabermetrics (originally SABRmetrics) is the original or blanket term for
sports analytics Sports analytics are collections of relevant historical statistics that can provide a competitive advantage to a team or individual by helping to inform players, coaches and other staff and help facilitate decision-making both during and prior to s ...
in the US, the
empirical Empirical evidence is evidence obtained through sense experience or experimental procedure. It is of central importance to the sciences and plays a role in various other fields, like epistemology and law. There is no general agreement on how t ...
analysis of
baseball Baseball is a bat-and-ball games, bat-and-ball sport played between two team sport, teams of nine players each, taking turns batting (baseball), batting and Fielding (baseball), fielding. The game occurs over the course of several Pitch ...
, especially the development of
advanced metrics Sports analytics are collections of relevant historical statistics that can provide a competitive advantage to a team or individual by helping to inform players, coaches and other staff and help facilitate decision-making both during and prior to s ...
based on
baseball statistics Baseball statistics include a variety of metrics used to evaluate player and team performance in the sport of baseball. Because the flow of a baseball game has natural breaks to it, and player activity is characteristically distinguishable ind ...
that measure in-game activity. The term is derived from the movement's progenitors, members of the
Society for American Baseball Research The Society for American Baseball Research (SABR) is a membership organization dedicated to fostering the research and dissemination of the history and statistical record of baseball. The organization was founded in Cooperstown, New York, on Au ...
(SABR), founded in 1971, and was coined by
Bill James George William James (born October 5, 1949) is an American baseball writer, historian, and statistician whose work has been widely influential. Since 1977, James has written more than two dozen books about baseball history and statistics. His a ...
, (in 1980, according to SABR.org), who is one of its pioneers and considered its most prominent advocate and public face. The term moneyball refers to the use of metrics to identify "undervalued players" and sign them to what ideally will become "below market value" contracts; it began as an effort by small-market teams to compete with the much greater resources of big-market ones.


Early history

English-American sportswriter Henry Chadwick developed the
box score A box score is a structured summary of the results from a sport competition. The box score lists the game score as well as individual and team achievements in the game. Among the sports in which box scores are common are baseball, basketball, A ...
in New York City in 1858. This was the first way statisticians were able to describe the sport of baseball by numerically tracking various aspects of game play. The creation of the box score has given baseball statisticians a summary of the individual and team performances for a given game. What would become the earliest Sabermetrics research in the 1970s and 1980s began in the middle of the 20th century with the writings of
Earnshaw Cook Earnshaw Cook (March 28, 1900 – November 11, 1987) was an American early researcher and proponent of sabermetrics, the analysis of baseball through statistical means. Engineering Cook was born in Reisterstown, Maryland in 1900. A member of the ...
, one of the earliest baseball analysts. Cook's 1964 book ''Percentage Baseball'' was one of the first of its kind. At first, most organized baseball teams and professionals dismissed Cook's work as meaningless. The idea of a science of baseball statistics began to achieve legitimacy in 1977 when
Bill James George William James (born October 5, 1949) is an American baseball writer, historian, and statistician whose work has been widely influential. Since 1977, James has written more than two dozen books about baseball history and statistics. His a ...
began releasing ''Baseball Abstracts'', his annual compendium of baseball data. However, James's ideas were slow to find widespread acceptance. Bill James believed there was a widespread misunderstanding about how the game of baseball was played, claiming the sport was not defined by its rules but actually, as summarized by engineering professor Richard J. Puerzer, "defined by the conditions under which the game is played – specifically, the ballparks but also the players, the ethics, the strategies, the equipment, and the expectations of the public." Early Sabermetricians – sometimes considered baseball statisticians – began trying to enhance such fundamental baseball statistics as
batting average Batting average is a statistic in cricket, baseball, and softball that measures the performance of batters. The development of the baseball statistic was influenced by the cricket statistic. Cricket In cricket, a player's batting average is ...
(simply hits divided by at-bats) with advanced mathematical formulations. The correlation between team batting average and runs scored was also examined, as runs – not hits – win ballgames. Thus, a good measure of a player's worth would be his ability to help his team score runs, which was observed to be highly correlated with his number of times on base – leading to the development of a new stat, "on-base percentage". Before Bill James popularized sabermetrics, Davey Johnson, then a second baseman playing for the early 1970s
Baltimore Orioles The Baltimore Orioles (also known as the O's) are an American professional baseball team based in Baltimore. The Orioles compete in Major League Baseball (MLB) as a member club of the American League (AL) East Division. As one of the America ...
of
Major League Baseball Major League Baseball (MLB) is a professional baseball league composed of 30 teams, divided equally between the National League (baseball), National League (NL) and the American League (AL), with 29 in the United States and 1 in Canada. MLB i ...
(MLB), used an
IBM System/360 The IBM System/360 (S/360) is a family of mainframe computer systems announced by IBM on April 7, 1964, and delivered between 1965 and 1978. System/360 was the first family of computers designed to cover both commercial and scientific applicati ...
at team owner
Jerold Hoffberger Jerold Charles Hoffberger (April 7, 1919 – April 9, 1999) was an American businessman. He was president of the National Brewing Company from 1946 to 1973. He was also part-owner of the Baltimore Orioles of the American League from 1954 t ...
's brewery to write a FORTRAN-based baseball
computer simulation Computer simulation is the running of a mathematical model on a computer, the model being designed to represent the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be determin ...
. In spite of his results, he was unable to persuade his manager
Earl Weaver Earl Sidney Weaver (August 14, 1930 – January 19, 2013) was an American professional baseball manager, author, and television broadcaster. After playing in minor league baseball, he retired without playing in Major League Baseball (MLB). He be ...
that he should bat second in the lineup. He wrote
IBM BASIC The IBM Personal Computer BASIC, commonly shortened to IBM BASIC, is a programming language first released by IBM with the IBM Personal Computer, Model 5150 (IBM PC) in 1981. IBM released four different versions of the Microsoft BASIC interprete ...
programs to help him manage the
Tidewater Tides The Norfolk Tides are a Minor League Baseball team of the International League and the Triple-A affiliate of the Baltimore Orioles. They are located in Norfolk, Virginia, and are named in nautical reference to the city's location on the Chesape ...
, and after becoming manager of the
New York Mets The New York Mets are an American professional baseball team based in the Boroughs of New York City, New York City borough of Queens. The Mets compete in Major League Baseball (MLB) as a member club of the National League (baseball), National ...
in 1984, he arranged for a team employee to write a
dBASE II dBase (also stylized dBASE) was one of the first database management systems for microcomputers and the most successful in its day. The dBase system included the core database engine, a query system, a forms engine, and a programming languag ...
application to compile and store
advanced metrics Sports analytics are collections of relevant historical statistics that can provide a competitive advantage to a team or individual by helping to inform players, coaches and other staff and help facilitate decision-making both during and prior to s ...
on team statistics. Craig R. Wright was another employee in MLB, working with the Texas Rangers in the early 1980s. During his time with the Rangers, he became known as the first front office employee in MLB history to work under the title "sabermetrician". David Smith founded
Retrosheet Retrosheet is a 501(c)(3) non-profit organization whose website features box scores of Major League Baseball (MLB) games from 1906 to the present, and play-by-play narratives for almost every contest since the 1930s. It also includes scores fr ...
in 1989, with the objective of computerizing the box score of every major league baseball game ever played, in order to more accurately collect and compare the statistics of the game. The
Oakland Athletics The Oakland Athletics (frequently referred to as the Oakland A's) were an American Major League Baseball (MLB) team based in Oakland, California from 1968 to 2024. The Athletics were a member club of the American League (AL) American League We ...
began to use a more quantitative approach to baseball by focusing on sabermetric principles in the 1990s. This initially began with
Sandy Alderson Richard Lynn "Sandy" Alderson (born November 22, 1947) is an American baseball executive. He was the president of various Major League Baseball teams, including the New York Mets. He previously served as the general manager of the New York Mets f ...
as the
general manager A general manager (GM) is an executive who has overall responsibility for managing both the revenue and cost elements of a company's income statement, known as profit & loss (P&L) responsibility. A general manager usually oversees most or all of ...
of the team when he used the principles toward obtaining relatively undervalued players. His ideas were continued when
Billy Beane William Lamar Beane III (born March 29, 1962) is an American former professional baseball player and current Front office (sports), front office executive. He is currently senior advisor to owner John Fisher (baseball owner), John Fisher and ...
took over as general manager in 1997, a job he held until 2015, and hired his assistant
Paul DePodesta Paul DePodesta (born December 16, 1972) is an American football executive and former baseball executive who is the chief strategy officer of the Cleveland Browns of the National Football League (NFL). He previously served as a front office assist ...
. During the 2002 season, a noted "moneyball" Oakland A's team went on to win 20 games in a row, a term (and approach to the game) which soon gained national recognition when
Michael Lewis Michael Monroe Lewis (born October 15, 1960) Gale Biography In Context. is an American author and financial journalist. He has also been a contributing editor to '' Vanity Fair'' since 2009, writing mostly on business, finance, and economics. ...
published '' Moneyball: The Art of Winning an Unfair Game'' (where "unfair" reflected the disparity in resources available to the big market teams versus the small) in 2003 to detail Beane's use of advanced metrics. In 2011, a film based on Lewis' book – also called ''
Moneyball Moneyball or money ball may refer to: * '' Moneyball: The Art of Winning an Unfair Game'', 2003 book by Michael Lewis ** ''Moneyball'' (film), 2011 film adaptation of the book * ''Moneyball'' (album), 2025 album by Dutch Interior * Sabermetrics ...
–'' was released and gave broad exposure to the techniques used in the Oakland Athletics' front office.


Traditional measurements

Sabermetrics reflected a desire by a handful of baseball enthusiasts to expand their understanding of the game by revealing new insights that may have been hidden in its traditional statistics. Their early efforts ultimately evolved into evaluating players in every aspect of the game, including batting, pitching, baserunning, and fielding.


Batting measurements

A ballplayer's
batting average Batting average is a statistic in cricket, baseball, and softball that measures the performance of batters. The development of the baseball statistic was influenced by the cricket statistic. Cricket In cricket, a player's batting average is ...
(BA) (simply
hits Hits or H.I.T.S. may refer to: Arts, entertainment, and media Music * '' H.I.T.S.'', 1991 album by New Kids on the Block * ''...Hits'' (Phil Collins album), 1998 * ''Hits'' (compilation series), 1984–2006; 2014, a British compilation album s ...
divided by
at-bats In baseball, an at bat (AB) or time at bat is a batter's turn batting against a pitcher. An at bat is different from a plate appearance. A batter is credited with a plate appearance regardless of what happens upon completion of his turn at bat, b ...
) was the historic measure of a player's offensive performance, enhanced by
slugging percentage In baseball statistics, 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, an ...
(SA) which incorporated their ability to hit for power. Bill James, along with other early sabermetricians, was concerned that batting average did not incorporate other ways a batter can reach base besides a hit – as a batter on base can score runs, and runs, not hits, win ballgames. Even though slugging percentage and an early form of
on-base percentage In baseball statistics, on-base percentage (OBP) measures how frequently a batting (baseball), batter reaches base (baseball), base. An official Major League Baseball (MLB) statistic since 1984, it is sometimes referred to as on-base average (OBA ...
(OBP) – which takes into accounts base on balls ("walks") and hit-by-pitches – date to at least 1941, pre-dating both Bill James (born 1949) and SABR (formed 1971), enhanced focus was put on the relationship of times on base and run scoring by early SABR-era baseball statistical pioneers. SA and OBP were combined to create the modern statistic
on-base plus slugging On-base plus slugging (OPS) is a sabermetric baseball statistic calculated as the sum of a player's on-base percentage and slugging percentage. The ability of a player both to get on base and to hit for power, two important offensive skills, are ...
(OPS). OPS is the sum of the on-base percentage and the slugging percentage. This modern statistic has become useful in comparing players and is a powerful method of predicting runs scored by any given player. An enhanced version of OPS, "OPS+", incorporates OPS, historic statistics, ballpark considerations, and defensive position weightings to attempt to allow player performance from different eras to be compared. Some other advanced metrics used to evaluate batting performance are
weighted on-base average In baseball, wOBA (or weighted on-base average) is a statistic, based on linear weights, designed to measure a player's overall offensive contributions per plate appearance. It is formed from taking the observed run values of various offensive ev ...
, secondary average,
runs created Runs created (RC) is a baseball statistics, baseball statistic invented by Bill James to estimate the number of runs a hitter contributes to their team. Purpose James explains in his book, ''The Bill James Historical Baseball Abstract'', why he be ...
, and equivalent average.


Pitching measurements

The traditional measure of pitching performance is the
earned run average In baseball statistics, earned run average (ERA) is the average of earned runs allowed by a pitcher per nine innings pitched (i.e. the traditional length of a game). It is determined by dividing the number of earned runs allowed by the number ...
(ERA). It is calculated as
earned run In baseball, an earned run is any run that was fully enabled by the offensive team's production in the face of competent play from the defensive team. Conversely, an unearned run is a run that would not have been scored without the aid of an erro ...
s allowed per nine innings. Earned run average does not separate the ability of the pitcher from the abilities of the fielders that he plays with. Another classic measure for pitching is a pitcher's
winning percentage In sports, a winning percentage or Copeland score is the fraction of games or matches a team or individual has won. The statistic is commonly used in standings or rankings to compare teams or individuals. It is defined as wins divided by the to ...
. Winning percentage is calculated by dividing wins by the total number of decisions (wins plus losses). Winning percentage is also heavily dependent on the pitcher's team, particularly on the number of runs it scores. Sabermetricians have attempted to find different measures of pitching performance that exclude the performances of the fielders involved. One of the earliest developed, and one of the most popular in use, is
walks plus hits per inning pitched In baseball statistics, walks plus hits per inning pitched (WHIP) is a Sabermetrics, sabermetric measurement of the number of Baserunning#Becoming a runner, baserunners a pitcher has allowed per Innings pitched, inning pitched. WHIP is calculate ...
(WHIP), which while not completely defense-independent, tends to indicate how many times a pitcher is likely to put a player on base (either via walk, hit-by-pitch, or base hit) and thus how effective batters are against a particular pitcher in reaching base. A later development was the creation of
defense independent pitching statistics In baseball, fielding independent pitching (FIP) (also referred to as defense independent pitching (DIP)) is intended to measure a pitcher's effectiveness based only on statistics that do not involve fielders (except the catcher). These include ho ...
(DIPS) system. Voros McCracken has been credited with the development of this system in 1999. Through his research, McCracken was able to show that there is little to no difference between pitchers in the number of hits they allow on balls put into play – regardless of their skill level. Some examples of these statistics are defense-independent ERA, fielding independent pitching, and
defense-independent component ERA Defense-Independent Component ERA (DICE) is a 21st-century variation on Component ERA, one of an increasing number of baseball sabermetrics that fall under the umbrella of defense independent pitching statistics. DICE was created by Clay Dreslou ...
. Other sabermetricians have furthered the work in DIPS, such as Tom Tango who runs the ''Tango on Baseball'' sabermetrics website. ''
Baseball Prospectus Baseball Prospectus (BP) is an organization that publishes a website, BaseballProspectus.com, devoted to the sabermetric analysis of baseball. BP has a staff of regular columnists and provides advanced statistics as well as player and team perf ...
'' created another statistics called the
peripheral ERA Peripheral ERA (PERA) is a pitching statistic created by the Baseball Prospectus team. It is the expected earned run average taking into account park-adjusted hits, walks, strikeouts, and home runs allowed. Unlike Voros McCracken's DIPS, hits a ...
. This measure of a pitcher's performance takes hits, walks, home runs allowed, and strikeouts while adjusting for ballpark factors. Each ballpark has different dimensions when it comes to the outfield wall so a pitcher should not be measured the same for each of these parks. Batting average on balls in play (BABIP) is another useful measurement for determining pitchers' performance. When a pitcher has a high BABIP, they will often show improvements in the following season, while a pitcher with low BABIP will often show a decline in the following season. This is based on the statistical concept of
regression to the mean Regression or regressions may refer to: Arts and entertainment * ''Regression'' (film), a 2015 horror film by Alejandro Amenábar, starring Ethan Hawke and Emma Watson * ''Regression'' (magazine), an Australian punk rock fanzine (1982–1984) * ...
. Others have created various means of attempting to quantify individual pitches based on characteristics of the pitch, as opposed to runs earned or balls hit.


Advanced methods

Value over replacement player (VORP) This statistic attempts to demonstrate how much a player contributes to his team in comparison to a hypothetical player performing at the minimum level needed to hold a roster position on a major league team. It was invented by Keith Woolner, a former writer for the sabermetric group/website ''Baseball Prospectus''. Wins above replacement (WAR) is another popular sabermetric statistic for evaluating a player's contributions to his team. Similar to VORP, WAR compares a given player to a replacement-level player in order to determine the number of additional wins the player provides to his team relative to an average ballplayer at his position. WAR, like VORP a ''cumulative'' statistic, heavily reflects the amount of a player's playing time. "Static" statistics based on simple ratios of already accumulated data (like batting average) and accumulative tallies (such as pitching wins) do not fully reveal all aspects of the game represented in their numeric totals. Advanced metrics are increasingly developed and targeted to addressing ''in-game'' activities (such as when a team should attempt to steal a base, and when to bring closers in).


Applications

Sabermetrics are commonly used for everything from sportswriting to baseball Hall of Fame consideration, selecting player match-ups and evaluating in-game strategic options. Advanced statistical measures may be utilized in determining in-season and end-of-the-season awards (such as Player of the Week and MVP). Those which are most useful in evaluating past performance and predicting future outcomes are valuable in determining a player's contributions to his team, potential trades, contract negotiations, and arbitration. Recently, sabermetrics has been expanded to examining ballplayer minor league performance in AA and AAA ball in a manner similar to evaluating it at the Major League level, known as Minor-League Equivalency.


Advancements since 1985

Bill James' two books, ''
The Bill James Historical Baseball Abstract ''The Bill James Historical Baseball Abstract'' is a reference book written by Bill James featuring an overview of professional baseball Baseball is a bat-and-ball games, bat-and-ball sport played between two team sport, teams of nine ...
'' (1985) and '' Win Shares'' (2002) have continued to advance the field of sabermetrics. The work of his former assistant Rob Neyer, who later became a senior writer at ESPN.com and national baseball editor of SBNation, also contributed to popularizing sabermetrics since the mid-1980s.
Nate Silver Nathaniel Read Silver (born January 13, 1978) is an American statistician, political analyst, author, sports gambler, and poker player who Sabermetrics, analyzes baseball, basketball and Psephology, elections. He is the founder of ''FiveThirty ...
, a former writer and managing partner of ''Baseball Prospectus'', invented
PECOTA PECOTA, an acronym for ''Player Empirical Comparison and Optimization Test Algorithm'', is a sabermetric system for forecasting Major League Baseball player performance. The word is a backronym based on the name of journeyman major league player B ...
(''Player Empirical Comparison and Optimization Test Algorithm'') in 2002–2003, introducing it to the public in the book ''Baseball Prospectus'' in 2003. It assumes that the careers of similar players will follow a similar trajectory. Beginning in the 2007 baseball season, MLB started looking at technology to record detailed information regarding each pitch that is thrown in a game. This became known as the PITCHf/x system, which uses video cameras to record pitch speed at its release point and crossing the plate, location, and angle (if any) of a break.
FanGraphs FanGraphs.com is a website run by Fangraphs Inc., located in Arlington, Virginia, and created and owned by David Appelman that provides statistics for every player in Major League Baseball history. On September 18, 2009, Fangraphs Inc. launched ...
is a website that utilizes this information and other play-by-play data to publish advanced baseball statistics and graphics.


In popular culture

* ''
Moneyball Moneyball or money ball may refer to: * '' Moneyball: The Art of Winning an Unfair Game'', 2003 book by Michael Lewis ** ''Moneyball'' (film), 2011 film adaptation of the book * ''Moneyball'' (album), 2025 album by Dutch Interior * Sabermetrics ...
'', the 2011 film about
Billy Beane William Lamar Beane III (born March 29, 1962) is an American former professional baseball player and current Front office (sports), front office executive. He is currently senior advisor to owner John Fisher (baseball owner), John Fisher and ...
's use of sabermetrics to build the
Oakland Athletics The Oakland Athletics (frequently referred to as the Oakland A's) were an American Major League Baseball (MLB) team based in Oakland, California from 1968 to 2024. The Athletics were a member club of the American League (AL) American League We ...
. The film is based on
Michael Lewis Michael Monroe Lewis (born October 15, 1960) Gale Biography In Context. is an American author and financial journalist. He has also been a contributing editor to '' Vanity Fair'' since 2009, writing mostly on business, finance, and economics. ...
's book of the same name. * In the television show ''
Numb3rs ''Numbers'' (stylized as ''NUMB3RS'') is an American crime drama television series that originally aired on CBS from January 23, 2005, to March 12, 2010, with a total of six seasons consisting of 118 episodes. The series was created by Nico ...
'', the season 3 episode "Hardball" focuses on sabermetrics, and the season 1 episode "Sacrifice" also covers the subject. * " MoneyBART", the third episode of ''
The Simpsons ''The Simpsons'' is an American animated sitcom created by Matt Groening and developed by Groening, James L. Brooks and Sam Simon for the Fox Broadcasting Company. It is a Satire (film and television), satirical depiction of American life ...
'' 22nd season, in which
Lisa Lisa or LISA may refer to: People People with the mononym * Lisa (Japanese musician, born 1974), stylized "LISA" * Lisa, stagename of Japanese singer Lisa Komine (born 1978) * Lisa (South Korean singer) (born 1980) * Lisa (Japanese musician, b ...
utilizes sabermetrics to coach Bart's Little League Baseball team.


See also

* Analytics (ice hockey), the ice hockey equivalent * Advanced statistics in basketball, the basketball equivalent *
Fielding Bible Award A Fielding Bible Award recognizes the best defensive player for each baseball positions, fielding position in Major League Baseball (MLB) based on "statistical analysis, the eye test, and any other factors that anelistswish to utilize." John D ...
* Kyle Boddy, founder of Driveline Baseball * Statcast * ''
The Hardball Times The Hardball Times (abbreviated as THT) is a website which publishes news, original comments and statistical analysis of baseball each week Monday through Friday, in addition to the Hardball Times Annual book which features essays by leading sabe ...
'' * Theorycraft * ''
Total Baseball ''Total Baseball'' is a 2,301-page baseball encyclopedia first compiled by John Thorn and Pete Palmer in 1989. By its fourth edition, Major League Baseball endorsed it as its official encyclopedia. The encyclopedia contains seasonal and career sta ...
'' by
John Thorn John Abraham Thorn (born April 17, 1947) is a German-born American sports historian, author, and publisher. Since 2011, he has served as the Official Baseball Historian for Major League Baseball. Early life Thorn was born in Stuttgart, Germany ...
and
Pete Palmer Pete Palmer (born January 30, 1938) is an American sports statistician and encyclopedia editor. He is a major contributor to the applied mathematical field referred to as sabermetrics. Along with the Bill James '' Baseball Abstracts'', Palmer's ...
* '' Whatever Happened to the Hall of Fame?'' by Bill James


Notes


References


External links


Society for American Baseball Research
(SABR) {{Sports rating systems Baseball statistics Baseball strategy Bill James Sports science Society for American Baseball Research