Defense independent pitching statistics
Encyclopedia
In baseball
, defense-independent pitching statistics (DIPS) measure a pitcher's effectiveness based only on plays that do not involve fielders: home run
s allowed, strikeout
s, hit batters
, walks
, and, more recently, fly ball percentage, ground ball percentage, and (to much a lesser extent) line drive percentage. Those plays are under only the pitcher's control in the sense that fielders (not including the catcher) have no effect on their outcome.
Several sabermetric
methods use only these "defense-independent" pitching statistics to evaluate a pitcher's ability. The logic behind using only these statistics is that once a ball is put in play, most often the pitcher has no effect on the resultant fielding of the ball. But defense-dependent statistics, such as the rate of hits allowed on balls put into play, are sometimes affected by the quality and/or arrangement of the defense behind the pitcher. For example, an outfielder may make an exceptionally strong diving catch to prevent a hit, or a base runner may beat a play to a base on a ball thrown from a fielder with sub par arm strength. Defense-independent statistics such as walks and strikeouts are determined almost solely by the pitcher's ability level.
While the creators of DICE, FIP and similar statistics all suggest they are "defense independent", others have pointed out that their formulas involve innings pitched(IP). Innings pitched is a statistical measure of how many outs were made while a pitcher was pitching. This includes those made by fielders who are typically involved in more than two thirds of the outs. These critics claim this makes pitchers' DICE or FIP highly dependent on the defensive play of their fielders.
In 1999, Voros McCracken
became the first to detail and publicize these effects to the baseball research community when he wrote on rec.sport.baseball, "I've been working on a pitching evaluation tool and thought I'd post it here to get some feedback. I call it 'Defensive Independent Pitching' and what it does is evaluate a pitcher base[d] strictly on the statistics his defense has no ability to affect. . ." . Until the publication of a more widely read article in 2001, however, on Baseball Prospectus
, most of the baseball research community believed that individual pitchers had an inherent ability to prevent hits on balls in play. McCracken reasoned that if this ability existed, it would be noticeable in a pitcher's 'Batting Average on Balls In Play' (BABIP). His research found the opposite to be true: that while a pitcher's ability to cause strikeouts or allow home runs remained somewhat constant from season to season, his ability to prevent hits of balls in play did not.
To better evaluate pitchers in light of his theory, McCracken developed "Defense-Independent ERA
" (dERA), the most well-known defense-independent pitching statistic. McCracken's formula for dERA is very complicated, with a number of steps. DIPS ERA is not as useful for knuckleballers
and other "trick" pitchers, a factor that McCracken mentioned a few days after his original announcement of his research findings in 1999, in a posting on the rec.sport.baseball.analysis Usenet site on November 23, 1999, when he wrote: "Also to [note] is that, anecdotally, I believe pitchers with trick deliveries (e.g. Knuckleballers) might post consistently lower $H numbers than other pitchers. I looked at Tim Wakefield's career and that seems to bear out slightly".
In later postings on the rec.sport.baseball site during 1999 and 2000 (prior to the publication of his widely-read article on BaseballProspectus.com in 2001), McCracken also discussed other pitcher characteristics that might influence BABIP. In 2002 McCracken created and published version 2.0 of dERA, which incorporates the ability of knuckleballers and other types of pitchers to affect the number of hits allowed on balls hit in the field of play (BHFP).
The controversy over DIPS was heightened when Tom Tippett at Diamond Mind
published his own findings in 2003. Tippett concluded that the differences between pitchers in preventing hits on balls in play were at least partially the result of the pitcher's skill. Tippett analyzed certain groups of pitchers that appear to be able to reduce the number of hits allowed on balls hit into the field of play (BHFP). Like McCracken, Tippett found that pitchers' BABIP was more volatile on an annual basis than the rates at which they gave up home runs or walks. It was this greater volatility that had led McCracken to conclude pitchers had "little or no control" over hits on balls in play. But Tippett also found large and significant differences between pitchers' career BABIP. In many cases, it was these differences that accounted for the pitchers' relative success.
Despite these later criticisms, the work by McCracken and others on DIPS is regarded by many in the sabermetric community as the most important piece of baseball research in many years.
DIPS ERA was added to ESPN.com's Sortable Stats in 2004.
in 1998 and can be calculated using simple math:
In that equation, "HR" is home runs, "BB" is walks, "HBP" is hit batters, "K" is strikeouts, and "IP" is innings pitched. That equation gives a number that is better at predicting a pitcher's ERA in the following year than the pitcher's actual ERA in the current year.
independently derived a similar formula, known as Fielding Independent Pitching, which is very close to the results of dERA and DICE.
In that equation, "HR" is home runs, "BB" is walks, "K" is strikeouts, and "IP" is innings pitched. That equation usually gives you a number that is nothing close to a normal ERA
, so the equation used is more often (but not always) this one:
That equation gives a number that is much closer to a potential pitcher's ERA.
The Hardball Times
, a popular baseball statistics website, uses a slightly different FIP equation, instead using 3*(BB+HBP-IBB) rather than simply 3*(BB) where "HBP" stands for batters hit by pitch and "IBB" stands for intentional base on balls.
Baseball
Baseball is a bat-and-ball sport played between two teams of nine players each. The aim is to score runs by hitting a thrown ball with a bat and touching a series of four bases arranged at the corners of a ninety-foot diamond...
, defense-independent pitching statistics (DIPS) measure a pitcher's effectiveness based only on plays that do not involve fielders: home run
Home run
In baseball, a home run is scored when the ball is hit in such a way that the batter is able to reach home safely in one play without any errors being committed by the defensive team in the process...
s allowed, strikeout
Strikeout
In baseball or softball, a strikeout or strike-out occurs when a batter receives three strikes during his time at bat. A strikeout is a statistic recorded for both pitchers and batters....
s, hit batters
Hit by pitch
In baseball, hit by pitch , or hit batsman , is a batter or his equipment being hit in some part of his body by a pitch from the pitcher.-Official rule:...
, walks
Base on balls
A base on balls is credited to a batter and against a pitcher in baseball statistics when a batter receives four pitches that the umpire calls balls. It is better known as a walk. The base on balls is defined in Section 2.00 of baseball's Official Rules, and further detail is given in 6.08...
, and, more recently, fly ball percentage, ground ball percentage, and (to much a lesser extent) line drive percentage. Those plays are under only the pitcher's control in the sense that fielders (not including the catcher) have no effect on their outcome.
Several sabermetric
Sabermetrics
Sabermetrics is the specialized analysis of baseball through objective, empirical evidence, specifically baseball statistics that measure in-game activity. The term is derived from the acronym SABR, which stands for the Society for American Baseball Research...
methods use only these "defense-independent" pitching statistics to evaluate a pitcher's ability. The logic behind using only these statistics is that once a ball is put in play, most often the pitcher has no effect on the resultant fielding of the ball. But defense-dependent statistics, such as the rate of hits allowed on balls put into play, are sometimes affected by the quality and/or arrangement of the defense behind the pitcher. For example, an outfielder may make an exceptionally strong diving catch to prevent a hit, or a base runner may beat a play to a base on a ball thrown from a fielder with sub par arm strength. Defense-independent statistics such as walks and strikeouts are determined almost solely by the pitcher's ability level.
While the creators of DICE, FIP and similar statistics all suggest they are "defense independent", others have pointed out that their formulas involve innings pitched(IP). Innings pitched is a statistical measure of how many outs were made while a pitcher was pitching. This includes those made by fielders who are typically involved in more than two thirds of the outs. These critics claim this makes pitchers' DICE or FIP highly dependent on the defensive play of their fielders.
In 1999, Voros McCracken
Voros McCracken
Robert "Vörös" McCracken is a prominent sabermetrician. Vörös is a nickname from his Hungarian heritage, meaning "red," specifically "blood red." He is most widely recognized for his pioneering work on Defense Independent Pitching Statistics .-DIPS published:McCracken first publicly disclosed his...
became the first to detail and publicize these effects to the baseball research community when he wrote on rec.sport.baseball, "I've been working on a pitching evaluation tool and thought I'd post it here to get some feedback. I call it 'Defensive Independent Pitching' and what it does is evaluate a pitcher base[d] strictly on the statistics his defense has no ability to affect. . ." . Until the publication of a more widely read article in 2001, however, on Baseball Prospectus
Baseball Prospectus
Baseball Prospectus 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 player and team performance projections on the site...
, most of the baseball research community believed that individual pitchers had an inherent ability to prevent hits on balls in play. McCracken reasoned that if this ability existed, it would be noticeable in a pitcher's 'Batting Average on Balls In Play' (BABIP). His research found the opposite to be true: that while a pitcher's ability to cause strikeouts or allow home runs remained somewhat constant from season to season, his ability to prevent hits of balls in play did not.
To better evaluate pitchers in light of his theory, McCracken developed "Defense-Independent ERA
Defense-Independent ERA
In baseball statistics,Defense-Independent ERA , created by Voros McCracken, projects what a pitcher's earned run average would have been, if not for the effects of defense and luck on the actual games in which he pitched.-Method:...
" (dERA), the most well-known defense-independent pitching statistic. McCracken's formula for dERA is very complicated, with a number of steps. DIPS ERA is not as useful for knuckleballers
Knuckleball
A knuckleball is a baseball pitch with an erratic, unpredictable motion. The pitch is thrown so as to minimize the spin of the ball in flight. This causes vortices over the stitched seams of the baseball during its trajectory, which in turn can cause the pitch to change direction—and even...
and other "trick" pitchers, a factor that McCracken mentioned a few days after his original announcement of his research findings in 1999, in a posting on the rec.sport.baseball.analysis Usenet site on November 23, 1999, when he wrote: "Also to [note] is that, anecdotally, I believe pitchers with trick deliveries (e.g. Knuckleballers) might post consistently lower $H numbers than other pitchers. I looked at Tim Wakefield's career and that seems to bear out slightly".
In later postings on the rec.sport.baseball site during 1999 and 2000 (prior to the publication of his widely-read article on BaseballProspectus.com in 2001), McCracken also discussed other pitcher characteristics that might influence BABIP. In 2002 McCracken created and published version 2.0 of dERA, which incorporates the ability of knuckleballers and other types of pitchers to affect the number of hits allowed on balls hit in the field of play (BHFP).
The controversy over DIPS was heightened when Tom Tippett at Diamond Mind
Diamond Mind
Diamond Mind Baseball is a computer baseball simulation game, created by Canadian baseball expert Tom Tippett, who released the first commercial version of the game in 1987. In 1992, he started doing baseball work full time....
published his own findings in 2003. Tippett concluded that the differences between pitchers in preventing hits on balls in play were at least partially the result of the pitcher's skill. Tippett analyzed certain groups of pitchers that appear to be able to reduce the number of hits allowed on balls hit into the field of play (BHFP). Like McCracken, Tippett found that pitchers' BABIP was more volatile on an annual basis than the rates at which they gave up home runs or walks. It was this greater volatility that had led McCracken to conclude pitchers had "little or no control" over hits on balls in play. But Tippett also found large and significant differences between pitchers' career BABIP. In many cases, it was these differences that accounted for the pitchers' relative success.
Despite these later criticisms, the work by McCracken and others on DIPS is regarded by many in the sabermetric community as the most important piece of baseball research in many years.
DIPS ERA was added to ESPN.com's Sortable Stats in 2004.
DICE
A simpler formula, known as Defense-Independent Component ERA (DICE), was created by Clay DresloughClay Dreslough
Clay Dreslough is the creator of the Baseball Mogul and Football Mogul computer sports games, and is the co-founder and President of Sports Mogul, Inc...
in 1998 and can be calculated using simple math:
In that equation, "HR" is home runs, "BB" is walks, "HBP" is hit batters, "K" is strikeouts, and "IP" is innings pitched. That equation gives a number that is better at predicting a pitcher's ERA in the following year than the pitcher's actual ERA in the current year.
FIP
Tom TangoTom Tango
Tom Tango and "TangoTiger" are aliases used online by a well-respected expert in baseball sabermetrics and ice hockey statistical analysis. He runs the Tango on Baseball sabermetrics website and is also a contributor to ESPN's baseball blog TMI .In 2006, Tango's book The Book: Playing the...
independently derived a similar formula, known as Fielding Independent Pitching, which is very close to the results of dERA and DICE.
In that equation, "HR" is home runs, "BB" is walks, "K" is strikeouts, and "IP" is innings pitched. That equation usually gives you a number that is nothing close to a normal ERA
Earned run average
In baseball statistics, earned run average is the mean of earned runs given up by a pitcher per nine innings pitched. It is determined by dividing the number of earned runs allowed by the number of innings pitched and multiplying by nine...
, so the equation used is more often (but not always) this one:
That equation gives a number that is much closer to a potential pitcher's ERA.
The Hardball Times
The Hardball Times
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 sabermetric personalities. The website features the slogan "Baseball. Insight...
, a popular baseball statistics website, uses a slightly different FIP equation, instead using 3*(BB+HBP-IBB) rather than simply 3*(BB) where "HBP" stands for batters hit by pitch and "IBB" stands for intentional base on balls.
xFIP
Dave Studeman of The Hardball Times derived Expected Fielding Independent Pitching (xFIP), a regressed version of FIP. Calculated like FIP, it replaces a pitcher's actual homerun total with an expected homerun total (xHR), where xHR is calculated using the league average of 10.6% HR/FB (home runs per fly ball). xFIP has the highest correlation with future ERA of all the pitching metricsSee also
- Baseball statisticsBaseball statisticsStatistics play an important role in summarizing baseball performance and evaluating players in the sport.Since the flow of a baseball game has natural breaks to it, and normally players act individually rather than performing in clusters, the sport lends itself to easy record-keeping and statistics...
- Defense-Independent ERADefense-Independent ERAIn baseball statistics,Defense-Independent ERA , created by Voros McCracken, projects what a pitcher's earned run average would have been, if not for the effects of defense and luck on the actual games in which he pitched.-Method:...
- Defense-Independent Component ERADefense-Independent Component ERAAbbreviated 'DICE', Defense-Independent Component ERA is a recent variation on Component ERA, one of an increasing number of baseball sabermetrics that fall under the umbrella of defense independent pitching statistics...
- SabermetricsSabermetricsSabermetrics is the specialized analysis of baseball through objective, empirical evidence, specifically baseball statistics that measure in-game activity. The term is derived from the acronym SABR, which stands for the Society for American Baseball Research...
- Voros McCrackenVoros McCrackenRobert "Vörös" McCracken is a prominent sabermetrician. Vörös is a nickname from his Hungarian heritage, meaning "red," specifically "blood red." He is most widely recognized for his pioneering work on Defense Independent Pitching Statistics .-DIPS published:McCracken first publicly disclosed his...