Utente:Stefano PIERI/Sandbox/Statistiche Baseball

Le Statistiche rivestono un ruolo fondamentale nel riassumere il gioco del baseball e valutare le prestazioni dei giocatori in questo sport. Dato che lo scorrere della partita di baseball è interrotto per la sua stessa natura da intervalli tra le singole azioni, la registrazione e la tenuta di dati statistici sul gioco è enormemente semplificata. Ciò rende la comparazione tra le prestazioni dei giocatori in campo relativamente semplice, e questo da alle statistiche una importanza di gran lunga maggiore nel baseball che in altri sport. Nel baseball professionistico degli Stati Uniti, i dati statistici sono stati raccolti fin dalla nascita di ogni lega, nella seconda metà del XIX secolo. Inoltre una grande quantità di statistiche è disponibile anche per per associazioni diverse dalle Major League Baseball, come per esempio la National Association of Professional Base Ball Players o le Negro Leagues.

Sviluppo delle statistiche

La pratica di tenere registrazioni delle prestazioni dei giocatori fu iniziata nel XIX secolo da Henry Chadwick. Chadwick gettò le basi per gli antesignani delle moderne statistiche come la media battuta, i punti segnati, ed i Punti guadagnati sul lanciatore basandosi sulla sua esperienza, maturata nel cricket.

Tradizionalmente, statistiche come la media battuta per i battitori (il numero di battute valide diviso il numero di turni alla battuta) e la media punti guadagnati sul lanciatore (ERA) (il numero di punti concessi da un lanciatore ogni nove innings) sono state per oltre un secolo i capisaldi del mondo delle statistiche del baseball. Comunque, la recente nascita della sabermetrica ha portato alla ribalta un certo numero di nuove statistiche. Tali statistiche sono ritenute essere una migliore stima delle prestazioni dei giocatori e delle squadre anno dopo anno.

I dati statistici storici del baseball furono di difficile accesso fino al 1951 per il tifoso medio, quando il ricercatore Hy Turkin pubblicò The Complete Encyclopedia of Baseball. Nel 1969, la Macmillan Publishing dette alle stampe la sua prima Baseball Encyclopedia, utilizzando per la prima volta un computer per compilare le statistiche. Tale pubblicazione, che fu soprannominata "Big Mac", divenne lo standard di riferimento per il baseball fino al 1988, quando Total Baseball fu per la prima volta edito dalla Warner Books, sfruttando tecnologie ancora più sofisticate. Inoltre quest'opera codusse alla scoperta di diversi giocatori che non facevano parte del libro ufficiale dei record. Numerosi di questi "giocatori fantasma", come Lou Proctor, furono espunti dall'elenco dei dati ufficiali.

Utilizzo delle statistiche

General managers and baseball scouts study player statistics in order to make decisions on the abilities of players. Managers, catchers and pitchers study statistics of batters on opposing teams to figure out how best to pitch to them and position the players on the field. Managers and batters study opposing pitchers to figure out how best to hit against them. Managers often base their personnel decisions during the game on statistics, such as choosing who to put in the lineup, or which relief pitcher to bring in.

Throughout much of modern baseball, several core statistics have been traditionally used. Batting average, RBIs, and home runs are the most commonly referenced batting statistics. To this day, a player who leads the league in these three statistics is referred to as the "Triple Crown" winner. For pitchers, wins, ERA, and strikeouts are the most often cited traditional statistics. A pitcher that manages to lead the league in these statistics is also referred to as a "Triple Crown" winner.

Some sabermetric statistics have entered the mainstream baseball world. Among statistics that measure a batter's overall performance, On-base plus slugging (OPS) is one of the easiest to calculate. It adds the hitter's on base percentage (number of times reached base—by any means—divided by total plate appearances) to his slugging percentage (total bases divided by at bats). Some argue that the OPS formula is flawed and that more weight should be shifted towards OBP (on base percentage).

OPS is also useful when determining a pitcher's level of success. 'Opponent On-base Plus Slugging' (OOPS) is becoming a popular way to evaluating a pitcher's actual performance. When analyzing a pitcher's statistics, some useful categories to consider include K/9IP (strikeouts per nine innings), K/BB (strikeouts per walk), HR/9, WHIP (walks plus hits per inning pitched) and OOPS (opponent on-base plus slugging).

However, since 2001, more emphasis has been placed on Defense-Independent Pitching Statistics. These statistics, such as Defense-Independent ERA (dERA), attempt to evaluate a pitcher according to those events governed solely by the pitcher's performance, regardless of the strength of the defensive players behind him.

Also important are all of the above statistics in certain in-game situations. For example, a certain hitter's ability to hit left-handed pitchers might incline a manager to give him more chances to face lefties. Other hitters may have a history of success against a given pitcher (or vice versa), and the manager may use this information to engineer a favorable matchup.

The use of performance-enhancing anabolic steroids in Major League Baseball has affected the value of statistics, according to the Mitchell Report, released 13 December 2007, which concluded, in part

The illegal use of performance enhancing substances poses a serious threat to the integrity of the game. Widespread use by players of such substances unfairly disadvantages the honest athletes who refuse to use them and raises questions about the validity of baseball records.

Statistiche più usate

Most of these terms also apply to softball. Commonly used statistics with their abbreviations are explained here. The explanations below are for quick reference and do not fully or completely define the statistic; for the strict definition, see the corresponding article for each statistic.

Statistiche relative alla battuta

• 1B - Singolo - battuta valida mediante la quale il battitore raggiunge salvo la prima base.
• 2B - Doppio - battuta valida mediante la quale il battitore raggiunge salvo la seconda base.
• 3B - Triplo - battuta valida mediante la quale il battitore raggiunge salvo la terza base.
• AB - Turni alla battuta - apparizioni alla battuta, esclusi basi su balls, colpito dal lanciatore, sacrifici, interferenze e ostruzioni
• AB/HR At bats per home run - Turni alla battuta divisi per Fuoricampo
• BA - Media battuta (also abbreviated AVG) - hits divided by at bats
• BB - Basi su balls (also called a "walk") - times receiving four balls and advancing to first base
• BABIP Batting average on balls in play - frequency of which a batter reaches a base after putting the ball in the field of play. Also a pitching category.
• BB/K - Walk-to-strikeout ratio - number of base on balls divided by number of strikeouts
• XBH - Extra base hits - doubles plus triples plus home runs
• FC - Fielder's choice - times reaching base when a fielder chose to try for an out on another runner
• GO/AO - Ground ball fly ball ratio - number of ground ball outs divided by number of fly ball outs
• GDP or GIDP - Ground into double play - number of ground balls hit that became double plays
• GPA - Gross Production Average - 1.8 times on-base percentage plus slugging percentage, divided by four
• GS - Grand Slam - a home run with the bases loaded, resulting in four runs scoring, and four RBI credited to the batter.
• H - Hits - times reached base because of a batted, fair ball without error by the defense
• HBP - Hit by pitch - times touched by a pitch and awarded first base as a result
• HR - Home runs - hits on which the batter successfully touched all four bases, without the contribution of a fielding error.
• IBB - Intentional base on balls - times awarded first base on balls (see BB above) deliberately thrown by the pitcher. Also known as IW (intentional walk).
• K - Strike out - number of times that strike three is taken or swung at and missed, or bunted foul
• LOB - Left on base - number of runners not out nor scored at the end of an inning.
• OBP - On base percentage - times reached base (H + BB + HBP) divided by at bats plus walks plus hit by pitch plus sacrifice flies (AB + BB + HBP + SF).
• OPS - On-base plus slugging - on-base percentage plus slugging average
• PA - Plate appearance - number of completed batting appearances
• RC - Runs created - statistic that attempts to measure how many runs a player has contributed to his team
• RP - Runs produced - statistic that attempts to measure how many runs a player has contributed
• RBI - Run batted in - number of runners who scored due to a batters' action, except when batter grounded into double play or reached on an error
• RISP - Runner In Scoring Position - the batter's batting average with runners in scoring position
• SF - Sacrifice fly - number of fly ball outs to the outfield which allow a runner already on base to score
• SH - Sacrifice hit - number of sacrifice bunts which allows another runner to advance on the basepaths or score
• SLG - Slugging average - total bases divided by at-bats
• TA - Total average - total bases, plus walks, plus hit by pitch, plus steals, minus caught stealing divided by at bats, minus hits, plus caught stealing, plus grounded into double play
• TB - Total bases - one for each single, two for each double, three for each triple, and four for each home run
• TOB - Times on base - times reaching base as a result of hits, walks, and hit-by-pitches
• BsR - Base Runs - Another run estimator, like Runs Created; a favorite of writer Tom Tango
• XR - Extrapolated Runs - A linear run estimator developed by Jim Furtado

Statistiche relative alla corsa sulle basi

• CS - Caught stealing - times tagged out while attempting to steal a base
• SB - Stolen base - number of bases advanced other than on batted balls, walks, or hits by pitch
  • DI - Defensive Indifference - if the catcher does not attempt to throw out a runner (usually because the run would be insignificant), the runner is not awarded a steal
• R - Runs scored - times reached home base legally and safely

Statistiche relative al lancio

• BB - Base on balls (also called a "walk") - times pitching four balls, allowing the batter-runner to advance to first base
• BB/9 - Base on balls times nine divided by innings pitched (Bases on balls per 9 innings pitched)
• BF - Total batters faced - opponent's total plate appearances
• BK - Balk - number of times pitcher commits an illegal pitching action or other illegal action while in contact with the pitching rubber, thus allowing baserunners to advance
• BS - Blown save - number of times entering the game in a save situation, and being charged the run (earned or not) which eliminates his team's lead
• CERA - Component ERA - an estimate of a pitcher's ERA based upon the individual components of his statistical line (K, H, 2B, 3B, HR, BB, HBP)
• CG - Complete game - number of games where player was the only pitcher for his team
• DICE - Defense-Independent Component ERA - an estimate of a pitcher's ERA based upon the defense-independent components of his statistical line (K, HR, BB, HBP)
• ER - Earned run - number of runs that did not occur as a result of errors or passed balls
• ERA - Earned run average - total number of earned runs (see "ER" above), multiplied by 9, divided by innings pitched
• ERA+ - Adjusted ERA+ - earned run average adjusted for the ballpark and the league average
• G - Games (aka 'appearances') - number of times a pitcher pitches in a season
• GF - Games finished - number of games pitched where player was the final pitcher for his team
• G/F - Ground ball fly ball ratio - ground balls allowed divided by fly balls allowed
• GS - Starts - number of games pitched where player was the first pitcher for his team
• H/9 - Hits per nine innings - hits allowed times nine divided by innings pitched (also known as H/9IP - Hits allowed per 9 innings pitched)
• H - Hits Allowed - total hits allowed
• HB - Hit batsman - times hit a batter with pitch, allowing runner to advance to first base
• HLD (or H) - Hold - number of games entered in a save situation, recorded at least one out, did not surrender the lead, and did not complete the game
• HR - Home runs allowed - total home runs allowed
• IBB - Intentional base on balls allowed
• IP - Innings pitched - number of outs recorded while pitching divided by three
• IP/GS - Average number of innings pitched per game
• IR - Inherited runners - number of runners on base when the pitcher enters the game
• IRA - Inherited runs allowed - number of inherited runners allowed to score
• K - Strikeout - number of batters who received strike three
• K/9 - Strikeouts per nine innings - strikeouts times nine divided by innings pitched (Strikeouts per 9 innings pitched)
• K/BB - Strikeout-to-walk ratio - number of strikeouts divided by number of base on balls
• L - Loss - number of games where pitcher was pitching while the opposing team took the lead, never lost the lead, and went on to win
• OBA - Opponents batting average - hits allowed divided by at-bats faced
• PIT - Pitches thrown (Pitch count)
• QS - Quality start - a game in which a starting pitcher completes at least six innings and permits no more than three runs
• RA - Run average - number of runs allowed times nine divided by innings pitched
• R.R.A - Relief Run Average - A function of how many inherited base runners a relief pitcher allowed to score.
• SHO - Shutout - number of complete games pitched with no runs allowed
• SO - Strikeout Also may be notated as 'K'.
• SV - Save - number of games where the pitcher enters a game led by the pitcher's team, finishes the game without surrendering the lead, is not the winning pitcher, and either (a) the lead was three runs or less when the pitcher entered the game; (b) the potential tying run was on base, at bat, or on deck; or (c) the pitcher pitched three or more innings
• W - Win - number of games where pitcher was pitching while his team took the lead and went on to win (also related: winning percentage)
• WHIP - Walks and hits per inning pitched - average number of walks and hits allowed by the pitcher per inning
• WP - Wild pitches - charged when a pitch is too high, low, or wide of home plate for the catcher to field, thereby allowing one or more runners to advance or score

Statistiche relative alla difesa

• A - Assists - number of outs recorded on a play where a fielder touched the ball, except if such touching is the putout

• DP - Double plays - one for each double play during which the fielder recorded a putout or an assist.
• E - Errors - number of times a fielder fails to make a play he should have made with common effort, and the offense benefits as a result
• FP - Fielding percentage - total plays (chances minus errors) divided by the number of total chances
• INN - Innings - number of innings that a player is at one certain position
• PB - Passed ball - charged to the catcher when the ball is dropped and one or more runners advance
• PO - Putout - number of times the fielder tags, forces, or appeals a runner and he is called out as a result
• RF - Range factor - ([putouts + assists]*9)/innings played. Used to determine the amount of field that the player can cover
• TC - Total chances - assists plus putouts plus errors
• TP - Triple play - one for each triple play during which the fielder recorded a putout or an assist

Statistiche Generali

• G - Games played - number of games where the player played, in whole or in part
• Pythagorean expectation - estimates a team's expected winning percentage based on runs scored and runs allowed.

MLB statistical standards

It is difficult to determine quantitatively what is considered to be a "good" value in a certain statistical category, and qualitative assessments may lead to arguments. It is interesting to look at recent results for some typical statistics and let the reader draw their own conclusions. Using full-season statistics available at the Official Site of Major League Baseball for the 2000 through 2006 seasons, the following tables show top ranges in various statistics, in alphabetical order. For each statistic, two values are given:

• Top5 - the top five players bettered this value in all of the reported seasons
• Best - this is the best of all of the players for all of the reported seasons

Arguably, a statistic that falls within the range shown might be considered as good.

Batting Statistics Statistic Top5 Best BA .321 .372 HR 43 73 RBI 124 150 SLG .595 .863

Pitching Statistics Statistic Top5 Best CG 4 9 ERA 3.19 1.74 G 77 94 GS 34 36 IP 231⅔ 266 K 207 372 SHO 2 5 SV 38 55 W 18 24

See also

• Triple Crown in Major League Baseball
• MLB Most Valuable Player Award winners
• Cy Young Award winners
• MLB Rookie of the Year Award winners
• Gold Glove Award winners
• Retrosheet
• List of pitches
• Official Baseball Rules (OBR)
• Evolution of baseball player evaluation

Note e riferimenti

Riferimenti

• Alan Schwarz, The Numbers Game: Baseball’s Lifelong Fascination with Statistics (New York: St. Martin's, 2005)(ISBN 0-312-32223-2).
• Curveball (ISBN 0-387-98816-5) - A book on new statistics for Baseball.*
• The Official Site of Major League baseball - Baseball Basics: Abbreviations

Voci correlate

• Ball
• Strike
• Strike zone