1,000+ Great Games/1_1000 Games.iso/GAMES_1/APBASTAT.ZIP/DISK2.ZIP/GLOSSARY.DOC

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    C Copyright 1987, 1988 Miller Associates.  All rights reserved.

 GLOSSARY

 Below are definitions of terms used by StatMaster with which you may not
  be familiar.  In certain cases we have identified the person who introduced
  the concept as it is used today.  In a few cases the definition given
  differs slightly from the definition used by its creator to account for
  statistics that are not kept by BASEBALL.  Where possible, we give ranges
  and average values of each performance measure for teams or players in
  the big leagues.


 Defensive Efficiency Record -- A measure of what percentage of balls
  put into play against a team were converted to outs.  A Bill James
  statistic.

 DER is calculated by dividing Plays Made (PM) by the sum of Plays Made
  and Plays Not Made:

     DER = PM/(PM+OH-OHR+(.71)E)

 ("O" in front of a stat means "opposition"; .71E is an estimate of the
  number of team errors which allowed a batter to get on base.)

 Plays Made--or the number of balls put into play which were turned into
  outs--is calculated by taking the average of two estimates.

     Est. #1    PM = PO-OSO-OCS-A(of)-.93TG

 Explanation: a ball put into play is an out if it's a putout unless it's
  a strikeout, or a caught stealing, or a runner put out on the bases, or
  if more than one out was made on the play (.93 is an approximation of
  the average number of double plays, plus two times triple plays made by
  each major-league team in a game.)

     Est. #2    PM = OAB+OS-OH-OSO-(.71)E

 Explanation: a ball put into play is an out if it's an opposition at bat
  or a sacrifice bunt/fly unless it's a hit, or a strikeout, or a batter who
  was allowed to reach base on an error.

 Bigs: an average DER for major-league teams is about .695, which is to
  say that about 3 balls in 10 that were put into play were hits or led
  to errors, and about 7 in 10 were converted to outs.


 Earned Runs Prevented -- The "Linear Weight" measure of a pitcher's
  performance.  (See also Runs Contributed.)  A measure of how many runs
  a pitcher prevented compared to an average pitcher in the league who
  pitched the same number of innings.  (Earned runs prevented may be
  translated into losses prevented by dividing by runs required per win
  for that league.)  Remember that ERP measures the extent to which
  a pitcher is better than average, not his total contribution.
  Runs-prevented leaders are published weekly in the New York Times
  (currently on Wednesdays) and in other newspapers.  A Pete Palmer statistic.

 Earned runs prevented = (ERA - league ERA)/(IP/9)

 Bigs: best ERP = 30 to 60 runs per 162-game season (30-40 starts).
  Average ERP = 0.


 Fielding Percentage -- The percentage of balls handled that were fielded
  cleanly.  PCT = (PO+A)/(PO+A+E)

 Bigs: average performance differs by position.  A typical season might
  be P--.958, C--.986, 1B--.992, 2B--.981, 3B--.955, SS--.963, and OF--.981.
  Modern major-league teams generally field from .970 to .985 overall;
  leagues average .979.  Note: in BASEBALL 1.0, there were too many outfield
  errors.  BASEBALL 1.1 corrected that.

 The differences between team fielding percentages is about 1.5% and between
  individual players (non-pitchers), no more than 3-4% at each position.
  These are indicators--along with URP below--that fielding is not a major
  factor in run prevention/creation, not when compared to pitching and
  batting.  Sabermetric analysis, as practiced by Messrs. Palmer, Thorn,
  and others, concludes that fielding is about 6% of baseball, pitching 44%,
  and batting 50%.  Every player, manager, and fan, of course, has an
  opinion about the relative importance of various aspects of the game.
  We suspect that, happily, disagreements about methods of baseball analysis
  will persist.


 Offensive Support -- The average number of runs that a team scored in
  games started by an individual pitcher.  A measure of how much better or
  worse a pitcher is than his won-lost record indicates.  Pitchers with less
  than average support may have been better than their record indicates, and
  pitchers with more than average support may have been worse.

 Bigs: most support = 5.5 to 6.5 runs per game; least support = 2.9 to 3.5
  runs per game.  Average support is just the average runs scored by each
  team in a game: in 1986, 4.18 r/g without the DH, 4.61 r/g with the DH,
  and 4.41 r/g overall.


 On-base Percentage -- A measure of how often a batter reaches base due
  to his effort as a percentage of his opportunities to reach.

 OBP = (H+BB+HP)/(AB+BB+HP)

 Bigs: typically, league OBP = .330, team OBP = .300 to .340, player
  OBP = .250 to .450.


 Opposition Batting Average -- The batting average of the opponents of
  a specific team or pitcher against that team or pitcher.  OBA = OH/OAB

 For individual pitchers, an approximation is used: OBA = OH/((IP*3)+OH).
  The actual OBA would be 10 to 14 points higher after adjusting for outs
  made on the base paths by players whose plate appearance was not an at bat.

 Bigs: league OBA = league batting average (recently has been approximately
  .255 without DH, .265 with DH), team OBA = same as team batting averages
  (typically .230 to .280), pitcher OBA = .200 to .300.


 Opposition Stolen Base Average -- The average number of opposition stolen
  bases per game in games started by each catcher or pitcher.  A measure of
  their effectiveness at stopping the running game.  A Bill James statistic.

 For catchers: OSBA = (OSB/GS at catcher).
 For pitchers: OSBA = (OSB/GS).

 Bigs: for catchers and pitchers, about .5 to 1.3 stolen bases allowed per
  game (less is better).


 Opposition Stolen Base Percentage -- See Stolen Base Percentage.


 Power Average -- A player's slugging average minus his batting average.
  Bill James calls this Isolated Power.  Branch Rickey championed this stat.
  Power average is a measure of a player's ability to hit for power
  considered apart from his ability to hit singles.  PA = Slg - BA

 Bigs: in 1986, league PA = .127 without DH; .146 with DH.  Team PA = .091
  to .147 without DH; .130 to .167 with DH.  For an individual, PA under .080
  means he can be considered a singles hitter; PA over .200 is very good power.


 Quality Starts -- The number of starts in which a pitcher went at least
  six innings and yielded no more than three earned runs.

 Bigs: quality starts in over 60% of games started is considered good.


 Range Factor -- The number of chances accepted per game.  A Bill James
  statistic.  Range = (PO+A)/DG

 Bigs: performance differs by position.  Typical season range factors might
  be 2B--4.50 to 6.00, 3B--2.00 to 3.30, SS--4.00 to 5.30, R/LF--1.50 to 2.50,
  and CF--2.30 to 3.20.  BASEBALL 1.0 skewed slightly the outfielder range
  factors.  BASEBALL 1.1 corrected that.  See the note under Fielding
  Percentage.


 Runs Contributed -- An estimate of the number of runs contributed to
  a team's offense by each player above the number contributed by an average
  player in the league.

 Like runs created, runs contributed is an attempt to measure the overall
  offensive contribution of a player in terms of the only thing that
  ultimately counts, number of runs.  If you divide runs contributed by the
  runs required per win (approximately 10, see "Runs Required Per Win"),
  you have the wins contributed by this player's offensive performance above
  the league average.  A Pete Palmer statistic.

 Pete actually calls runs contributed "Batting Runs" to distinguish it from
  Defensive Runs, Stolen Base Runs, and Pitching Runs, all "Linear Weights,"
  and all measures of contributions to the team stated in terms of runs.
  (For Pitching Runs, see "Earned Runs Prevented.")  In the formula below,
  we use the historical average .25 for the league factor (it can vary from
  approximately .24 to .26 from one year to the next).  This means that the
  sum of runs contributed for all players is not precisely zero, as it would
  be if the league factor were adjusted to overall league performance.
  In comparing players from a single season, their relative performance is
  not changed by using this approximation.

 Runs contributed = (.46)S+(.80)D+(1.02)T+(1.40)HR+(.33)(BB+HP)
                   +(.30)SB-(.60)CS-(.25)(AB-H)

 Bigs: an average player would contribute approximately zero (0) runs above
  average.  An average outfielder might contribute 20 runs in 400 plate
  appearances above the average player in the league.  On the other hand,
  a good shortstop might be expected to contribute no runs above the average
  player in the league.  Clearly, outfielders are expected to be better
  offensively than shortstops.

 Players having great seasons contribute 40 to 70 runs; very poor seasons
  are in the range -40 to -20.  Only players who play a lot can have a very
  high or low season total, since the absolute number is dependent on number
  of games played.


 Runs Created -- An estimate of the number of runs that a player would
  produce based on his offensive statistics. Runs created is an attempt to
  measure total offensive contribution in terms of runs (see also Runs
  Contributed).  Divided by the runs required per win (in professional
  baseball, approximately 10), runs created becomes the total wins created
  by this player's offensive performance. A Bill James statistic.

 RC = ((H+BB+HBP-CS)*(TB+.26(BB+HBP)+.52(SB+SAC)))/(AB+BB+HBP+SAC)

 If a player is used primarily as a pinchrunner with few plate appearances
  (CS > (H+BB+HBP)) then a different formula is used to try and capture the
  players contribution. The (((H+BB)*TB)/(AB+BB)) part of the formula is the
  basic runs created formula.

 RC = ((.52*SB)-CS) + (((H+BB)*TB)/(AB+BB))

 Bigs: typically ranges from 0 to 120 in a 162-game season, more than 40 for
  the best starting players.  Only players who play a lot can have a very
  high season total, since the number is dependent on total stats.  For a
  team, runs created is a projected estimate of the runs the team should have
  scored given its number of hits (by type), walks, stolen bases, and times
  caught stealing.  Comparing team runs created to actual runs scored gives
  an indication of other factors at work, factors that effect the efficiency
  of a team's offense.  For instance, high efficiency--consistently scoring
  more runs than projected--could be explained by good clutch hitting, good
  baserunning, good managing, or good luck.  The more consistent the two
  figures, the less luck is probably involved.


 Runs Required Per Win -- A measure of the number of runs that are
  required to win one more game.  This is not the number of runs that are
  needed to win any single game, but rather the number that when added to
  total team runs, would project to one more win for the team.  Historically
  for professional baseball it has been approximately 10, varying from year
  to year between 9 and 11.

 In APBA leagues in which the talents of players are not representative of
  baseball as a whole--many small leagues will have very good pitching or
  hitting--the runs required per win may vary more widely.  It is important
  to take this into account when you are evaluating the runs created and
  runs contributed of an individual player, especially when you are
  comparing performances from one year to another.  In your league, suppose
  it takes 9 runs one year to create a win, and because of great hitting in
  the league, it takes 12 runs the next year.  A player who contributes 36
  runs in the first year will have contributed 4 wins more than the average
  player, while this same performance will only be 3 wins above average the
  next year.  See Pete Palmer.

 Runs required per win = sq rt (league runs/(league innings pitched/2))*10


 Slugging Percentage -- A measure of a hitter's power and batting average
  combined.  Slg = TB/AB

 Bigs: in general league Slg = .380 without DH, .408 with DH (1986 stats,
  up from .376 and .401 in 1983).  Team Slg = .325 to .450, player Slg = .250
  to .500.


 Stolen Base Percentage -- The success rate of stealing bases.
 Sabermetricians appear to be in wide agreement that if an individual's
 or a team's base stealing percentage is less than .670 (67% or 2 out of 3
 successful), then the running game is costing the team more runs than it
 is creating.  SB Pct = SB/(SB+CS)

 Bigs: in recent years the annual stealing success rate has been between .630
 and .710 for professional baseball divisions, between .550 and .770 for
 teams, and varies widely for individuals.  A league-leading percentage
 among frequent base stealers is generally around .800 (80% successful).
 For a team, 1.4 attempts/game is a lot; .6 attempts/game is very few.

 In 1986 professional baseball players stole successfully at a rate of .672,
  so their base stealing contributed approximately nothing to overall run
  production.  A Project Scoresheet study by Kevin Hoare provides strong
  evidence that base stealing attempts lower the batting average of the
  player at bat during the attempt, possibly by as much as 50 batting
  average points and 100 slugging average points.  Stealing attempts also
  increase on-base average, possibly by 40 points or more, but this does
  not appear to outweigh the negative impact on batting.  More research is
  called for in this area.  In BASEBALL, stealing attempts reduce the batting
  average of the player at bat.


 Total Average -- A ratio of the bases a player accumulates for his team
  and the outs he costs his team.  Total average is a Thomas Boswell statistic
  included in a delightful book, How Life Imitates the World Series.

 Total average = (TB+BB+SB+HP-CS)/(AB-H+CS)

 BASEBALL does not count double plays, so players who hit into many DP's
  will appear better in total average than they would if the complete TA
  formula were used.  Using the above formula, division total averages for
  1986 were .682 and .667 without the DH and .729 and .694 with the DH.
  If a player has a TA over 1.000, that's very good.


 Total Bases -- The total number of bases achieved by the batter on hits.
  As with most stats, to make total bases indicative, it must be put in the
  context in which it occurred.  For instance, total bases divided by at bats
  is slugging percentage, which is one indicator of power.

 TB = S+(2*D)+(3*T)+(4*HR)

 Bigs: in 1986 teams without the DH averaged 12.9 total bases/game; with
  the DH, 13.9 total bases/game.


 Total Plate Appearances -- The number of times a player appeared as
  a batter.  TPA is sometimes used as the context for evaluating another
  counter stat or as a condition for qualifying for the leader boards (see
  Offensive Leader Boards).  TPA = AB+BB+HB+S

 Bigs: teams averaged 38.2 plate appearances/game in 1986.


 Unearned Run Percentage -- Unearned runs allowed by a team as a
  percentage of total runs allowed.  URP = (R-ER)/R

 Bigs: overall, for professional baseball in 1986, URP = .106, that is,
  about 10% of the runs were unearned.  Teams' URP varied from .077 to .129.
  See Fielding Percentage discussion above.



 BIBLIOGRAPHY

 "The APBA Journal."  Howard Ahlskog, Editor and Publisher.
 Address: 65 Norwood, Greenfield, MA 01301. Monthly. $15.00 (1987)

 Boswell, Thomas.  How Life Imitates the World Series.
 New York: Penguin Books, 1983 (hardback, Doubleday, 1982).  ppb $5.95

 James, Bill. The Baseball Abstract.  New York: Ballantine Books,
 Annually 1982 to 1988.  $8.95 each

 Neft, David S. and Richard M. Cohen.  The Baseball Sports Encylopedia,
 1988 Edition.  New York: St. Martin's Press.  $15.95

 Project Scoresheet.  The Great American Baseball Stat Book.
 New York: Ballantine Books, 1987.  $12.95

 Siwoff, Seymour, and Steve Hirdt and Peter Hirdt.
 The Elias Baseball Analyst.  New York: Collier Books, 1987, 1988.  $12.95

 Thorn, John and Pete Palmer, with David Reuther.
 The Hidden Game of Baseball.  New York: Doubleday & Company, 1985.  $10.95