Batting Glossary - Baseball-Reference.com

 Year Ag Tm  Lg  PA  Outs  RC  RC/G   AIR    BA *lgBA   OBP *lgOBP  SLG *lgSLG  OPS *lgOPS*OPS+  OWP *BtRns BtWin SB% 
+--------------+----+----+----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+----+-----+-----+-----+----+
 2003 20 NYM NL  292  199   42   5.6   108| .307  .267| .334  .339| .434  .429| .768  .768| 100  .592  -0.9  -0.1  81%
 2004 21 NYM NL  229  171   24   3.8   110| .255  .268| .271  .340| .373  .435| .644  .775|  65  .405 -12.0  -1.2  90%
 2005 22 NYM NL  733  536   84   4.2   107| .273  .267| .300  .338| .386  .426| .686  .763|  80  .471 -24.3  -2.5  80%
 2006 23 NYM NL  703  478  116   6.5   108| .300  .266| .354  .336| .487  .432| .841  .768| 118  .639  14.5   1.4  79%
+--------------+----+----+----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+----+-----+-----+-----+----+
 4 Seasons      1957 1384  266   5.1   108| .285  .267| .321  .338| .427  .430| .748  .767|  95  .550 -22.7  -2.4  80%

* indicates the value is park adjusted

Pitch Data Summary (Show or Hide)

 Year  PA  Pit Pit/PA  Str  Bll Strk%|  StL%  StS%  StF%  StI%| BlI%| SOc SOs  SOc%| Swng% SwgA% Cntc%  1st%|  30%  30c 30s  20%  20c 20s  31%  31c 31s| PAu  PiU  StU
+----+---+----+------+----+----+-----+------+-----+-----+-----+-----+----+---+-----+------+-----+-----+-----+------+---+---+-----+---+---+-----+---+---+----+----+----+
 2003 292  999   3.42  669  330   67%|   27%   12%   24%   36%|   0%|   7  29    19|   73%   49%   83%   27%|    5%  15   1   14%  40   8    5%  14   9|   0    0    0 
 2004 229  808   3.53  559  249   69%|   29%   12%   25%   35%|   0%|   8  23    26|   71%   49%   84%   24%|    1%   3   0   10%  24   3    4%  10   6|   0    0    0 
 2005 733 2653   3.62 1814  839   68%|   30%    9%   27%   35%|   0%|  16  62    21|   70%   48%   87%   27%|    3%  22   0   11%  81  13    7%  54  22|   0    0    0 
 2006 703 2536   3.61 1687  849   67%|   28%   11%   28%   34%|   3%|  14  67    17|   72%   48%   85%   28%|    4%  27   0   14%  98  24    9%  61  27|   0    0    0 
+----+---+----+------+----+----+-----+------+-----+-----+-----+-----+----+---+-----+------+-----+-----+-----+------+---+---+-----+---+---+-----+---+---+----+----+----+
  Tot            3.57             68%|   29%   10%   26%   34%|   1%|           20%|   71%   48%   85%   27%|    3%      1%   12%     20%    7%     46%|               
  Avg            3.75             63%|   27%   14%   27%   31%|   2%|           26%|   73%   46%   80%   28%|    5%      6%   15%     39%    9%     55%|

I included all of the player's seasons assuming they actually had a plate appearance, and when they appeared for several teams, I also included both league and season totals (if those are different). For those the team is TOT and the league is either ZZ if they appeared in multiple leagues, or the league if just one league.

Here is a run down of the columns.

Year - Year in which the season occurred
Ag - Player age on July 1st of that year.
Tm - Team they played for (see Team ID's)
Lg - League they played in (AL- American League, NL- National League)
G - Games played
AB - At Bats
R - Runs Scored
H - Hits
2B - Doubles
3B - Triples
HR - Home Runs
RBI - Runs Batted in
SB - Stolen Bases
CS - Caught Stealing (were counted in the AL after 1919 and after 1950 in the NL)
BB - Base on Balls or Walks
SO - Strikeouts or whiffs or K's (are available hit and miss between 1882 and 1912, but are available for all other seasons)
BA - Batting Average H/AB
OBP - On-Base Percentage (H+BB+HBP)/(AB+BB+SF+HBP) (SF and HBP are assumed zero if unavailable, see SF and HBP below)
SLG - Slugging Percentage TB/AB (see TB below)
TB - Total Bases (Singles + 2*2B + 3*3B + 4*HR)
SH - Sacrifice Hits or Bunts (were first counted in 1895 and includes Sac Flies until 1953)
SF - Sacrifice Flies (were first counted in 1954, prior to that they were included in Sac Hits)
IBB - Intentional Base on Balls (were first counted in 1955)
HBP - Hit by Pitch (are available for every season after 1887)
GDP or GIDP - Grounded into Double Plays
End Notations (SS, MVP, AS, ROY) - Tacked onto the end of the batting lines are notations if the player won the Silver Slugger (SS), was an All-star (AS), or received votes for the MVP or Rookie of the Year (ROY).
OPS - It doesn't appear here, but OPS is On-Base Percentage + Slugging Percentage. It is a pretty good estimate of offensive ability.
Adjusted OPS+ - It doesn't appear on the player pages yet, but OPS+ is OPS (see above) normalized for both the park and the league the player played in. See below for a full description.
hmR/G and rdR/G - average runs per game scored by this team in home and road games.

NOTE: When a stat is unavailable its season entry should be blank, rather than zero. This may not always be the case, but it is what I've tried to do. This is not true of the career batting lines.

The career totals and the number of seasons is then next. In some cases this is staggered on two lines for presentation purposes.

Special Batting

This area contains some additional statistics along with some advanced analytic or sabermetric stats. These stats attempt to give an in depth look at what the player's statistics mean within the context of the league and position they played in. These stats are subject to change and improvement as we flesh out this area.

Year - Year in which the season occurred
Ag - Player age on July 1st of that year.
Tm - Team they played for (see Team ID's)
Lg - League they played in (AL- American League, NL- National League)
PA - Approximate Plate Appearances - AB + BB + HBP + SF + SH
Outs - (AB - H + CS + GIDP + SH + SF)
RC - Runs Created - A runs estimator created by Bill James. A runs estimator attempts to quantify the entire contribution of a player's statistics to a team's total runs scored. It typically involves some positive value for things like hits, walks, steals, home runs, etc. and negative values for outs, caught stealing and GIDP. There are 24 different versions of RC depending on the stats you have. In general, I am using the tech version which incorporates baserunning, HBP and other offensive events. When those aren't available I use the SB version, and when those aren't available, I use the basic version, (H + BB) * (TB)/ (AB + BB)
RC/G - Runs Created per Game - Typically the average game has around 27 outs, but this can vary by the size of the homefield advantage and the number of extra-inning games. We use the seasonal average outs/game.
OWP - Offensive Winning Percentage - This is an estimate of the winning percentage an average defense with nine of this player batting would have. As was pointed out to me, the standard formula using the league's runs scored doesn't work well for 19th century players because so many of their runs were unearned and they took lots of extra bases and the like. I'm of two minds on how to handle this. One approach is to tweak the runs created formula. Another would be to use the league runs created rather than league runs. I have done the latter, so now we use the sum of the league's runs created to calculate offensive winning percentage.
btRuns Adjusted Batting Runs - This is the linear weights method pioneered by Pete Palmer. It is a bit more accurate than Runs Created and also handles differing offensive environments more easily. It is adjusted to the park and league the player played in. It is also relative to league average, so negative values mean they were below average for the league. In my calculations, I consider league average without pitchers included. See the ESPN Baseball Encyclopedia for a full description.
btWins - Batting Wins - Another Pete Palmer tool, this measures the number of wins a player added relative to the league average hitter. See the ESPN Baseball Encyclopedia for a full description.
AIR - I call this AIR because it is how pumped up a player's stats are by the park and leagues they played in. I looked at the median league OBP and SLG from 1901 to the present and it historically is around .335 for league OBP and .400 for league slugging. Not quite, but those are the closest round numbers. Next I take, 100*((park-adjusted Lg OBP/ .335) + (park-adjusted Lg SLG /.400) - 1) to come up with the player's AIR factor. 100 means they hit in historically average settings. Over 100 means higher offensive environment than usual. Under 100 means lower offensive environment than usual.
BA and lgBA - Batting average and the league's batting (pitchers removed) average with the same home field.
OBP and lgOBP - On-base percentage and the league's on-base percentage (pitchers removed) with the same home field.
SLG and lgSLG - Slugging percentage and the league's Slugging percentage (pitchers removed) with the same home field.
OPS and lgOPS - On-base percentage + Slugging and the league's on-base + slugging percentage (pitchers removed) with the same home field. This is a very good rough guide to a player's ability to get on base and also drive runners in. High OPS means lots of runs for the team.
OPS+ - Adjusted OPS, see below. Essentially OPS normalized to the league. Think of it as a rate above the league average expressed as a percentage.
SB% - Stolen Base Percentage SB/(SB+CS)

Adjusted OPS+

This value is calculated differently from the Total Baseball PRO+ statistic. I chose OPS+ to make this difference more clear. PRO+ as best I can tell is

PRO+ = 100 * ( OBP/lgOBP + SLG/lgSLG - 1)/BPF

Where lgOBP and lgSLG are the slugging and on-base percentage of a league-average player, and BPF is the batting park factor. This takes into account the difference in runs scored in a team's home and road games, so it doesn't depend on how good an offense or defense a team has.

My method is slightly more complicated, but I think it is more correct. The BPF is set up for runs and the way it is implemented in PRO+ applies it to something other than runs.

Compute the runs created for the league with pitchers removed (basic form) RC = (H + BB + HBP)*(TB)/(AB + BB + HBP + SF)
Adjust this by the park factor RC' = RC*BPF
Assume that if hits increase in a park, that BB, HBP, TB increase at the some proportion.
Assume that Outs = AB - H (more or less) do not change at all as outs are finite.
Compute the number of H, BB, HBP, TB needed to produce RC', involves the quadratic formula. The idea for this came from the Willie Davis player comment in the Bill James New Historical Baseball Abstract. I think some others, including Clay Davenport have done some similar things.
Using these adjusted values compute what the league average player would have hit lgOBP*, lgSLG* in a park.
Take OPS+ = 100 * (OBP/lgOBP* + SLG/lgSLG* - 1)
Note, in my database, I don't store lgSLG, but store lgTB and similarly for lgOBP and lg(Times on Base), this makes calculation of career OPS+ much easier.

Career "High"

Below that is the career high for the player in each category. It is not their best season, but the best (highest/sometimes lowest) from all the categories. You can quickly see what Barry Bonds's career highs in strikeouts were along with walks, home runs, etc. I required the qualifying number of plate appearances in a season to be considered for the career best BA, SLG and OBP entries to be 1.55/team game. If I didn't do this you would end up with some players having a 1 hit in 2 at bats cup of coffee as their career best batting average.

162 Game Average

This is an attempt to condense each batter's career into a single season's worth of stats. With batters this is easy. Just take their career games played and divide by 162 and then divide their career totals by that factor.

Team Pages

Pythagorean W-L: Developed by Bill James, this attempts to measure the number of wins and losses a team is expected to have given the number of runs they score and the number of runs they allow. The Pythagorean winning percentage, which you then use to get the W-L record, is given by:

                Runs Scored * Runs Scored
-----------------------------------------------------------
(Runs Scored * Runs Scored) + (Runs Allowed * Runs Allowed)

The rest of the team pages work essentially the same as the player pages, except for the POS column. This column is based on Total Baseball's shorthand for positions played. It works as follows. The positions are C (catcher), 1 (first base), 2 (second base), 3 (third base), O (outfield), S (shortstop), P (pitcher), D (designated hitter), H and R (pinch hitter and runner). If there is a * before a position means the player appeared in at least 2/3rd's of the teams games at that position. Any numbers to the left of the '/' signify at least ten games played at that position and to the right of the '/' signify less than ten games. If no '/' appears the player played at least ten games at each position listed.

We have also attempted to highlight the players who played the most games at each position. Note that there are a number of errors in these listings, though I would say they are 90-95% accurate.

For further questions or comments, send us a note.

Stats updated through August 18, 2008.

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