On-base plus slugging


On-base plus slugging 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 represented. An OPS of.900 or higher in Major League Baseball puts the player in the upper echelon of hitters. Typically, the league leader in OPS will score near, and sometimes above, the 1.000 mark.

Equation

The basic equation is
where OBP is on-base percentage and SLG is slugging average. These averages are defined.
- the numerator "H + BB +HBP" effectively means "number of trips to first base at least"
- the denominator "AB + BB + SF +HBP" effectively means "total plate appearances"
- this is because though a batter makes a trip to the plate he is not given an "AB" when he walks or when he hits the ball into play and is called out but the action allows a run to score as in the SF scenario. As a result, the 4 counts are needed to calculate a batter's total trips to the plate.
and
where:
In one equation, OPS can be represented as:

History

On-base plus slugging was first popularized in 1984 by John Thorn and Pete Palmer's book, The Hidden Game of Baseball. The New York Times then began carrying the leaders in this statistic in its weekly "By the Numbers" box, a feature that continued for four years. Baseball journalist Peter Gammons used and evangelized the statistic, and other writers and broadcasters picked it up. The popularity of OPS gradually spread, and by 2004 it began appearing on Topps baseball cards.
OPS was formerly sometimes known as production. For instance, production was included in early versions of Thorn's Total Baseball encyclopedia, and in the Strat-O-Matic computer baseball game. This term has fallen out of use.
OPS gained popularity because team average OPS correlates well with team runs scored. However, it is not mathematically legitimate to use this correlation to assume that individual OPS correlates as well with individual runs created, nor is it legitimate to assume that individual OBP correlates well with individual runs created.

An OPS scale

, in his essay titled "The 96 Families of Hitters" uses seven different categories for classification by OPS:
CategoryClassificationOPS range
AGreat.9000 and higher
BVery good.8334 to.8999
CAbove average.7667 to.8333
DAverage.7000 to.7666
EBelow average.6334 to.6999
FPoor.5667 to.6333
GVery poor.5666 and lower

This effectively transforms OPS into a seven-point ordinal scale. Substituting quality labels such as excellent, very good, good, average, fair, poor and very poor for the A–G categories creates a subjective reference for OPS values.

Leaders

The top ten Major League Baseball players in lifetime OPS, with at least 3,000 plate appearances through the end of the 2019 season were:
  1. Babe Ruth, 1.1636
  2. Ted Williams, 1.1155
  3. Lou Gehrig, 1.0798
  4. Barry Bonds, 1.0512
  5. Jimmie Foxx, 1.0376
  6. Hank Greenberg, 1.0169
  7. Rogers Hornsby, 1.0103
  8. Mike Trout, 0.9999
  9. Manny Ramirez, 0.9960
  10. Mark McGwire, 0.9823
The top four were all left-handed batters. Jimmie Foxx has the highest career OPS for a right-handed batter.
The top ten single-season performances in MLB are :
  1. Barry Bonds, 1.4217
  2. Barry Bonds, 1.3807
  3. Babe Ruth, 1.3791
  4. Barry Bonds, 1.3785
  5. Babe Ruth, 1.3586
  6. Babe Ruth, 1.3089
  7. Ted Williams, 1.2875
  8. Barry Bonds, 1.2778
  9. Babe Ruth, 1.2582
  10. Ted Williams, 1.2566
The highest single-season mark for a right-handed hitter was 1.2449 by Rogers Hornsby in, 13th on the all-time list. Since 1935, the highest single-season OPS for a right-hander is 1.2224 by Mark McGwire in, which was 16th all-time.

Adjusted OPS (OPS+)

OPS+, adjusted OPS, is a closely related statistic. OPS+ is OPS adjusted for the park and the league in which the player played, but not for fielding position. An OPS+ of 100 is defined to be the league average. An OPS+ of 150 or more is excellent and 125 very good, while an OPS+ of 75 or below is poor.
The basic equation for OPS+ is
where *lgOBP is the park adjusted OBP of the league and *lgSLG is the park adjusted SLG of the league.
A common misconception is that OPS+ closely matches the ratio of a player's OPS to that of their league. In fact, due to the additive nature of the two components in OPS+, a player with an OBP and SLG both 50% better than league average in those metrics will have an OPS+ of 200 while still having an OPS that is only 50% better than the average OPS of the league. It would be a better approximation to say that a player with an OPS+ of 150 produces 50% more runs, in a given set of plate appearances, as a player with an OPS+ of 100.

Leaders in OPS+

Through the end of the 2019 season, the career top twenty leaders in OPS+ were:
  1. Babe Ruth, 206
  2. Ted Williams, 190
  3. Barry Bonds, 182
  4. Lou Gehrig, 179
  5. Mike Trout, 176
  6. Rogers Hornsby, 175
  7. Mickey Mantle, 172
  8. Dan Brouthers, 171
  9. Joe Jackson, 170
  10. Ty Cobb, 168
  11. Pete Browning, 163
  12. Jimmie Foxx, 163
  13. Mark McGwire, 163
  14. Dave Orr, 162
  15. Stan Musial, 159
  16. Hank Greenberg, 158
  17. Johnny Mize, 158
  18. Tris Speaker, 157
  19. Dick Allen, 156
  20. Willie Mays, 156
  21. Frank Thomas 156
The only purely right-handed batters to appear on this list are Hornsby, Foxx, Trout, McGwire, Allen, and Thomas. Mantle is the only switch-hitter in the group.
The highest single-season performances were:
  1. Barry Bonds, 268
  2. Barry Bonds, 263
  3. Barry Bonds, 259
  4. Fred Dunlap, 258 *
  5. Babe Ruth, 256
  6. Babe Ruth, 239
  7. Babe Ruth, 239
  8. Ted Williams, 235
  9. Ted Williams, 233
  10. Ross Barnes, 231 **
  11. Barry Bonds, 231
* - Fred Dunlap's historic 1884 season came in the Union Association, which some baseball experts consider not to be a true major league.
** - Ross Barnes may have been aided by a rule that made a bunt fair if it first rolled in fair territory. He did not play nearly so well when this rule was removed, although injuries may have been mostly to blame, as his fielding statistics similarly declined.
If Dunlap's and Barnes' seasons were to be eliminated from the list, two other Ruth seasons would be on the list. This would also eliminate the only right-handed batter in the list, Barnes.

Criticism

Despite its simple calculation, OPS is a controversial measurement. OPS weighs on-base percentage and slugging percentage equally. However, on-base percentage correlates better with scoring runs. Statistics such as wOBA build on this distinction using linear weights. Additionally, the components of OPS are not typically equal. As a point of reference, the OPS for all of Major League Baseball in 2019 was.758.