WAR Against OPS

by Lawrence S. Katz

Steven Katz ed.

Not Wins Against Replacement. That’s a subject for another day. I’m talking about another kind of war - one I’ll start here against OPS, the combination of On Base Percentage (OBP) plus Slugging Average (SLG). This sum is exalted for its ability to reduce a player’s skills at the plate to a single number. The idea, of course, is to measure the ability of a player to both get on base – On Base Percentage - and hit for power - Slugging Average. According to the conventional wisdom (try Bill James himself), by combining statistics with established and unassailable track records for measuring two important hitting skills, a reliable measure of a player’s offensive value emerges.  According to this thinking, for every player, an OPS of .800 or higher is very good and an OPS of .900 is great.

With W.A.R. still perceived by many people as too complicated and convoluted, OPS has overtaken Batting Average as the single most important index of all-around offensive prowess. Given inside-baseball’s near-universal acceptance of the stat, my war was probably lost before it starts. But my memory of the failure of the Game Winning RBI stat keeps hope alive.  

Let’s examine the flaws of this superstat:

1.  OPS mixes apples and oranges.  Some things belong together: Peanut butter and jelly; hydrogen and oxygen; hot dog and mustard. Some things do not. Yes, OBP and SLG are easy to understand, easy to calculate, and time-tested measures of a hitter’s ability. But that doesn’t mean they should be clumped together. On Base Percentage measures the ability to reach base, Slugging Average measures power, and the two have little to do with each other.

What do Tony Gwynn and Reggie Jackson have in common? Their OPSes were almost identical - Jackson at .846 and Gwynn one point higher at .847. They’re both in the Baseball Hall of Fame for their achievements at the plate. But they were polar opposites in terms of the actual skills they brought to their respective clubs. Gwynn got on base a lot. Reggie Jackson hit a lot of home runs. By most measures – balls put in play, runners moved over, run production, whatever - the two players had little in common. OPS might be the last stat a general manager would look at in trying to figure whether a player was the right fit for his club.

 2.  OPS is not a balanced offensive measure. It is not “transparent,” if you'll excuse the overused term.  Since Slugging Average tends to be 50-150 points higher than On Base Percentage, OPS will always be top-heavy on the slugging side. (Consider the difference in the two denominators; the maximum On Base Percentage is 1.000 while the maximum Slugging Average is 4.000.) All skills being equal, the scale is tipped heavily in favor of long-ball hitters against the guys who get on base more. With Slugging Average carrying the day, OPS is not a balanced measure of overall offensive ability. Thus, OPS may be the only stat where deconstruction becomes an essential tool of analysis. Only when baseball fans break down a .767 OPS into a .310 OBP and a .457 SLG, or into a .380 OBP and a .387 SLG, can they gauge a player’s real value.   

3.  OPS is actually a throwback statistic. Statistics are the lifeblood of the game. The range of ways to gauge performance has been expanding since the first diamond was laid out. The recent explosion of new ways to measure success and failure is breathtaking. A Nineteenth Century record book would fit neatly into the palm of your hand. In the mid-Twentieth Century, the career records of several players could fit on a single page. Now, the statistical life of even the most obscure player consumes several pages. Like most everything else in the real world, overall achievement is judged by many standards over an expanse of time. The worth of everything (stats included) lies in context. Is OPS an irony? Or is OPS a return to a simpler time? Are we actually wearying from the abundance of new measurements of performance?

4.  Simply put, it just isn't useful. So let's replace it with something that is. The number doesn't mean anything. The number seems benign, but it doesn't actually represent anything tangible. Sure, it's easy to calculate, but that's really the only thing going for it. And compared to the mathematics involved in modern advanced statistics, modifying the OPS equation into something that represents meaningful, concrete information about a player's performance should be a breeze. In place of OPS, I propose a Total Bases Average (TBA) that would present a number signifying how many bases a batter earned per plate appearance. Total bases, including base on balls and hit by pitches, divided by plate appearances. That's simple enough. And best of all, it actually tells you something clear and meaningful about a player's offensive production.

I urge the baseball establishment to get rid of this irrelevant statistic.  If you're itching to see how OBP and SLG look together, you don’t need a separate column on a stat sheet; simply add the two numbers on your own. I'm just not sure why you would.