Understand Sabermetrics : On Base Plus Slugging (OPS)

OPS is a stat that combines two major functions in a baseball player's every day life, getting on base and hitting for power.  OPS is basically your on base percentage (OBP) added with your slugging percentage (SLG).

Like I said in the intro to this series no sabermetric stat is perfect and no sabermetric stat is a "tell all" stat. The biggest beef with OPS is how it weighs on base and slugging equally, which seems "unfair" for those who are not big power hitters. Slugging percentage numbers average between 75-100 points higher then on base numbers traditionally in baseball over a full season.  I do not believe in totally disqualifying stats because they are not "fair" because you have to know what stat to use for each situation and each player. You do not define Derek Jeter by his OPS because he is not a power hitter, he is a lead off hitter. A lead off hitter is defined mainly by their ability to get on base (OBP) and set the tone for the rest of the team. You want your best hitter, the #3 hitter traditionally, and your clean up hitter to have higher OPS numbers. 

OPS is set into 7 categories to determine how to rank a player. Here is the ranking via WIKI

Category	Classification	OPS Range
A	Great	.9000 and Higher
B	Moderate	.8333 to .8999
C	Above Average	.7667 to .8333
D	Average	.7000 to .7666
E	Below Average	.6334 to .6999
F	Terrible	.5667 to .6333
G	Atrocious	.5666 and Lower

The highest career OPS (entering 2011) is held by some guy named George Herman Ruth, with a staggering 1.1638 career OPS. He is followed closely by some names I have never heard of, guys like Ted Williams, Lou Gehrig, Barry Bonds, Jimmy Foxx, Albert Pujols, and Hank Greenberg to name a few.

Barry Bonds and Babe Ruth hold 8 out of the top 10 highest OPS seasons in baseball history, the other two are held by Ted Williams. The highest ever OPS in a season, by Barry Bonds, was an insane 1.4217 in the 2004 season.

Like I usually do, and like to do, let us use a Yankee to make this hit home a little bit. I wanted to use Mark Teixeira, but he does not walk a lot, and I wanted to use Alex Rodriguez but he barely played 100 games in 2011, so let us use the Yankees best hitter Robinson Cano. Robinson Cano, in 2011, had a OBP of .349 and had a SLG of .533 making his OPS a very respectable .882 putting him in the B category as a "moderate" OPS player. The fact that his OPS is so high with such a low OBP , compared to his batting average, and only  38 walks shows you just how good Robinson Cano is at making contact and hitting for power. 

There is an updated version of OPS, called OPS+, that is EXTREMELY complicated to understand and to use for a novice. I think it would be easier for you to read it HERE and try to understand it rather then my try to explain it.