Yes it's true. I’ve had trouble with the On-base Plus Slugging (OPS) statistic for a few years, but it’s not what you’re thinking. I don’t think a player's batting average or RBI tell the whole story of offense, I’m not attached to any stat (traditional or otherwise), and I don’t think a scout’s horse sense is always better than good analysis. These are the common assumptions about me of people who feel they’ve found the Holy Grail in OPS.
My problem isn’t that I’m stuck in the old ways, it’s that I like reality. I understand that stats are maps, or descriptions if you like, of reality (not reality itself), and I like my maps to reflect reality in some tangible way. Let me explain, or rather, ask a question. When a player has an OPS of .800, what is that .800 of?
My problem with OPS is that it’s not .800 of anything, it doesn’t refer directly to anything in the game. If someone has an OPS of .800, it doesn’t mean that 8 out of 10 times anything happens, it’s just a scale. As baseball fans we have gotten used to the stat as it has been forced down our throats, and so we understand that league average is somewhere in the mid to high .700s, and that over .800 is pretty good, over .900 is very good, and over 1.000 is MVP voting. But because in taking into account both OBP and SLG we have looked at times where the player goes up to be pitched to (plate appearances and at bats) twice, we can’t relate the numbers to anything in the game. It’s overly complex for no reason.
The standard reasoning that is given to me for why we should use OPS, is that team OPS predicts team runs better than any other common statistic. That means that you would want your players to have high OPSs, because you are then likely to score more runs. I checked this out for the year so far and here are the runs scored for the top ten teams in each simple stat category:
AVG: 3871
OBP: 3806.5 (tie for 10th)
SLG: 3901
OPS: 3914
So it seems that so far this year, the OPS advocates have been right. But is there no simpler way? I thought I’d find out. The stat I came up with is Bases per Plate Appearance (BPA), and it is equal to total bases + walks + hit by pitches + stolen bases all divided by plate appearance. That’s (TB+BB+HBP+SB)/PA. What that would give you is how many bases a player advances on their own per time up to bat, which actually reflects something. If someone has a BPA of .485, you know that they get a little less than half a base per PA, on average. Makes sense right?
Now to apply the formula to team runs. Lo and behold for the year so far the top ten teams in BPA have scored 3921 runs, which is more than the top ten teams in OPS. PM me if you want all the numbers.
Seeing this I was elated, thinking that I might have found a simple stat that relates to reality easily and works as well as OPS. I checked on last years results to see if they showed the same thing.
The top ten OPS teams scored 8634 runs in 2004, and the top ten BPA also scored 8634 runs. They were in fact the same teams, and both were better than all of the other simple stats. The same results were found in 2003. The top ten teams in OPS scored 8591 runs, as did the top ten BPA teams (who were again the same teams).
So why not use the one that lets you easily relate the numbers to the game? Instead of saying Derek Lee has an OPS of 1.177 and guessing what that means, we could say he averages .777 bases per plate apearance. Brian Roberts has a BPA of .704, that's a pretty tough out I'd say.
I know I'm not going to start a revolution here, and that there are probably way more effective and complex stats for the GMs out there, but I needed to say my piece because I think OPS is stupid. There I said it. Why would you count times up to bat twice? It just doesn’t make sense.
Also, since BPA is doing better than OPS so far this season at predicting runs scored, I thought this might be a nice thing to write for all of those fans out there who think OPS is the be all end all of simple stats, and have gotten as attached to it as the old guard was to AVG. Let us always remember that the map is not the territory, and no number shows everything. One day someone might come up with something better and simpler than OPS, and we’ll all have to change again. If I had more clout, that day might be today.