There is no Pirate more divisive than Nyjer Morgan right now. Some people see his speed and enthusiasm for the game and can't think of a more exciting player. Others see players like him as relics of a bygone era where Omar Moreno could bat leadoff with a .310 OBP because he was fast. What's interesting is that there doesn't seem to be any common ground between the two sides. Nyjer apologists seem to think that Nyjer haters can't possibly see any value in a player like Morgan, while Nyjer haters seem to think that Nyjer apologists are blind to the fact that he might not be a good player.
I'd guess that most readers think I fall into the "Nyjer hater" class, but I don't think this is entirely fair. I think there's room for a player like Morgan on a Major League team, provided that he can be productive. The problem, at least in my eyes, is that I think that Morgan has to be better than people realize to be productive. Without much power and with much of his OBP tied up in walks, Morgan probably has to hit .320 or .330 to be a productive leadoff man, whereas Nate McLouth can be a productive 3-hitter with .270 average so long as he shows some pop and takes his walks.
While trying to think of a way to address this gap, I came up with a new stat that I'm going to call NewlY adJusted Efficiency Rating, or NYJER. We'll start with a simple tweak to a familar formula; adjust on-base percentage by subtracting caught stealings from times on base and adjust slugging percentage by adding stolen bases to total bases. Then add them together like OPS. It's more or less a hacked version of raw equivalent average and it's certainly flawed, but I think it's a good start.
It's not quite perfect, though, because it seems like an OPS analogue and it's not because it strongly overvalues stolen bases. This is because caught stealings count against plate appearances, while steals count towards at-bats. For example, if a batter is hitting 30-for-90 with 10 walks and 45 total bases (.333/.400/.500), and has stolen 10 bases in 20 chances, his NYJER adjusts to .300/.611 = .911. Thus, he's gained on his OPS for stealing bases at a very poor rate.
I'd much rather this stat be used mostly for comparison purposes, especially with leadoff hitters. To avoid confusion, let's just set a baseline by determining what would be a good number for a leadoff hitter. For the answer to that question, let's look at the two guys I find Morgan to be compared to the most, Juan Pierre and Willy Taveras. Pierre is a great example of a Nyjer Morgan style player; he was a good hitter with the Marlins when his batting average was high, but since his average has started to drop, he's been a black hole of outs in lineups all across the country. In both 2003 and 2004 with the Marlins, his equivalent average was above .270, which is pretty good (league average is always .260). I think that's about the level Morgan has to reach to be a good enough player to consider keeping him in the lineup. Anything under that, and he should be headed to the bench.
In 2003, Pierre hit .305/.361/.373, stealing 65 bases and getting caught 20 times. His OPS is .734, but accounting for his steals adjusts that to .319/.470 = .789. In 2004, he hit .326/.374/.407 with 45 steals in 69 attempts. That adjusts to .323/.473 = .796. Using those numbers as a guide, we'll set the NYJER baseline for a productive season at .790 and divide any number we get by that. A NYJER of 1.000 is a good number for a leadoff hitter, while one of below 1.000 isn't.
NYJER = [(times on base - caught stealing)/plate appearances + (total bases + stolen bases)/at-bats]/.790
To test that baseline, let's look at Willy Taveras last year. He sucked something awful for Colorado, hitting .251/.308/.296, but he was awesome on the basepaths, stealing 68 bases in 75 tries. Does NYJER skew his line too heavily? By my adjustment, he's at .276/.438 = .714, which gives him a NYJER of .903. It's not perfect (if I wanted perfect, I'd just use equivalent average), but it's easy to calculate and most importantly, it's easy to understand, so while you won't see it on BP, THT, or FanGraphs anytime soon, I think it works for our purposes.
Right now, Morgan's hitting .323/.371/.415 with six steals in seven attempts. That's .343/.508 = .851, which is a NYJER of 1.077, which is pretty good. But the point is that there's not a ton of leeway. If we just drop 20 points of batting average (not an absurd proposition by anyone's standards, I don't think) and put him at .303/.351/.395 and throw in one more caught stealing, he drops right down around the 1.000 mark. So if Nyjer Morgan's going to be a good player this year, he's got to continue right along at the rate he's playing at right now and he doesn't have a ton of room for error.