Strasburg Breaks NERD
If, over the past month or so, you’ve kept your eyes on the prize that is FanGraphs, you might’ve very well come across my humble attempts at devising a point system to preemptively adjudge the appeal of any given pitching matchup to the baseball nerd aesthetic.
To recap briefly, the resulting number — called NERD — is computed by taking the sum of the z-scores (i.e. standard deviations from the mean) for the following categories (weighted to best fit the tastes of the baseball nerd): xFIP, age, fastball velocity, strike percentage (of total pitches thrown), and swinging-strike percentage. To that total is added a pitcher’s “luck” (that is, ERA-xFIP, capped at 2), and a constant (around 4) to have everything come out approximately on a scale of 0-10. Additionally, because it seems a bit ridiculous to compute a toy stat to the decimal level, I’ve rounded the results.
The final thing I’ve done after all that is to round any scores above 10 down to that number (i.e. 10) and any NERDs below 0 up to that number (i.e. 0). Nor has this really caused any sort of problem. With about 170 pitchers in the sample, only about 10 or 12 have ever gone above or below the 0-10 range — and even then, never by more than 2 points.
Until Stephen Strasburg came along, that is.
Were we still living in a pre-Strasburgian world, these would be your current NERD leaders (rNERD = rounded NERD, aNERD = actual NERD):
What you’ll notice about that group is that they have the good sense not to dominate the rest of the league to such a degree as to to render NERD useless. Francisco Liriano’s un-rounded 11.25 is the highest mark I’ve seen to date, but at least it’s on a human scale.
The same goes for our laggards, whom you see here (in a table that has been, for a reason that only my computer knows, reproduced more poorly than the other two in this post):
Again, despite dipping into the negatives, neither Snell nor Monasterios nor the rest of their incompetent friends reach depths that problematize NERD’s competence unduly.
But cast your eyes all the way to the tippy-top of the NERD leaderboards and you’re faced with this:
Apparently, Stephen Strasburg has no sympathy for this modest experiment, as his NERD score almost doubles that of the next-best pitcher in the majors.
Of course, it’s no trouble to see why Strasburg rates so highly: he’s got an xFIP of 1.54, an average fastball velocity of 97.5 mph, the highest swinging-strike rate in the league, and he’s only 21 years old.
Strasburg’s excellence asks an interesting question of NERD and, by extension, the question we might ask of ourselves when choosing which game to watch on the nights that he’s pitching: Is Strasburg, all by himself, enough of a spectacle to make a game worth watching? Because, really, with the exception of Snell or Monasterios (neither of whom, let it be known, are currently in a major league starting rotation), any pitcher, when combined with Strasburg, will give the game an average NERD score of 10 amongst its starting pitchers.
Put concretely: Is Strasburg vs. Brad Lincoln more interesting than Roy Halladay vs. Josh Johnson? The latter match-up has happened at least a couple of times now, and one of those resulted in a perfect game for Halladay. That’s pretty great shakes. On the other hand, Strasburg really does represent everything of interest to the baseball nerd — to the baseball fan, in general, really.
The ancillary question, of course, is whether it’s smart/necessary to round NERD scores outside of the 0-10 range back into that range. In most cases, it’s not an issue: again, only 10 or 12 players — somewhere in the vicinity of 5-10 percent — ask that question. But NERD is designed to represent the taste of the sabermetrically inclined fan, and so the question is a fine one to ask.
The best answer, for now, is probably to see if Strasburg can keep it up. So long as he does, maybe there just has to be a Strasburg Bonus. In any case, it’s not the worst problem to have.
