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SESSION IV: Error replacement proposal, initial briefing and discussion

Proposal by Professor Rich Carzez, 28-year veteran scorekeeper of the Carolina League

SANDY ALDERSON: OK, let’s get started. If you didn’t get a sandwich and something to drink over there on the side—thanks, Tom—yes, if you didn’t grab refreshments be sure to get something. OK, we have professor, or doctor? Professor Carzez. He has a proposal for a statistic to replace the error, which obviously has its faults and difficulties and, ah, yes, so we’re going to hear this proposal and have some time afterward to ask some questions. Take it away, the projector and remote there should be working OK, yes?

RICH CARZEZ: Yes, thank you, Mr. Alderson. And thank you all for allowing me to present this, it’s an honor. I applaud you all for your open-mindedness in considering a replacement for the error.

This would, undeniably, be a shock to the system. The error has its permanent place on line scores. It’s involved in determining the most basic of statistics, embedded in the fabric of the game. Yet it’s increasingly apparent that the error, as currently defined, fails to accomplish its mission, fails to reflect reality in our contemporary understanding of the play on the field.

You may have seen several strong articles that explained, using Statcast data, why the error felt particularly ill-equipped to assess a Jackie Bradley Jr. play in August. In short, Bradley exceeded the abilities of most any other outfielder simply by getting close enough to get a glove on the ball, but was punished—in terms of the error—for not hauling it in. The hitter, meanwhile, was docked a few bases that, again, he would “earn” against most other fielders.

When issues like this are highlighted, many gravitate toward solutions that add factors into the process, such as Statcast’s catch probability metric. And while that technology is certainly promising and interesting, I think those ideas might be a bit too narrowly tailored. See—and I know I’m not breaking any news to the folks in this room—most serious evaluations of baseball don’t make much, or any, use of errors to study defensive performance. So, attempting to combine errors with measures of defensive ability, in my view, only muddies the waters and distracts from a) figuring out who is good at defense, and b) describing how a given set of events unfolded in a game and led to the result. Those two goals, I’m going to posit, don’t necessarily align.

To best determine what outcomes were the result of one player simply winning a battle—getting around on a high, 97 mph fastball—instead of a player making a mistake, we need fewer stipulations, restrictions and inputs, not more. Indeed, my stance is that the error’s impertinence in measuring defensive prowess affords us the opportunity to find an altogether better way to tell the story of how this batter got to second base, or how that man on first base ended up scoring. We have a chance to accurately identify and catalog results born of all mistakes made in the motion of a play—not only on defense, but on the base paths.

The statistic I’m proposing to capture these moments is called the “derp.”

JOHN SMOLTZ: Sorry, the … ?

CARZEZ: The derp, D-E-R-P. I’ll explain the name a bit later, but let me get a basic working definition out there.

A derp is any physical or mental miscue that clearly alters the action of a play, and costs one’s team a base or bases. Derps can be assessed to defenders, runners, or pitchers dealing with the running game. All derps are labeled by their total immediate cost in terms of position on the bases.

A couple examples: There’s a man on first base, and the hitter grounds a hard single up the middle. If the center fielder boots it and allows the lead runner to advance to third base, that’s a one-base derp. If the batter also advances to second base, it becomes a two-base derp. It’s credited to the hitter’s stat line as a single either way.

Now, let’s talk about baserunning. Here’s a simple one to start. A batter hits a line drive into right field that rolls to the wall, but he trips rounding first base, like Francisco Lindor on his first career hit.


The physical miscue makes a single out of what was clearly something more. That is counted as a double and a one-base derp.


JERRY DIPOTO: My apologies. Excuse me for a moment.

ALDERSON: So how can you award a double on that example? How can you be sure he would have made it to second base?

CARZEZ: Well, it’s a judgment call. It’s not dissimilar to how scorers award errors right now when a liner bounces off a third baseman’s glove or a dribbler ends up near the mound. Is it a hit? Is it an error? Those close plays make for a lot of tricky decisions, and scorers do the best they can. Right now, though, they are restricted from telling the story we know to be true in many cases. In others, they won’t be sure. Take this hit by Elvis Andrus.

He trips rounding first base, but everyone watching—most noticeably the broadcast team—knows it made no difference. It didn’t alter the play. That’s a single. His stumble doesn’t meet our standard—it didn’t clearly alter the play. I don’t think these sorts of calls would be very common. Nonetheless, I humbly submit that the derp gives the box score and the play-by-play a better chance at detailing what actually happened. It is descriptive at heart, even though it gives scorers more room to act on the judgments they are no doubt making anyway.

SMOLTZ: Would scorers all of a sudden have to be using exit velocity and launch angles and things to decide what is what?


SMOLTZ: Because it’s just getting too complicated. A hit is a hit, you know? It doesn’t make a difference if it’s a bloop or a liner, they all go in the newspaper the same.

CARZEZ: Right, no. There wouldn’t be any significant change in the use of technology. The scorers will simply be making their judgments from watching the play. Even today they often have to assess whether balls hit to infielders were struck sufficiently hard that they should be counted as hits. And sometimes, they are hamstrung by outmoded and frankly illogical tenets of the error rule. This is why Drew Butera—no offense to him—has an inside-the-park homer when it just really isn’t possible for him to earn one.


That should count as a hit for Butera, certainly. However, the fact that Jake Cave failed to touch the ball on his dive hardly excuses his attempt. Under my proposal, a scorer would rule that a single. Then, they would evaluate the position of the baserunners. The man on second base looked primed to score, but the one on first base likely wouldn’t have gone to third base if the ball were fielded adequately. So, single and a five-base derp against Cave (two for the runner on first base, three for Butera) would be the scoring decision. Butera would get an RBI, and so on.

OK, one last point: How derps would be recorded and relayed. In a single-game context, the column at the end of the line score could be used to present a simple counting stat: Bases Derped. The number in that column would sometimes be higher than you’d usually see in the error column, but the point would be quite similar, offering a glimpse into the cleanliness of each team’s game.

There are plenty of details on specific situations and implications on statistics in the packet you’ve been given. For example, throwing to the wrong base could be a derp in cases of a blatant mistake. Anyway, I’ll mention that there isn’t a fully defined plan for using derps to study a full season or career, as I believe the public baseball brain trust will come to fill that void better than I could.

I have spoken to some statistical folks about devising a DERP Score (Derps Exceeding Replacement Player) that creates an average, so to speak, by using each player’s game-action opportunities as a denominator. It would perhaps also regress for opponents doing the running or fielding, and take a number of other factors into account, but that isn’t anything to worry about with the proposal. This is very much an effort focused on creating a more intuitive way for scorers, and thus, history, to document each game.

Thank you.


ALDERSON: Questions for professor Carzez?

ROBERTO ALOMAR: I really have to know where “derp” came from.

CARZEZ: Oh, it’s something my daughter said back in high school that comes from the internet, and I’ve found it feels quite fitting to say after a mistake on the field.

MARK SHAPIRO: Thank you for the proposal, professor Carzez. Do you believe derps, as you call them, should factor into a player’s value in relation to arbitration or awards?

CARZEZ: Good question. I do think some of these factors are already accounted for by baserunning and fielding metrics that go into WAR. So the derp would simply be a way of explaining games better via box scores. However, if there is a player making a lot of miscues, or a player making none, then sure, I imagine those tendencies would be illuminated for the community to quantify in a value sense.

SMOLTZ: Isn’t this a little too much? Do people really need a new number to learn? I mean, I feel like we’re bombarding them with things and making the game feel like a chore or a class or something.

CARZEZ: With all due respect, no one will be forced to know how derps are applied. I’d say a large portion of the people who watch each broadcast today don’t think too hard about whether that two-run play in the seventh inning was a hit or an error. They just know it happened. Those folks will continue on their merry way, if you let them, untroubled by the change.

For another set of fans, though—possibly a larger set—baseball’s completist obsession with keeping records, with seeking understanding, is a foundational aspect of their relationship to the sport. It’s not just about the memory of Butera rounding the bases or Lindor laughing at himself. It’s about the long, slow drama of finding out exactly how good they are, or even how weird that one memory was. Anything we can do to make our coded, written history align more with the way the games are experienced, in my book, is a positive.

ALDERSON: Well, OK. Thanks. We’ll take this under consideration.

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Matthew Gold
So, how would the Jackie Bradley play be scored in a DERP world? It's not clear that the change from error to DERP helps there.
Daniel R. Epstein
Everything about this is awesome.
Jim Maher
I think this is far more arbitrary than errors, though that is seriously flawed too. When Kipnis let a popup last night drop 2 feet from him, it may not have been an error since he doesn't touch the ball, but if the hitter scores it shouldn't be charged to the pitcher. But if a guy makes a terrific effort on a dive that is virtually uncatchable and can't quite catch it and the runner gets an extra base, I would hate to penalize the fielder for the heroic effort. And if he does catch it and saves the hitter's base and the base runners' bases, does he get a negative derp? Exceeding normal fielding achievement should generate negative derps.
Aaron Barbara
The problem is we refuse to assess errors when they should apply. If we use the standard definition of ordinary effort then it should be irrelevant whether or not you touched the baseball. If a pop up falls that should have been caught I would assess an error because the outcome is different than what it should have been. If an outfielder plays a obvious single into a triple it is clearly an error. Any outcome where the offense benefits more than it should have must be the result of an error. Why should a pitcher be punished by an outcome that should not have been? Errors don't need to be removed they simply need to be applied correctly.
Edward Martin
From time to time over the decades, I've heard broadcasters wish for a ruling of "team error" for muffed rundowns, popups or fly balls that land between fielders who call each other off, etc., when it wasn't possible to assing an error to a particular player. The derp seems like a good vehicle for this; "bases derped" doesn't have to be solely an individual statistic. Pitchers should love the derp (at salary negotiation time, anyway): the concept of "unearned" run will expand to include runs that wouldn't have scored without derped bases. One thing's for sure: in a derp world, official scorers will have to be trained--and paid--a lot better, because they'll be working harder.
Edward Martin
Aaron Barbara
assing the play gets you an error
Aaron Barbara
speaking of assing things up Why can't comments be edited?

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