Fangraphs has an interesting article on the declining value of pitch framing for catchers. It is also a good object lesson on adaptive learning by officials.
Pitch framing for the non-statistical geeks is how a catcher receives a ball. A catcher that is deliberate, calm and stable will be able to get pitches that are objectively outside of the strike zone called strikes. A stable catcher who does not move much is a little visual cue that the ball went where it was intended which increases the probability that the pitch will be called a strike.Catchers who are herky-jerky will see a number of balls that are in the objective strike zone called as balls. This has been a hack on umpires as they are reading the pitcher, the ball and the catcher.
Good pitch framers can contribute the equivalent of an extra win or two per season. Bad pitch framing catchers cost their teams an extra win. It is a skill that can be worth $10 million dollars a year at the major league level.
Some teams have been aggressively pursuing pitch framing catchers as a market inefficiency (the Pirates are one of them) as they’ll give up offense for subtle defense.
However the umpires may be striking back:
Humans can learn; humans can be trained. One interesting observation during the PITCHf/x era is that, over time, those human umpires have collectively started to call an increasingly consistent zone. PITCHf/x provided feedback, and umpires could get better as a result. Now, I can’t help but wonder if we’re seeing the beginning of the end for pitch-framing. Catchers are always going to catch a little differently, but I wonder if there are fewer available rewards….
And the correlations used to be pretty consistent, until a step back two years ago and a bigger step back one year ago. It’s not shown here, but the top 10 framing catchers from 2014 kept just 57% of their value in 2015, which is another low for the PITCHf/x era…..
The rest is in the hands of the umpires, and at some point, umpires were going to catch wind of what was taking place. And then they could have a response, because umpires don’t want to be manipulated, not intentionally and not for a team’s direct gain…..
All sports where there is human judgement involved will have subtle areas of exploitation. In soccer, there is a cottage industry of forwards who use hand fighting to gain slight advantage for aerial challenges in the box on corner kicks. Wayne Rooney is infamous for pushing off his defender’s near side thigh as he jumps as that gives him momentum while slowing down his defender’s jump point. In American football, there are numerous little hacks to gain or minimize separation.
When a new hack is introduced, there is usually a learning curve by the officials. Some will not see the problem at all, and others will see the action but will decide not to react to the action. This is especially true if the hack is subtle, and if it is isolated to only a few players. However, once the hack has become widespread and correctable by official action, the officials are in an intense selective environment to get good at recognizing the hack and responding to it in a more uniform manner.
Other than that …. open thread
patrick II
I remember reading an article on pitch framing in si or espn a couple of years ago and thought — do they know umpires can probably read too?
I am very old so I also remember an interview with Tommy Heinsohn when he was playing with the Celtics. Tommy explained the various tricks he used to avoid having fouls called. He fouled out of the next two games after the interview was published. Not the smartest thing Tommy ever did.
Richard Mayhew
@patrick II: Oh they can read, but it takes a bit of time to adjust what the ump will call a strike.
In soccer, there was a re-interpretation of offside a few yeas back. It was designed to give the benefit of the doubt to attacking play. The first few dozen games on the line had me thinking a lot more about player involvement on marginal decisions that previously would have been violations. Now they were far fuzzier and quite a few of the most marginal calls were now clean and fair play.
By the end of the season, I had re-adjusted to what the new interpretation indicated as a valid offside decision but I had to retrain myself.
Jacel
There’s probably motivation for umpires to learn to call a strike zone that matches the automated scan as closely as they can, to reduce motivation to replace human umpires with machines.
jheartney
Forgive me if this is a naive question, but why do you need an umpire calling the strike zone? It seems like a pretty straightforward measurement to make of where the ball is when over the plate, and all you’d have to do is assign x and y coordinates to balls and strikes.
Ex Libris
This brigs to mind something I have been thinking watching baseball on TV the past couple of years. Why don’t they use the obviously fairly-accurate and consistent technology the TV guys use to just call the balls and strikes? They already use technology to re-evaluate all kinds of plays. Having said that, I don’t really want them to do that, but I don’t see why they don’t from a consistency/accuracy stance. Still need umps or officials of some kind to override the swings-and-misses of pitches outside the zone, etc. I personally think it should be all-tech or no tech (and really I prefer no-tech, for football, baseball, and everything – although probably no way to go back to stop watches for swimming races with hundreth-of-a-second differences.)
Dave Ruddell
Here is a master at work…
Kilgore Trout
I umpire high school baseball, and often inexperienced catchers will receive the ball and yank the glove back towards the plate thinking that’s “framing”. At the JV level or in summer ball I’ll usually tell the kid after the game not to do that – “you’re telling me you didn’t think it was a strike either”.
Obviously at the pro level it’s much more subtle – the angle of the glove and so forth. On a low pitch if the guy has to flip the glove over (fingers down) that’s a visual cue that the pitch is low. But a catcher can nab a strike here or there on a low pitch if he catches it “fingers up”.
Great article at Fangraphs BTW, thanks for the link!
RSA
@Ex Libris:
I suspect that the technology would become less consistent if it were used to make calls. If it’s based on visual analysis, it could probably be hacked by the use of ambiguous or confusing visual cues.
The Other Chuck
@Ex Libris: Baseball has stayed in the “no tech” direction, and thank the FSM for that. I can’t stand that strike zone box they superimpose on games. Bad enough on TV without the gratuitous graphics.
The Other Chuck
@RSA: I don’t see how you could confuse the strike camera, especially if there were two of them, which could trivially detect the ball’s location in space to the millimeter. As it is, they’re already using confusing cues to try to confound the ump.
peach flavored shampoo
Part of the lore of baseball is that the zone is somewhat amorphous between different umps. So pitchers have to adjust to that day’s ump’s zone. Better pitchers do that better. It helps that catchers can influence the position of the ball with sleight-of-hand with the glove. It’s these small things that really add value to a particular player and help define why 2 players, ostensibly equal in their skills, earn contracts that are different by tens of millions of $$.
One of the best was Greg Maddux. Guy could adjust to an umpire’s proclivities on a moment’s notice. Pudge Rodreiguez (sp?) was a master of the framing. No surprise they lasted forever and made a mint.
RSA
I’m not very knowledgeable about baseball. Right, the position of the ball is easy. But I was thinking that because the strike zone is defined with respect to the individual batter’s shoulders, uniform pants, and knees, it might be possible to trick an automated system with changes to the uniform or protective equipment or padding underneath. Computer vision systems sometimes have unexpected failure points, as you probably know.
Roger Moore
@patrick II:
Sure they know umpires can read. People have talked about pitch framing for a long time, and it doesn’t seem to have helped the umpires at all until quite recently. Calling pitches is incredibly hard, especially because the pitches are designed to be deceptive. Catchers framing pitches were taking advantages of the limitations of the umpires’ visual perception, and it’s taken a lot of training with newly available tools to help the umpires overcome that. I still think we’d be better off going straight with Pitch/fx rather than relying on the umpire’s judgment of the pitch location.
Lord Baldrick
August Fagerstrom is an excellent writer on the site.
Roger Moore
@Jacel:
The bigger motivation is to make sure that they don’t get replaced with a different human umpire, i.e. lose their jobs. MLB uses the automated data as part of their review process for the umpires, and guys who do poorly are going to have a hard time in their reviews. Even if the umpires are replaced for pitch location, they’ll still need umpires to call the rest of the calls in the game, including swing/no swing at the plate.
Roger Moore
@RSA:
As a practical matter, you’d probably have somebody manually dial in the top and bottom of the strike zone for each batter before the game. The size of the strike zone is supposed to depend on the position of the batter’s body as he prepares to strike the ball, meaning as he’s swinging, not as he’s in his stance before the pitch. That means it depends primarily on his height and the relative length of his legs and torso, not on his batting stance.
It’s not something players can really change much, so you’d only have to measure the players under standard conditions- which could be in nothing but his jock to prevent uniform tricks- to know the correct height for the bottom and top of the zone. And, of course, the strike zone is part of the rule book, so the league could change the definition in ways that make the height easier for the system if/when they switch to automated strike zone judgment.
RSA
@Roger Moore: Cool, I hadn’t thought of that, a good engineering solution.
Steve in the ATL
@Ex Libris:
Umpire’s union
jheartney
@Roger Moore: Or, you could just add the same visual spots used in motion capture to the batter’s uniform, and get a custom measurement for every pitch.
Tissue Thin Pseudonym
@Roger Moore:
One of the things that made Rickey Henderson so great was that he started his swing while he was still in that exaggerated crouch; as one sportswriter put it, “Rickey Henderson’s strike zone is smaller than Hitler’s heart.”
Prescott Cactus
@The Other Chuck:
Think New England Pats and how much their tech budget would need to increase.
Dave L
@RSA: But there’s another problem: it’s a three-dimensional zone. Those TV graphics can’t really show you whether the ball was in or out of the strike zone when it crossed over the plate, and for pitchers with a lot of motion that can make a huge difference. It’s obviously pretty hard for a human eye to get right, too, but at least umpires have the advantage of stand nearly right over the plate.
randy khan
The strike zone problem is not insoluble for machines, but it’s harder than it looks. It’s not just the variations from batter to batter but, as noted by Dave L, the three-dimensional nature of the zone. So it’s not actually two cameras, for instance, but at least three or four, and probably switching from the left side to the right side depending on who the batter is. Also, batters constantly change their stances (Cal Ripken was notorious for this), so you really couldn’t measure before the season and be sure it would stay right.
And speaking as someone who uses the MLB.com gametracker a lot, the pitch tracker there is not that good. It often puts balls in unlikely places, particularly if they’re outside the strike zone. If that information is derived from the official tracking system, it’s got issues.
I think the real question is what is made better by having an automated system, and by how much. If the gain is not significant, then it’s not worth the bother.
mclaren
Objection! Assumes facts not in evidence.