Accuracy of TBS's Version of K-Zone
 

I'm kinda wondering if the strike zone tool that TBS is using for its telecasts is accurate. I'm seeing a lot of pitches that are just nibbling that zone not getting called strikes, and also more than I would expect that are missing it by a pretty significant distance are being rung up.

Maybe it's because the graphic stays on for every single pitch as opposed to just being shown during the replay of a questionable call.

I did see one pitch (can't recall which game) where the catcher set up on the inside corner of a righty batter, and the ball went towards the outside such that the catcher had to reach across his body and backhand it. The umpire called it a ball, but the graphic showed that the pitch was right in the middle of the zone. :p

The umpires are calling strikes. I think it's great!

But they're calling pitches strikes that aren't close to the zone, and they're calling pitches that are in the zone balls, if you believe the graphic is accurate. I want to think these guys are calling solid zones, and the graphic isn't giving them any justice.

There's a list of the plate jobs and links to the pfx computer charts here:

Close Call Sports

DeMuth last night missed 6 pitches out of 133 according to the computer, which is a darned good performance.

He also wore a long-sleeved undershirt under a short-sleeved jersey, which looks tacky at any level.

OK what am I missing here?

Its only arithmetic.

18 half innings with avg 4-6 batters per, is approximately 90 batters.

90 batters at avg 5 pithches per batter is 450 pitches.

This rating system is judged upon 1/4 of the HP calls?????

What am I missing?

Part of what you are missing is that it does not judge on any pitch that is swung at. Not sure that accounts for 100% of the discrepancy, but it has to account for a majority.

As near as I can tell, this only tracks where the pitch is caught. It doesn't track the path of the pitch through the zone. Does anyone know this for sure?

I've seen pitches that appear on the tracker higher than they were caught. I would think they have multiple cameras measuring this and can fairly accurately know when the ball crosses the plate. That's what Questec did/does.

I'm not "for sure" on this, but I'm kinda sure.

My understanding is it uses 2 cameras which are aimed perpendicular to each other and feeding data into a computer which tracks the ball via shape recognition software and records the 3 deminsional path (actually an approximated path derived from 20 or so points).

It is also my understanding that the inner and outer edges of the strike zone are fixed to the edges of the plate but the upper and lower extremities are adjusted for each batter according the the size of the batter. No adjustments are made regarding the batters position relative to standing in the front of the box vs. the back of the box.

It is also my understanding that the "digital strike zone" is a plane at the front of the plate rather than a theioretically correct pentagonal prism.

All this is based upon what I have read and not based on first-hand knowledge.
The bottom line is , in my opinion, this has forced umpire to call a more consistant, rule-correct strike zone and we don't have any Eric Greggs (RIP) with a 3 foot wide strike zone.

My 12 year old son commented Sunday night during the Reds/Giants game how good the HP umpire was at balls/strikes.

Umpires are not judged on obvious strikes or balls. There's probably a bit more to it...but my point is that you have to get your money pitches. If you get 10 correct that are cock shots, and miss one border one, 90% is not a true indictor of how good of a job you're doing. Let's take 10 border pitches and say you got 9 of them right, now that's a nice job.

Agree. But the pfx graphs linked in Rich's post above capture a lot of pitches that are your so-called "cock shots".

A better assessment would include the graphic display of only those border pitches, plus the no-brainers that the umpire still got wrong.

I looked at the stats for several of the games this week, and it appears to me the discrepancy is easily accounted for simply by subtracting the pitches swung at - more than half the pitches were swung at, in total, in the 5 games I checked.

Interesting.

Eric Gregg was the first umpire I saw do that. Jerry Crawford also did it. Of course he never wore a coat behind the plate. I am surprised they let DeMuth do it considering over the last five years MLB has had a minor crackdown on player and umpire wardrobe, but I like it. It would be better with the blue shirt and the black long-sleeved undershirt.

No thanks. On days where I don't want to wear a jacket, I prefer wearing a long-sleeve umpire shirt. Short-sleeve shirts with long-sleeve undershirts are okay on player unis, but they just don't look good on umpires.

But that's just me. And I guess MLB umpires don't have the long-sleeve option.

Ron Kulpa (a STL native) came to talk to our local association that he used to be part of before he got into the game, and he told us that the pitch tracker things shown on TV are not very accurate, nor the ones that MLB umpires are evaluated on.

What a surprise.

If he admitted they were accurate he would be admitting there are a lot of missed calls.

GMAFB. It looks like crap no matter who does it.

No system that represents the pitch as a point and the strike zone as a rectangle can possibly be accurate. Both the pitch and the zone are three-dimensional objects, and plotting a point on a plane simply will not provide enough information to evaluate the accuracy of a strike call (or non-call).

From what I've read up on the pitch f/x the actual tracking of the ball (from release of the ball to it being caught), along with other information gathered (horizontal/vertical change, release speed, spin) is accurate to a high degree (with the knuckle ball being the outlier as far as ability to track a pitches full movement from release to catch). The issue with all this is how the strike zone is represented with each different pitcher.

So you have just confirmed the inaccuracy of the entire system. The track of the ball is accurate however, relative to its placement in the strike zone, well that may or may not be so accurate. Which means the over all accuracy of the system may, or may not be that accurate.

As an Engineer, thats unacceptable.

Now, they just need a glowing, floating ovoid to represent the strike zone, and we'll have it!

They already exist in the shape of sports announcers. There definetly floating out there somewhere.

Exactly. The strike zone is a cube at the very least.

Rita