Technology is now defining the strike zone.

From American Public Media, this is Marketplace Tech.

I'm Stephanie Hughes.

In baseball, calling balls and strikes is a kind of art form. Here's the late umpire Dutch Renard,

making a very audible call during the 1989 World Series.

Now a little more science is being added to the artistry. Major League Baseball has introduced

the automated ball strike challenge system,

or ABS. If a batter, catcher, or pitcher disagrees with the human umpires call, he can tap his hat.

Then the ABS system uses cameras to say whether the pitch was indeed in the batter strike zone.

I spoke about this with Nola Aaga, professor of sports management at the University of San Francisco.

If you know baseball, you know that there's a strike zone. And like the plate, it's 17 inches wide.

And what we have now is digital technology, he uses cameras, to create a digital perspective of where a ball is moving through that strike zone. So Major League Baseball

has been working with a company called Hawkeye, and Hawkeye has been doing ball tracking since 2001.

And so in order to perfect the strike zone in Major League Baseball, they did years of testing.

And what they realized is the top end of the zone needs to be 53.5% of a player's height.

And the bottom is 27% of a player's height. So it's very, very specific. And you can tell that they did a lot of

testing in order to get those very specific measurements. Why do you think Major League Baseball is adopting them?

They really have no other choice in a digital world.

So as fans, we are used to seeing a line on our screen that follows the ball from a batter's bat to the outfield.

We're used to seeing it in golf.

We're used to seeing it in tennis.

We're used to seeing it in the NFL.

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