Slashdot Mirror
A Computer Umpires Its First Pro Baseball Game
An anonymous reader writes: Baseball has long been regarded as a "game of inches." Among the major professional sports it arguably requires the greatest amount of precision — a few extra RPMs can turn a decent curveball into an unhittable one, and a single degree's difference in the arc of a bat swing can change a lazy popup into a home run. As sensor technology has improved, it's been odd to see how pro baseball leagues have made great efforts to keep it away from the sport. Even if you aren't a fan of the game, you're probably familiar with the cultural meme of an umpire blowing a key call and altering the course of the game.
Thus, it's significant that for the first time ever, sensors and a computer have called balls and strikes for a professional game. In a minor league game between the San Rafael Pacifics and the Vallejo Admirals, a three-camera system tracked the baseball's exact position as it crossed home plate, and a computer judged whether it was in the strike zone or not. The game went without incident, and it provided valuable data in a real-life example. The pitch-tracking system still has bugs to work out, though. Dan Brooks, founder of a site that tracks ball/strike accuracy for real umpires, said that for the new system to be implemented permanently, fans must be "willing to accept a much smaller amount of inexplicable error in exchange for a larger amount of explicable error."
Thus, it's significant that for the first time ever, sensors and a computer have called balls and strikes for a professional game. In a minor league game between the San Rafael Pacifics and the Vallejo Admirals, a three-camera system tracked the baseball's exact position as it crossed home plate, and a computer judged whether it was in the strike zone or not. The game went without incident, and it provided valuable data in a real-life example. The pitch-tracking system still has bugs to work out, though. Dan Brooks, founder of a site that tracks ball/strike accuracy for real umpires, said that for the new system to be implemented permanently, fans must be "willing to accept a much smaller amount of inexplicable error in exchange for a larger amount of explicable error."
The article didn't suggest ball tracking was new, I'm not sure what led you to believe it did. It was about computers making the decision in professional sport, which afaik is new.
Cricket is actually a poor comparison as Hawkeye is used to predict where the ball would have gone, whereas in Baseball you're looking at where the ball went and defining whether it passed through the correct window. This should make it a lot less controversial as there's no debate about whether the computers extrapolation is correct or not, like there is with hawkeye in cricket.
The use of a computerized system to call balls and strikes is not new to professional baseball. Major league baseball has used a system called QuesTec to automatically determine whether a pitch is a ball or a strike. MLB used the data to evaluate the performance of umpires and try to standardize the strike zone so that all umpires call it according to what's in the rule book. In practice, this generally meant a narrower but a taller strike zone, including calling the low strike at the knees and the high strike at the letters. Another system called PITCHf/x is installed in all 30 MLB parks and automatically classifies the type of pitch and tracks its trajectory, recording both velocity and movement. This data can show which pitches were balls and strikes, the type of pitch thrown, the velocity, and the amount of horizontal and vertical break on the pitch. These data are readily available on sites like Fangraphs. Furthermore, the K Zone and FoxTrax have been regular parts of the ESPN and Fox MLB telecasts, respectively, for many years and show the trajectory of the ball as it's pitched and whether it's a ball or a strike. The technology isn't new at all to professional baseball. The only thing that's actually new is using the data in real time to umpire a game as opposed to evaluating umpires after games, collecting data sets for scouting and statistical analysis, or entertainment purposes in TV broadcasts and tracking games live online.
The thing is, I'm not so sure that I, as a fan, want to see the human element removed. Expanding the strike zone is a skill and a part of the sport. It's also a skill when the batsman shrinks or crowds the strike zone. The ability to adjust to a slightly different strike zone every night is also part of it.
Of course, none of this gets the ump out from behind the plate. There's still the swinging strike to consider. I don't know of any machine that can make that call automatically. For that matter, there isn't even an unambiguous rule for what counts as a swing, so there would have to be a rule change to even allow a machine to make the call unofficially. Even if that is taken over, there's still the foul tip and hit by pitch that the umpire will need to call. Not to mention plays at the plate.
There's an interesting oddity to the way umpires are currently graded with pitch F/X. Pitches that cross the front of the plate at the batter's knees but then drop before reaching the catcher are strikes by the definition in the rulebook. Those pitches don't look like strikes to the casual observer, so umpires stopped calling them strikes, basically so they don't get yelled at. Batters know this and generally position themselves at the extreme back of the batter's box to give themselves the most time to react to a fastball.
The automatic system currently grades umpires with the standard that balls and strikes have traditionally been called, NOT with a strict adherence to the actual rulebook zone. So when the MLB implements the automatic balls & strikes, will it be the actual strike zone or the traditional zone? Robot umpires don't care when people yell at them. If it's the actual rulebook zone, pitches that bounce before the catcher will be called strikes. Batters will have to adjust by moving up in the box to hit that low curve ball.
-Dave
3 to 5 years? I was a catcher in little league in the '70s and was taught how to frame pitches. It's been done as long as there have been umpires calling balls and strikes...