Relay Tour

We've all seen it. During a golf telecast a little box appears on the screen telling us how far a particular shot went and how far the ball lies from the hole. Ever wonder how they get those yardage details?

It's a system called ShotLink, developed by IBM for the professional golf tours, and I'm going to tell you why you can't always rely upon what you see or hear but first, a rundown of the ShotLink system itself.

Real-time data during every tournament round is collected in a processing center (a really cool trailer, actually) where it is then crunched and delivered to the TV production crews for use in the broadcast. And if you weren't aware, all of that information is available to you and me as well. Go to the PGA Tour website and search for ShotTracker. Then follow the golfer or group of your choosing. (FYI--the service is NOT available during the U.S. Open. Bummer, I know.)

So where does this shot-by-shot information come from? Two main sources, both of which are served by volunteers who work at each tournament.

If you ever get the time and the opportunity to volunteer to work at a PGA Tour event I would highly recommend doing it. It is a lot of work, but it is well worth the effort and for the average golf fan, this may be one of the only ways you can see tour players up close!

First, every group is followed by a walking scorer. The walking scorer is armed with a customized PDA which allows them to enter the player, club used, shot result and more.

Second, at landing areas in every fairway and at each green will be a team of laser operators. Once each shot has stopped, the laser operators zero in on the ball and target its exact position. Triggering the laser relays the information on the ball's coordinates which then tell the processing center the shot's length and remaining distance to the hole.

For the most part, the laser readings are very accurate.

To address a broken or malfunctioning laser, each team is given a laminated map of their hole and station as a backup. These maps have a finely detailed grid on them. If for some reason you cannot use the laser, you can still find the ball position on the grid and relay the coordinates to the command center over the radio.

The fairway grid maps have coordinates that measure roughly 5 yards square, and there are quite a few "known" points (sprinkler heads, drainage areas) from which one can get a good idea of the ball's position. The green grid maps are much smaller, and there is little on the green to help identify on exactly which coordinate the ball rests. Because of this, making an accurate greenside reading is very difficult.

The August 22, 2007 USA Today contained an article on the ShotLink system. Fred Funk summarized the challenges quite well. "The only downside to it", said Funk, "is that sometimes the person that's taking the measurements isn't real accurate. My wife will say, 'Why did you miss that three-footer?' I go 'three-footer? That was a 15-footer.' It's only as good as the person using the machine doing the measuring."

And therein lies the reason we can't accept all ShotLink data as accurate. Volunteers do their best, but for many reasons their readings aren't always accurate to the extent that television suggests.

I was fortunate enough to volunteer at the 2005 President's Cup tournament where my job was a fairway laser operator. Several times during the tournament our readings became inaccurate, either because the laser was not working or because the calibration had slipped for one reason or another. For about an hour on Day 4, the laser was not usable and so we had to plot the ball positions manually using the fairway grid.

Were we accurate? I'd say yes within 5-6 yards, but I'd be willing to bet none of you heard Gary McCord say, "Johnny, we're in the 16th fairway and after a beautiful tee shot, Vijay has somewhere between 167 and 175 yards to the pin but...we're not exactly sure. Let me get back to you after we check the map."

Now I'm not at all being critical of the ShotLink system or of the volunteers who run it. I love the data and am constantly looking through the statistics to see what a particular player averages off the tee or what their average distance to the hole inside 100 yards is. Just remember that everyday folks like you and me are providing those numbers, so once in a while you'll see a reading that's a little bit off.