F/X VisualizationsAugust 09, 2010
SABR 40's New Technologies in Baseball Panel
By Dave Allen

Edit: Alan has uploaded PDFs of our talks for download here.

This past weekend I had the pleasure of attending the SABR 40 in Atlanta. I had never been to a SABR meeting before, but was invited to be on the New Technologies in Baseball panel by Alan Nathan. It was a great opportunity to talk with and hear the ideas of the other panel members: Alan; Rand Pendleton of Sportvision; Rob Ristango of Trackman; and Josh Kalk, former THT writer and current Baseball Operations Analyst for the Tampa Bay Rays. It was also cool to meet or reconnect with some people I had usually know only over the internet, Cory Schwartz, Dave Studeman, Cyril Morong, Sean Forman, Eric Van, and the great Rob Neyer.

I thought it would be interesting to give a quick recap of the New Technologies in Baseball Panel. Rand led off and gave a quick history of Sportvision (they started in 1998 and their first big thing was putting the 1st and ten line on NFL broadcasts). He then gave the history of the pitchf/x and hitf/x systems, which have been written about before and I will not rehash here. But then he talked a little bit about Sportvision's new product fieldf/x.

Most of us got our first preview of fieldf/x in last year's NYT article and then at last year's pitchf/x summit. Rand said the system is being tested right now in AT&T park in San Francisco. Like the pitchf/x system fieldf/x uses two cameras, but these cameras have higher resolution than the pitchf/x ones and are framed on the entire field rather than just the pitcher-catcher area. The aim is to track everything on the field: fielders, runners, the ball in play, throws. That is a very exciting prospect and the video from it that Rand showed was very cool. We will know more about the fieldf/x system in a couple weeks at this year's pitchf/x summit.

Next was Rob Ristango who talked about Trackman, that is a doppler-radar system that also tracks the pitch and ball in play. The system was originally designed for golf, where it is widely used, but is now being used in baseball, cricket, and soccer. The system has one radar, high and behind home plate. Rob said that the system is installed and running in a number of MLB parks, when pressed for a specific number by a questioner he responded that the number is greater than one but less than thirty.

Trackman, which measures the location of the ball 48,000 times every second, directly measures the spin of the ball, rather than back calculating it form the trajectory like the pitchf/x system. Based on this Rob showed some very cool data already collected by the Trackman system. For example, curveballs with a higher spin rate had a greater swing and miss rate than those with a smaller spin rate. He also showed that the lower the vertical release angle on a curve out of a pitcher's hand the higher the swing and miss rate. Rob explained that since curves are slower and have more drop coming to the plate than other pitches pitchers have to release them at a higher angle else they end up in the dirt. But if the angle is too high batters can easily tell the pitch is a curve. So the lower the release angle, though still higher than the release on a fastball, the better the deception and higher the swinging strike rate.

Finally Rob said that although the Trackman data is not pubically available if you would like to contact them about your ideas of the data you can get in touch with Josh Orenstein who heads the Trackman Insights Lab (jko@trackman.dk).

I was next and I discussed some of my results on the success of a pitch based on its location in the strike zone. Readers here have surely seen this before and I will not bore you with a rehashing of that.

Next up was Josh Kalk. Josh, a former physics teacher, gave a great prop-based talk on the red dot that appears on sliders. As background he played some audio from an interview Reggie Jackson did on NPR's Fresh Air. On the clip Jackson talked about how good hitters have to be able recognize different pitches, and specifically mentioned the red dot seen on a slider.

To talk about how the red dot happens Josh showed how different pitches spin. Josh had a baseball with a dowel drilled in it. Josh held the dowel out so it was parallel to the lines of seats of the audience. He twisted the dowel back towards himself and told them to picture the ball coming towards them. This was pure backspin, the type of spin you would find on a four-seam fastball and that causes the pitch to drop less than expected due to gravity as it travels to the plate — a rising fastball. Then he twisted the dowel in the other direction, towards the audience. This was pure front spin: the type of spin that causes a pitch to drop more than expected due to gravity, and is found curveball.

Then Josh held the dowel perpendicular to the audience, holding the dowel with the ball out in front of him towards the audience. Again he told the audience to think of the ball coming towards them and he twisted the dowel clockwise (from the audience's perspective). He told the audience this clockwise spin had a rifling effect, this spin will not cause the pitch to 'move' off its initial trajectory and will actually work to keep the pitch on this initial trajectory (like the rifling action of a bullet out of a rifle). The gyroball has this type of spin, and in pitchf/x parlance would have close to 0 pfx_x and 0 pfx_z. Sliders — which tend to have small pfx_x and pfx_z values — have a spin very close to, though not exactly, this rifling spin. Now picture if a seam is facing the batter while the pitch spins this way. Part of the seam will always be right in the middle of the ball as it rifles towards the batter. This will cause a red dot to appear. Because of the way pitchers hold the ball when they throw a slider there will tend to be a seam facing the batter.

To demonstrate this phenomenon Josh had another prop, a ball affixed to the end of a power drill. When Josh fired up the drill the ball spun around and the red dot appeared. Josh slowly panned the drill around so that all members of the audience could get a chance to see it. Unfortunately the ball was not perfectly attached, and part way through the demonstration the ball went flying off, nearly hitting Alan and bouncing under the table were we sat. Some real excitement! Even with the technical difficulties, and maybe because of them, Josh gave quite an informative and entertaining talk.

Alan was up last and gave four examples of new technology in baseball. The first two involved Marinao Rivera, showing his incredible bimodal pitch distribution, which I have talked about here, and then showing how the trajectory on Rivera's cutter gives it the illusion of having late break. Alan then showed, using hitf/x data, how BABIP and HR rate vary by launch angle and exit speed. BABIP peaked at 11 degrees while HRs at 30 degrees. This demonstrated the tradeoff between hitting for average, high-BABIP line drives, and hitting for power, high-HR fly balls. Finally Alan showed how he used hitf/x and Hit Tracker combined to reconstruct the full trajectories of HRs from 2009. With the complete trajectory he could compare how far the HRs actually went to how far they would have a vacuum. He used this quantity to measure the effect environment (wind, temperature, elevation) on fly balls in each park. This was work Alan had presented at the 2009 pitchf/x summit.

All in all it was a great time and very cool to see the work that Sportvision and Trackman are doing to develop new ball-tracking technologies and the work that others (people like Alan, Josh and me) are doing to analyze that data.


Thanks for writing this up, Dave.

Thanks for the name check Dave, great to see you too! Very interesting and informative panel, and like many others, I'm eager to see this technology progress in coming years...

Great to meet you, too, Dave, but my favorite part of the presentation was when the ball flew off the power drill.

Jeremy, no problem. Looking forward to seeing you at the pitchf/x summit.

Cory great to see you too.

Studes, no way I could compete with the ball flying off the power drill.


That was a great panel and it was good to meet you. Glad we did not lose Alan Nathan. I had actually forgotten about that. No doubt Alan went home and calculated how strong the force of the ball would have been if it had it someone. Winston Churchill once said that the most thrilling thing that ever happened to him was getting shot at but not hit. Alan had a Churchill moment.


I wish I could've attended, but, unfortunately, baseball geeks/general geeks decided to schedule the following three conferences on the same weekend: JSM (Joint Statistical Meetings), FanGraphs forum (granted, this was just introduced...) and the SABR convention. The powers that be should work to prevent this from happening... Make a push for it, Dave!