According to Statcast, this past Saturday Kris Bryant hit the longest home run in Major League Baseball this year. The home run traveled 495 feet with a batted-ball speed of 111 mph and an angle of 33 degrees. The ball careened off the newly installed scoreboard in left field.

Aside from watching the replay, to put the home run into context, I created a hexbin plot that shows Bryant’s home run as an outlier. This graph includes only home runs for which Statcast has published batted-ball data and also were recorded as featuring a distance of 300 feet or greater. (This data set contains only about 75% of total home runs in 2015.) Each hexagon is a bin consisting of a batted-ball speed range and a batted-ball distance range. The color represents how many home runs fall into that bin; the more blue a bin is, the more home runs fall into it. The lack of the bin indicates no home runs for those data points.

Kris Bryant is right at the top in his own hexagon. According to Statcast, he has the longest home run, but his batted-ball speed is not the fastest for a home run this year. That distinction belongs to Giancarlo Stanton with a 119 mph exit velocity. If you check another home-run data set, ESPN’s Home Run Tracker, you actually will get a different estimate for Bryant’s home run – 467 feet with a speed off the bat of 112.6 mph and a 28.2 degree vertical launch angle.

I’ve recreated the hexbin plot with the ESPN Home Run Tracker data set. This time Kris Bryant’s home run doesn’t stand out and Josh Donaldson has the fastest speed off the bat.

ESPN Home Run Tracker estimates the distance using the initial parameters of batted-ball speed and launch angles, and then adjusts for atmosphere conditions and the ball’s end point. Statcast has a more sophisticated, real-time trajectory tracker measuring the position of the ball throughout its flight.

This isn’t to say Statcast is perfect while Home Run Tracker is flawed. Statcast has a partial public data set that has some rather glaring examples of bad data, in which (for example) 31 home runs are reported to have traveled less than 300 feet. ESPN Home Run Tracker has only six home runs travelling under 300 feet with three of them being inside-the-park home runs and three being missing data points. This is why I limited the graphics to home runs that were measured at 300 feet or more. As with any tool there are flaws, uncertainties and biases. Any thorough comparisons between the two data sets would require more space than I have here.