For those of you who’ve been following this thread of research into called balls and strikes in NPB from 2009 to 2022, I’ve got a conclusion for you: The chance of the Yomiuri Giants, in the nine seasons from 2009 to 2017, doing as well as they did getting called strikes in 1-0 counts on talent alone is next to zero.

I started this investigation with the observation that the Giants pitchers got an abnormally high percentage of called strikes in some counts between 2009 and 2022. These results came from a data set received from ScoutDragon.com’s incomparable Michael Westbay.

Upon further investigation, it became clear that 2018 was a subtle watershed in NPB.

Since that point several teams diverged from their previous called-strike results relative to the other teams in their leagues. That year, 2018, was when 11 of the 12 teams, having successfully installed Trackman pitch-tracking systems, began sharing that data with NPB for the purposes of “umpire development.”

It would be overly cynical, even for me, to attribute much of the shift to umpires suddenly being just becoming slightly more diligent, since teams and players are always changing. Much of it was likely due to shifts in teams’ talent bases and approaches, while some of it was likely just random noise.

It was, however, obvious from the start that would have been impossible for an ordinary average team to achieve anything close to what Yomiuri did from 2009 to 2017.

Former ump Osamu Ino attributed the Giants’ extreme success in getting called strikes to the extreme high quality of their pitching staffs. When he said that, however, I had no way to measure how likely it would have been for a team that was nearly always the best in the league at getting called strikes on talent alone.

To see if Ino’s assertion was reasonable, I created a program that constructed normally distributed leagues. Of course, not all teams have equal access to talent, particularly since some, like SoftBank, are really good at developing it, or like Yomiuri, are really good at maintaining a system that increases their access to amateur talent at the expense of other clubs.

Still, if you take a collection of teams, throw them into a six-team league, their results in any area will be normally distributed. The model I eventually settled on assigns teams an annual chance of getting called strikes is based on their ability to actually get called strikes relative to the league from 2009 to 2017.