Category Archives: Research

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NPB news: Jan. 25, 2023

On Tuesday night we learned that Hiromitsu Kadota, whose 567 career home runs are third most in Japanese pro baseball, was found dead in his home on Monday at the age of 74.

Kadota was famous not just for his home run total but for the shape of his career. Prior to his age 31 season, he hit one homer per 21.8 at-bats. He then missed most of the 1979 season with an Achilles tendon tear, before having the comeback to end all comebacks, with one home run per 12.7 at-bats through his final season at the age of 44.

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Weighty judgements

I reported last month that over the past 10 years or so, a few teams benefitted more than their rivals in terms of the frequency of favorable pitch calls from umpires. I’d hoped to do a more detailed study of that data, but when I began receiving data sets of each season’s individual pitches, I soon found they needed cleaning, and so that is being done.

In the aforementioned post, I wrote that the raw number of favorable calls is less important than when they come. Taking an 0-0 pitch, while important, is not as big as taking 3-2, where the difference is between an out and a base runner.

Since I have the 2022 data in hand, I was able to answer questions about which teams this year made out the best in terms of the value of the calls they received.

Of course, raw numbers of called balls and strikes are not as insightful as they would be with tracking data. It’s not all about, or even mostly about the umps. The quality of teams’ pitchers and hitters matter.

The parks also appear to have a large impact on the percentage of pitches taken for balls, and why the extreme teams tended to be one-sided, gaining a huge number of runs above average from calls going in favor of either their hitters or pitchers, while being below average the other way around.

To those unwilling to read further for the gory details, I’ll tell you up front that the Hanshin Tigers, Yomiuri Giants and Yakult Swallows got the most total value out of pitches taken by their hitters and against their pitchers in 2022, while I’ll give fans of the Lotte Marines and Hiroshima Carp additional incentive to feel their teams may have been done dirty by the umps.

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