Arthur/Lindbergh: The home run is back, and no one knows why
From SABR members Rob Arthur and Ben Lindbergh at FiveThirtyEight on March 30, 2016:
On his first day in office, in January 2015, Major League Baseball Commissioner Rob Manfred announced his interest in “inject[ing] additional offense into the game.” Over the previous several seasons, scoring in baseball had dropped to levels not seen since the mid-1970s, as an expanded strike zone, an increase in average pitch velocity, the rise of defensive shifts, and detailed data on batter tendencies had combined to keep runs scarce. Manfred mentioned banning the shift as a possible solution to the scoring decline, and he considered shrinking the strike zone and adding the designated hitter to the National League. But he decided to see whether the trend persisted before taking action.
After the 2015 season, Manfred congratulated himself on his earlier restraint. “What I said at the beginning of the year was that, before we made a judgment and started to talk about changes, that we needed at least another year of data,” Manfred said. “Every once in awhile, even I get to be right.”
He was right: Just as it began to seem certain that only a deus ex Manfred could rescue the sport from soccer-esque scores, baseball’s offense came back from the brink. The only problem is that no one knows why, or whether it will last. To unravel the mystery, we examined the most likely suspects — warmer weather, better rookie bats and bouncier baseballs — completing our investigation by shipping a bushel of balls to a laboratory for testing.
Read the full article here: http://fivethirtyeight.com/features/a-baseball-mystery-the-home-run-is-back-and-no-one-knows-why/
Originally published: March 30, 2016. Last Updated: March 30, 2016.