HBPs continue to rise-what might be the cause?

See There Is a Hit-by-Pitch Epidemic in Baseball: With pitchers throwing harder than at any other point in history, it’s fair to say there has never been a more painful time to be a hitter by Jared Diamond of The WSJ.

After some excerpts, I will have some links and summaries of posts I have done on this.

"One out of every 96 plate appearances across the major leagues in 2018 ended with a batter being drilled. That was most often since 1900"

The rate of hit batsmen in baseball has varied through the decades, but the trajectory has roughly gone like this: They were most common during the Dead Ball Era of the early 20th century, when batters were more likely to lean into pitches on purpose as a way to get on base. Hit batsman plummeted to all-time lows in the 1930s and ‘40s, climbed after the advent of helmets prompted hitters to crowd the plate with confidence and then dropped again through the ‘80s.

Since then, batters being struck by baseballs have been steadily on the rise, with the frequency exploding in the last couple seasons. This season is on a pace to have nearly 25% more batters hit than 20 years ago.

“You want them to feel uncomfortable at all times,” veteran right-hander Tanner Roark said. “You want to let them know there is a pitcher out there. It’s not just a robot. Every now and then you need that brushback pitch.”"

"One explanation for why batters being hit has become so much more common is simple: an increasing number of pitchers who throw the ball extremely hard—and don’t have much of an idea of where it’s going."

"The numbers bear that out: Starters are hitting batters once every 109 plate appearances this season. For relievers, it’s one every 78 plate appearances."

"Pitchers are throwing inside more than they once did—not to hit batters, but to try to exploit weaknesses they see in them.

“That’s how you get hitters out,” said New York Mets utility man Jeff McNeil, who has already been hit by eight pitches this season. “A lot of hitters have holes in their swings inside."

"In 2008, the first year Baseball Savant offers pitch-location tracking, only 29% of pitches were thrown on the inner part of the plate. This year, it’s nearly 32.5%"

Here are some of my past posts (from way back in 2008):

From More On The Changing Historical Relationship Between Walks, HBPs and HRs

-There is a significant positive relationship between a pitcher's walk rate and his HBP rate

-In the 1960s, a pitcher who gave up more HRs hit fewer batters but today a pitcher who gives up more HRs hits more batters.

From The Changing Historical Relationship Between Walks, HBPs and HRs

-For both leagues, the HBP/Walk rate has been rising since 1980 (so poor control is not the only reason for more HBP).

-In recent years (up through 2007), the HBP/HR rate has been relatively high, even adjusting HBPs for control as measured by the walk rate.

From Do Sluggers Get Hit By The Pitch More Than They Used To?

-players who hit HRs more frequently are now more likely to get hit by a pitch than in the the 50s, 60s and 70s.

-hitting a HR in the 1990s was 83% more dangerous than it was in the 1960s in terms of causing the player to be HBP.

From 2000-2009, here is the equation

HBP% = 0.0477*HR% + 0.009

The denominator for both HBP & HR was AB + HBP. The t-value for HR% was 1.97. The equation from the 1960s was

HBP% = 0.0311*HR% + 0.0058

Since .0477/.0311 = 1.53, it means that hitting a HR from 2000-2009 was 53% more likely to get you hit by a pitch than in the 1960s.