(Still) The Most Volatile Hitter in Baseball History – FanGraphs (blog)

Last week, on Twitter, Mike Petriello reminded me that, in January of 2016, I wrote a post entitled The Most Volatile Hitter in Baseball History. The headline was sexy and interesting, because I didn’t know any other way to convince you to read a post about Ryan Raburn. The gist: I looked at all four-year season stretches dating back to 1900, with at least 200 plate appearances in each season. Raburn, over his four-year span beginning in 2012, had seen his wRC+ bounce around the most. He went from being one of the worst hitters to being one of the best hitters to being one of the worst hitters to being one of the best hitters. I don’t know what it meant. It just instantly became the most interesting thing about Ryan Raburn.

Okay! So, since 1900, there have been more than 8,300 cases where a player was a “qualified” hitter in consecutive years. Who had the biggest year-to-year drop in wRC+? You might be able to guess this one — it’s Bryce Harper, who just saw his wRC+ drop by 85 points. Though he wasn’t bad by any means in the most recent year, he wasn’t the destroyer of worlds he’d been the summer before. Rumors continue to swirl that Harper was playing through significant pain.

Bryce Harper’s wRC+ just lost 85 points. A massive, historic drop. If you look at the last two years and reduce the playing-time minimum, the guy with the second-biggest drop, at 81 points, is Ryan Raburn.

The pattern, therefore, continues.

The first time around, I looked at four-year stretches, with a minimum of 200 plate appearances in each. Raburn has batted at least that many times every year since 2009, but since he’s often been close to 200, I opted to lower the minimum to 150 plate appearances. Now to look at five-year stretches. I had a pool of 12,044 five-year stretches to consider. Here are the stretches with the biggest wRC+ standard deviations:

It’s Ryan Raburn! In second place, overlapping Ryan Raburn. In third place, overlapping Ryan Raburn. And then a somewhat distant Dusty Rhodes. But one thing about standard deviations is that they don’t really consider sequencing. Going 100 – 100 – 50 would look the same as going 100 – 50 – 100. The second example looks more volatile, so to capture that, I’ve looked at the total wRC+ change. I took the absolute values of the changes between each year and then added them together. The leaders:

It’s not even close. Over the last five years, Raburn’s wRC+ has changed by an average of about 101 points a season. The nearest non-Raburn name is 2011 – 2015 Danny Valencia, at an average of about 69 points a season. Raburn established a historic pattern, and then continued it. I wasn’t expecting that, even though, you know.

Basic pattern recognition would suggest Raburn is now due for another offensive breakout. He happens to be a free agent, and the last time he was linked on MLB Trade Rumors was last March 29. Every team in baseball would tell you, no, that conclusion is stupid, that’s not how this works. But I think we can all agree that baseball probably doesn’t quite understand how Ryan Raburn works. How could it?