Bumgarner hit hard in spring debut, A's beat Giants 9-4 | Yahoo Sports

I am worried more about this comparison to Hamels circa 2008-2009 than the A's mini-shelling in a practice game. I saw this in a story somewhere and immediately started feeling uneasy. Then the mini-shelling just made it worse. Even though it was in a practice game.

Cole Hamels threw 262.1 innings in 2008 in a World Series MVP season. The following season was the worst of his career (4.32 ERA, 1.286 WHIP). 

from Yahoo Sports:
Bumgarner hit hard in spring debut, A's beat Giants 9-4 - Yahoo Sports:

"Right now I'm not worried about results," Bumgarner said. "It's about getting my body back in the rhythm of making pitches, and competing. You want to get guys out, but it's more about getting my arm in shape."

'via Blog this'

Some of this is carry over from this blurb from the book Baseball Between the Numbers:

One of the earliest analyses of historical trends in pitcher usage was the landmark 1989 book The Diamond Appraised by Craig Wright and Tom House. The authors looked at pitchers of various ages and their workloads and discovered that young pitchers who pitched to a high number of batters per game seemed to get hurt more often. This was the beginning of the modern movement to monitor pitch counts.

In the mid-1990'2 Baseball Prospectus's Rany Jazeyern was one of the first researchers to try to organize and codify what the mishmash of evidence on pitch counts was telling us. He summed it up in his principle of pitcher fatigue: Throwing is not dangerous to a pitcher's arm. Throwing while tired is dangerous to a pitcher's arm.

All this statistical (over)analysis led to things like pitchers abuse points (PAP), and the dreaded Verducci effect which states:

Last week, Sports Illustrated writer and Jason Parks man-crush Tom Verducci put out his annual column warning about a specific type of player: A young pitcher (25 or younger) who saw a significant increase in his workload in the previous season over the season before that (defined as an increase of at least 30 innings, including postseason and minor-league work). Verducci claims that this sort of pitcher is in danger of either a significant injury and/or a performance decline in 2013 because his 2012 was much busier than his 2011. It's a proposition that's become known as the Verducci Effect.

From a rational standpoint, I should be comforted by this article which should have put a Dr. Kervorkian on the Verducci Effect (also dubbed the Year After Effect) but some of these old statistical theories die hard. Funny how that works, since the SABR folks often accuse baseball folks of the same mentality of clinging on to past theories even after they have long out-lived their utility.

And I'm still going to worry about Bumgarner just a little bit, but I'm going to wait until real-live hitters hitting in real-life situations tell me something different about him.

How perfectly old-school can you get?

from Deadspin.com
http://deadspin.com/5877565/the-verducci-effect-is-overworked-and-broken-down

Sports Illustrated's Tom Verducci came out with his annual "Year After Effect" column yesterday, based on his hypothesis that that young pitchers tend to break down the season after an increased workload. Specifically, a pitcher 25 and under is supposed to be at risk if he pitched at least 30 more innings than his previous career high.

Dubbed the "Verducci Effect" by Will Carroll at Baseball Prospectus, it's one of the most prominent early examples of a happy marriage between analytics and old journalism. Sabermetricians were some of the loudest critics of the overuse that may have contributed to the early decline of Mark Prior, Ben Sheets, and other pitchers who debuted in the early aughts.

But the Verducci Effect probably doesn't exist. Its continued popularity has little to do with the power of numbers to support rational observation and everything to do with their power to baselessly reinforce existing beliefs. The article is an example of three pervasive mistakes that the general public makes about statistics:

• Regression to the mean: When an outcome is far above or below expectation, the subsequent results tend to be closer to the average. How does a young pitcher make Verducci's list? By having been healthy and successful enough to earn a greater workload. So by chance alone, you'd expect some members of that group to pitch worse, and you'd certainly expect to see some of them get hurt. Derek Holland's good health allowed him to pitch 71 more innings than he ever had before. If he gets sidelined in 2012, it will have more to do with the random nature of injuries than with Rangers mismanagement.

• Confirmation bias: People tend to rely on anecdotal examples that confirm what they already think. There's little attention paid to the pitchers who repeat their healthy seasons the year after; instead, fans fixate on the ones that get hurt. Mets fans might look at Jon Niese's 2009 injury and point to Verducci's warning label. They'd be ignoring the fact that no other pitcher that Verducci identified in '09 spent a single day on the disabled list.

 • Correlation does not equal causation: Verducci is correct that some pitchers who pitch 30 innings more than their career highs tend to get hurt. However, that doesn't mean that his rationale for why that happens is valid. After I read his article, I went to the bathroom and peed. That doesn't mean I peed as a result of reading.

Every study I could find on the Verducci Effect suggests that it at best doesn't exist and at worst is backwards. David Gassko's 2006 study focused on the possibility of a decline in performance, and found an increase:

OK, so what happens if we limit ourselves to pitchers who threw at least 100 innings in year two? Actually, a funny thing. The pitchers who best their career high by at least 30 innings go on to throw 90% more innings in year three than they do in year one, and those who didn't only throw 78% as many innings. What's more, while the [year-after effect] candidates have an ERA 9% lower in year three than it was in year one, the guys who were accustomed to the big workload do not improve their performance at all.

Much ado about nothing.