Originally Posted by flyer85
the average is around 10% ... and the pitcher generally has little control as s tends to fluctuate from year to year. It was one reason I was so bearish on Stanton in 2007, he a 2% rate.
Reds relievers due for a correction in 2008?
Weathers 4% in 2007, Burton 4% and Coffey 18%.
The guys you chose actually represent a case study in how to interpret HR/FB% with many of the caveats IMHO.
First just a few general thoughts about HR/FB. When looking at HR/FB%, starters have to be considered separately from relievers largely due to the effect of role. Relievers generally have lower HR/FB rates than starters (each group regresses to a different mean) and it's not uncommon for a good bullpen arm to have a HR/FB half of what a starter might have.
That said, not only did Weathers have a low HR/FB rate in '07 but more importantly it was an obvious departure from his career norms (9.7%) which does suggest he'll regress to the mean in '08 in that regard. Looking at Weathers' last three years, it's clear that he's aging into a FB pitcher who pitches to contact as he's losing velocity and his slider seems less bitey. It's reasonable to wonder if his HR/FB rate of last year masked his decline. I'm very concerned by the notion that the Reds consider Weathers their 8th inning guy next season.
Concerning Stanton, he's an example of relievers generally having lower HR/FB rate than starters as his HR/FB rate of 7.5% in '07 was very consistent with his career average of 6%. The issue with Stanton isn't that he's due to regress to the mean. Rather, Stanton at this point in his career is just an arm. His peripherals suggest middle reliever. He hasn't had platoon splits to suggest he'd be good as a situational guy for a couple of years. What's worse, the Reds are on the hook for a minimum of $3.5M for Stanton while they could expect to get similar production from several arms in their own system at the cost of league minimum. Stanton is a pretty glaring inefficiency on the roster IMHO.
Coffey is another interesting case of HR/FB%. While positive swings in "luck/unluck" splits usually suggest a regression to the mean is likely to occur, really poor ones aren't necessarily indicative of bad luck. For instance a pitcher who is done will often have high HR/FB rates, high BABIP and an low LOB% (that trifecta is a sure sign a guy is done actually). There was something up with Coffey last season that informs his BABIP and HR/FB rates (here's
my thoughts but reading the whole thread, it's clear others have alternative explanations). We weren't just seeing the effects of bad luck IMHO(because his changed miraculously between the majors and Louisville). That said, he's young and clearly still has his velocity. He could rebound but it'll be due to some change he makes and not a reliance on his luck evening out.
Burton is another interesting case. His HR/FB rate might regress a bit but we really don't have enough information to know his true mean (though he has had low HR allowed rates in the minors). There's just not enough context for Burton to draw inferences from his HR/FB% (so here we have to consider sample size issues). To me the biggest worry about penciling in Burton for a role in high leverage situations was his command issues of '07. That said, he didn't show similar issues in the minors. Also, I'm not convinced he'll be as devastating against lefties as he was in '07. Truthfully I'm not sure what Burton throws in addition to his fastball. He came to the Reds billed as a sinker/slider arm but his pitch f/x data is just weird (albeit a small sample size). He looks pretty unique but it appears to translate. Nonetheless, he's got to be considered a question mark.