Thursday, December 20, 2007

What's Good?

I've been reading lately about how the Mariners simply paid the going rate for a good pitcher in today's market as a way of explaining a $48 million dollar contract for Carlos Silva. You know, I don't really have a problem with that in principle - if you want good players, you need to pay what the market calls for, unless you can beg your way into some kind of hometown discount, which is rare.

But I have a problem with the assessment of the notion of "good". What's "good"?

Well, in grading systems - "good" is a B - it's well above average. You're better than the average Joe, but you're not outstanding.

Fortunately, we have a statistic to measure what an average pitcher is, and it controls for what kind of a park you pitch in on any given day - it's called "Adjusted ERA+". If you score 100, you're the exact league average. If you score 110, you're slightly better than average; 90 is slightly below average. Pretty simple.

Examples for you - Paul Byrd, with a 4.59 ERA had an ERA+ of 100. Tim Wakefield, with a 4.76 had an ERA+ of 100. Byrd has the better ERA, but because he pitches in a less-hitter friendly park, his Adjusted ERA+ indicates he's really no better than average - he is Wakefield's equivalent.

Josh Beckett had an ERA+ of 145; Erik Bedard - 146; Danny Haren - 137. They're outstanding. Got it?

So is Carlos Silva "good"? His ERA+ was 103. All things being equal, he's average. Huh. So we're buying average? $48 million dollars for average, not good.

Let's look at the projected Mariner rotation then.

* Felix Hernandez ERA+ 110
* Miguel Batista ERA+ 101
* Carlos Silva ERA+ 103
* Jarrod Washburn ERA+ 100

See a pattern developing? Bill is having a hard time assessing what's good - because according to this, you have yourself exactly one starting pitcher that's better than average.

And that ain't good.

1 comment:

PP said...

Checkout this quote from Bavasi about Carlos Silva in the ESPN article: "I think he's a good fit for any club," Bavasi said. "Guys who get American League hitters out fit anywhere."

At first I thought he was talking about Bedard, but after rereading this he was indeed talking about Silva. A man with a career opponent batting average of .299 "gets American League hitters out." A guy who the league hit .324 against (with a 5.94 ERA) in 2006, "gets American League hitters out."

Give me a break.