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Daily coverage of the Mariners during the season and all year long.

March 4, 2007 at 8:01 AM

Are Mariners pitchers predictable?

A beautiful Sunday morning here in Peoria as we prepare to head to nearby Scottsdale for today’s noon (PST) encounter with the San Francisco Giants. Don’t know if you’ve caught up on all the Times baseball coverage today, because there was tons of it. Some good news for Mariners fans looking for some after three straight losses to open the spring comes courtesy of colleague Larry Stone. Gee, I hope he’s right because I’d hate to see the Angels run away with the division. After so many years covering the AL East, I want to see a race involving somebody other than the pre-season favorites.
Jerry Brewer finally asks Richie Sexson about something that made me giggle (yes, giggle) when I first arrived here last September and glanced at his bio in the media guide. Sexson got it as a tribute to his grandfather, by the way.
One cost of all this coverage is that I really didn’t have the space to do justice to a story on Mariners “numbers guy” Mat Olkin, who I had a really interesting conversation with by phone last week. Olkin was responsible for creating the “Predicted ERA” stat, though he graciously lays all the credit at the feet of baseball stats guru Bill James. It was the work of James and others that led to the “Runs Created” formula to judge the value of hitters.
What “Predicted ERA” does is essentially the same thing for pitchers. James did the bulk of the legwork, but Olkin finalized the product, which, by the way, is how roughly 99.9 per cent of all inventions in this world usually wind up happening. My goal is not to turn this blog into a stats-laden think-tank that will bore the heck out of the average reader. But there are certain stats in baseball that are very important to the outlook of a team and the Mariners did hire Olkin on a freelance contract basis in 2005 so I think even traditionalist, stats-phobic fans will learn something here.
Predicted ERA is based solely on the relationship between a pitcher’s on-base and slugging percentages against and the earned runs he allows to score. This is very different from regular ERA, where all kinds of random factors can inflate the final stat for reasons beyond a pitcher’s control. In other words, if a Predicted ERA is much higher than a pitcher’s regular ERA, it could be a sign that the guy on the mound got lucky and that his regular ERA is about to soar the following season. Conversely, if the Predicted ERA is much lower, that pitcher may have some real hidden value that will become obvious to everyone the following year.
Here’s what I would want to know if I was a Mariners fan. How do the Predicted ERAs of the Mariners’ starting pitchers look versus their regular ERAs? Let’s see. We’ll put the Predicted ERA first, then the regular ERA in brackets, then the difference between them.
Felix Hernandez — 4.05 (4.52)… – .47
Jeff Weaver — 5.69 (5.76)… -.07
Jarrod Washburn — 4.41 (4.67)…-.26
Miguel Batista — 4.66 (4.58)…+.08
Horacio Ramirez — 4.33 (4.48)…-.15
Well, that’s some pretty good news. Hernandez’s number kind of jumps out at you a bit and that’s a positive sign. Even Washburn likely wasn’t as bad as some of his numbers looked last season and could show improvement. Everyone else is pretty much level. The variances we’re seeing aren’t enough to really make a difference one way or another and I’m sure Mariners management will be happy not to have any big negative ERA surprises this season.
Don’t forget, there are all types of other factors Olkin and the team considers in acquiring or trading a pitcher. Predicted ERA is only one of them. It’s a good tool, but not the be-all, end-all stat. Ramirez and Batista are both coming over from the NL, so their ERAs may have a tendancy to jump a quarter of an earned run or more. Consequently though, Batista spent the past few seasons with questionable defense behind him in Toronto and Arizona (save for second baseman Orlando Hudson in both places). Arizona also has some of the shortest infield grass in the majors, leading to more grounders getting through the infield for pitchers like Batista. That is why any solid research cannot be based solely on stats. I’m curious to see whether Batista can vastly improve his numbers in Seattle because of the field and the defense, regardless of the NL-AL switch.
Still, this is a good stat and makes for fun reading and speculation.
Let’s check out Washburn’s numbers after his final season with the Los Angeles Angels in 2005:
Predicted ERA: 4.27
Regular ERA: 3.20
Difference: +1.07
Whoa! Did we just read that correctly? After all, the Mariners already had the guy who invented Predicted ERA on their payroll and still went ahead and committed four years, $37 million to Washburn.
So, how did the Predicted ERA “predict” in Washburn’s case when it comes to his regular ERA totals in 2006?
Washburn’s 2006 ERA: 4.41
Washburn’s 2005 ERA: 3.20
Diffrerence: +1.21
Oh my…it did predict correctly. So, what happened here? Did Olkin take a sabbatical when the Mariners were out shopping for free agents?
All I can tell you is that the Mariners are looking at more than one thing when they go after pitchers. Olkin is too professional to comment on any individual player and what his recommendation may have been. His voice is also just one of many that GM Bill Bavasi listens to on player decisions. And don’t forget, Predicted ERA is not the only stat Olkin uses to arrive at that call. He’ll also look at things like durability, a pitcher’s record against certain types of hitters, in certain situations. And Predicted ERA, as good as it may be in some cases, is not an exact science. No stat ever is.
That said, though, it does make for interesting reading and speculation. Told you.



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