EWSL Rookie Adjustments

In Part II of my look back at how Established Win Shares Levels fared in 2006, I’m taking a look at the rookies. Rookies – players with no significant major league track record – present a unique challenge for what is intended as a system for objectively evaluating players’ major league track records. As I’ve noted before, EWSL uses a standard arbitrary figure for all rookies – it does not distinguish between, say, Ryan Zimmerman and Reggie Abercrombie if both are expected to hold everyday jobs. I’d like to add a non-subjective adjustment for rookie quality, but until I can get Major League Equivalency Win Shares (I don’t believe they exist anywhere), I have to rely on the facts that (1) bad rookies rarely get everyday jobs and (2) good rookies often fall on their faces.
Of course, the one subjective element of this is my evaluation each spring of who looks like they have a job nailed down. One reason there were more rookies listed in 2006 was because I ran the EWSL rosters later in the year, mainly during April.
Anyway, part of the quest to make EWSL more empirical and less guesswork is that the adjustments – both the age adjustment and the rookie adjustment – get tweaked every year based on the accumulated data I have from, now, three years’ worth of results. Let’s look at those results:

Type of Player 2004 # 2004 WS 2005 # 2005 WS 2006 # 2006 WS # WS Rate
Everyday Players 6 74 10 101 17 187 33 362 10.97
Bench Players (Under Age 30) 4 26 10 38 11 29 25 93 3.72
Bench Players (Age 30+) 2 2 0 0 0 0 2 2 1
Rotation Starters 3 1 3 13 3 28 9 42 4.67
Relief Pitchers 4 21 1 1 6 43 11 65 5.91
TOTAL 19 124 24 153 37 287 80 564 7.05

After 2004, I had split off the rookie bench players by age because guys who break in as bench players in their 30s generally lack upside (the same isn’t true of starters, since rookie everyday players age 30 and up tend to be Japanese imports). You can see a steady uptick the last three years in the number of rookies being given jobs early in the season, although bearing in mind that part of that is changes in my own estimation of who would play. Still, there’s no disputing that last year had a real good crop of rookies from Day One. You can also see the miserable return from rookie starting pitchers – the good ones, like Jered Weaver and Dontrelle Willis, tend to come up a few months into the season, while with the exception of the occasional Verlander, guys who win rotation jobs early are often there more because of team need than because they are definitely ready.
I’ll be using these figures, rounded off (most are pretty close to whole numbers anyway) for this year’s adjustments – 11 for everyday players, 4 and 1 for bench players under and over 30, 5 for starting pitchers, 6 for relievers.