The Mariners and Identity Theory

From a recent Jerry Dipoto interview, via Fangraphs:

Jerry Dipoto on the Mariners New Direction

“We see ourselves as a run-prevention club… Most teams have a run-prevention model, it’s a matter of how much they subscribe to it. Most of it is going to be predicated on ballpark. You’re much more likely to build a run-prevention model in a park like ours, or Dodger Stadium, or the Big A, than you would in say Baltimore. It’s a different model.”

And later: “Ground balls aren’t as critical to us as they would be to a normal team, because our ballpark absorbs fly balls a little better.”

The concept of a team requiring an “identity” of some sorts for themselves is common.

Equally common, and what’s truly underwriting the “identity” notion: the widespread idea that teams in hitters’ parks should build around hitters and teams in pitchers’ parks should build around pitchers.

Unfortunately, neither have a logical justification.

So you’re in a pitcher’s park, you load up on good pitchers… guess what? Because they’re above-average to begin with, they actually derive a smaller benefit (in R/9) from the ballpark than poor pitchers would. (That is, as long as one subscribes to the idea that park factors have a multiplicative—or any non-additive—impact, as pretty much everyone seems to agree).

However, the gap in Runs/PA between your (perhaps now neglected) offense and a league-average offense is actually shrunk by the park. The net effect, of course, is that it doesn’t matter. Regardless of one’s environment, there is no advantage to be gained from focusing particularly on either run scoring or run prevention.

Also, as to the notion that Safeco Field favors flyball pitchers…

Safeco HR/FB additive park factors, raw data by year:

A simple multi-year weighted average of the past 5 seasons yields a current factor of +.001, the same figure as a straight-line average of the past 3 seasons.

So it’s actually not even true that Safeco absorbs outfield fly balls better than the average park. Safeco reduces BABIP (-.004 BABIP PF), but not HR/FB. But even if it were true, it would be an extremely marginal factor. Enough to serve as a “tiebreaker” between two otherwise equal pitchers, but no more.

There’s an overriding moral here. Focusing on towards any identity other than “pursuing the best overall players” is a recipe for disaster.

Any “identity” concept or preference for a type/role over another will only be a limiting factor. Coors Field is possibly extreme enough to be an exception…. maybe. Otherwise, in the rare cases there’s some potential for asymmetry due to nuances of a park, the marginal differences are so tiny that the volume of players required to capture a meaningful residual benefit wouldn’t even exist in sufficient concentration to exploit it. To the degree an organization plans their roster towards an “identity,” they increase the chances it ultimately won’t be an identity they’d want.