Wyers: The importance of a living replacement level

From SABR member Colin Wyers at Baseball Prospectus on September 19, 2013:

Last week, we talked about what replacement level is, and why we need it. Now let’s talk about who replacements are, and how to find them.

What we uncovered last time is that, rather than being some wholly arbitrary baseline concocted by evil sabermetric geniuses, replacement level (and the consequences of replacement level-based analysis) in fact grow out of something fundamental to the game: the distribution of talent in baseball, and the limited number of roster spots available. So the question becomes, how do we measure the distribution of talent? What are some things we need to make sure we’re capturing?

Sabermetrics is a field of inquiry open to just about anyone, and while the field is known for its own share of geniuses, occasionally one comes to it on loan from other fields. Stephen Jay Gould was a prominent paleontologist and evolutionary biologist, but he was also a passionate baseball fan. And Gould noticed something interesting, as recounted in his essay “Why No One Hits .400 Any More.”

When we contrast these numbers of the past and present, we encounter the well-known and curious phenomenon that inspired this article: great players of the past often stand further apart from their teammates. Consider only the principle measures of hitting and pitching: batting average and earned run average. No one has hit .400 since Ted Williams reached .406 nearly half a century ago in 1941, yet eight players exceeded .410 in the fifty years before then. Bob Gibson had an earned run average of 1.12 in 1968. Ten other pitchers have achieved a single season ERA below 1.30, but before Gibson we must go back a full fifty years to Walter Johnson’s 1.27 in 1918. Could the myths be true after all? Were the old guys really better? Are we heading toward entropic homogeneity and robotic sameness?

As Gould notes, it seems unlike that players of old really were better than players of now. “We live better, eat better, provide more opportunity across all social classes,” he said. “Moreover, the pool of potential recruits has increased fivefold in one hundred years by simple growth of the American population.” And baseball is no longer a wholly American game; Major League Baseball now can pull the best talent from across the world.

Read the full article here: http://www.baseballprospectus.com/article.php?articleid=21840

Originally published: September 19, 2013. Last Updated: September 19, 2013.