Saber-Slant #2: The Units of Baseball

Here’s a simple question for you: how do you measure the success of a team?

I don’t think anyone will have to stretch far to come up with answer for that question. Clearly, teams are generally measured by wins and losses. The best teams win the most games and move on to the playoffs. Fans are always cheering for their respective teams to win. Everyone involved with a team is looking to pick up wins.

Now, wins are the best unit of measurement, but how do teams get wins? Usually wins are accumulated by scoring and preventing runs. Indeed, a long time ago, a wise man named Bill James once found a formula that allows us to convert runs scored and allowed into wins. That means that runs and wins are generally interchangeable if you know the conversion rate.

Now we know that a team’s success is measured by runs and wins. So why wouldn’t we measure players in the same way?

It’s not that simple, or is it?

Here are the top five players in batting average in 2009, along with playing time information.

Joe Mauer: 606 PA, .365
Ichiro Suzuki: 678 PA, .352
Hanley Ramirez: 652 PA, .342
Derek Jeter: 716 PA, .334
Pablo Sandoval: 633 PA, .330

Just from that information, could you determine how much each player contributed offensively to their team’s wins? Probably not; even the least saber-inclined fans can tell that batting average alone is not sufficient to answer that question. I’ll add on a new number, OBP.

Mauer: 606 PA, .365/.444
Ichiro: 678 PA, .354/.386
Ramirez: 652 PA, .342/.410
Jeter: 716 PA, .334/.406
Sandoval: 633 PA, .330/.387

OK, now you have a better idea, but you still can’t answer the question. Let’s add an extra point of information, SLG.

Mauer: 606 PA, .365/.444/.587
Ichiro: 678 PA, .354/.386/.465
Ramirez: 652 PA, .342/.410/.543
Jeter: 716 PA, .334/.406/.465
Sandoval: 633 PA, .330/.387/.556

With this information, you may now have enough to tell how each player contributed to their team’s wins, and it may give an inkling about the relative rank of those players. But ultimately, this information cannot tell you how much each player contributed, because BA, OBP, and SLG are rate stats that have weights that do not ultimately relate to runs or wins.

Now, that doesn’t mean that those stats shouldn’t be used; the information described in a slash line tells a great deal about how a player produced, which is helpful for analysis as well. But how can we compare the relative weights of Ramirez’ .410 OBP versus Sandoval’s .556 SLG or Ichiro’s .354 BA? They are all contributing to the overall value of a player, but looking at these numbers gives us no way of comparison. The only way to compare them is to convert them to a common unit of measurement, runs or wins.

The same should be applied to everything you look at. A player’s stat line on offense, pitching, or even fielding should eventually be measured in runs or wins if comparisons are to be made. The value of an in-game strategy like a sacrifice bunt or an intentional walk should not only be logically described but also quantified to allow comparison of other available strategies. If the game can be measured in a common unit, we can start to analyze how decisions are made and players provide value to their teams. Next time, we’ll get into a little bit of how we credit runs and wins to players for their performances.

Tags: Derek Jeter, Hanley Ramirez, Ichiro Suzuki, Joe Mauer, Pablo Sandoval