Baseball is measured at its most fundamental level by runs and outs.
Obviously, runs are the key to winning a baseball game, whether that comes in the form of scoring them or preventing them. The most runs win the game.
However, outs can be considered the “currency” of the game. Teams exchange outs for runs during the course of the game. Each team has 27 outs per game in which to score as many runs as possible.
Similarly to a company’s operation, you don’t want one of your employees overspending or wasting money without producing a lot of value for the company. To point out the blatant analogue, a baseball team doesn’t want players wasting outs without providing a lot of runs.
This ties into the OPS concept well, as OBP shows the rate at which a player consumes outs (so a .400 OBP guy consumes an out 60% of the time) while simultaneously creating a run-scoring opportunity, while SLG shows a player’s ability to produce runs by advancing runners along the basepaths.
But here’s the tricky part. I say I have Alfonso Soriano batting an .850 OPS and Aramis Ramirez around .900 and Ryan Theriot has an OBP of .382 and Derrek Lee is batting .320 but Mike Fontenot is struggling to break the Mendoza Line. Good offensive numbers, in general, right?
Ok, so what does that mean? How many runs do these players provide for my team? How effectively does my team use its outs toward winning a game?
This is where Value comes in to play.
Join me after the jump
Keith Woolner of Baseball Prospectus developed the Value Over Replacement Player, or VORP, as an analysis of how many runs a player will provide his team over the course of a season.
Now there’s one key distinction to make here: A “Run” in the scorekeeper’s batting line is NOT the same as a Run in terms of value. A Run (and by extension, an RBI) is a function of a team’s lineup, in that a Run isn’t a Run without an RBI (with some small exceptions) and an RBI isn’t an RBI without a runner to drive in. I’m obviously excluding Home Runs from this. Point being, forget what you knew about Runs before this.
Now, VORP centers around the concept of the Replacement Player. Typically, replacement level players are average defensively, and below average offensively, typical about 80% of league average. Think Omar Quintanilla. The basis of this concept is there’s a plethora of guys who can play at this level between AAA and Free Agency who can be acquired freely. You want to have a team full of guys better than that. The caveat here is that Replacement level is different for Catchers and 1B/DH. Because of the defensive importance of the Catcher position and the relatively Unimportance of the 1B/DH positions, Replacement Level is set lower for catchers and higher for 1B.
Now, there are many ways of calculating the number of runs a player adds over the season. You could use Bill James’ Runs Created, Base Runs, Equivalent Runs, etc etc. You can find many of these by a simple Google search. The key to this analysis is to pick a particular run formula and stick with it. I’d advise one of the more complicated ones, because then you can use a spreadsheet and be a big dork, but more importantly, so you can get an accurate look at a batter’s complete game. Take a look at the Wikipedia article on Runs Created.
It should be noted that there is a VORP for pitchers as well, we're not covering it in this article.
Now that we have offensive production just in terms of runs, what comes next?
Baseball is a zero-sum game, meaning that for any team to win, another must lose. That said, it’s just as good to score a run as it is to prevent a run. So while a player’s fielding doesn’t contribute to their offensive numbers, it certainly counts for the player’s overall production (more on that in a minute).
Now, I prefer to use UZR (Ultimate Zone Rating) for my fielding metrics, which I can easily find at Fangraphs, because it’s already in terms of runs prevented. Also available are the FRAR (Fielding Runs Above Replacement) numbers from Baseball Prospectus, which are also in terms of runs.
So this all builds to something, and that something is Wins.
Wins Above Replacement Player, or WARP, is the amount of wins a player will contribute to a team over the course of a season. A good rule of thumb for transforming runs into wins is that 10 runs ~ 1 win. Granted, 1 run in Coors is not worth 1 run in PetCo, but for the sense of basic evaluation, 10 runs does the trick just fine.
The concept behind WARP is that a player will add that many wins to his team’s total beyond that which a replacement player would add. You also have to remember that by inserting a 5-win player onto your team, you subtract the wins that the player he is replacing would provide.
So now that we’ve established what VORP and WARP are, how do we use them? Well, VORP and WARP are both counting stats. You play more, you create more runs for your team, and by extension, more wins. You use VORP/WARP to look back on a body of work and say “Oh that’s pretty good” or “well that’s poor”.
We have an idea of how to value players now based on a body of work. This is good to use when determining nice big blanket statements like “Best” and “Worst” and “MVP”. It’s another big number put in with the intent of finding an “All-Encompassing” statistic, and while it may have its faults still, it’s another step in the right direction.