One of the most often cited criticisms of WAR is that replacement level is essentially an arbitrary construct, making the entire model just an act of theoretical speculation. The idea of replacement level is to essentially set a baseline for expected performance from a team that invested the absolute minimum in putting together a Major League roster. This replacement level team wouldn’t have a farm system, so that they didn’t have to spend money on draft picks, coaches, equipment, or facilities. They would rely entirely on league minimum veterans to build out their roster, thus allowing us to see how approximately many wins a team could expect if they did the absolute bare minimum in terms of organizational investment.
That team doesn’t exist, obviously, as even organizations that completely tear down their big league roster work to rebuild through accumulation of young talent, and no team actually spends the league minimum on its Major League payroll. Thus, the criticism that the entire exercise is a thought experiment, not applicable to the Major Leagues and incapable of serving as a baseline against which Major League players should be judged.
However, that argument misses out on the fact that MLB teams give us a pretty great list of replacement level players every winter, thanks to the processes of minor league free agency and the waiver system.
Minor League free agents are the quintessential idea of a replacement level player. For the most part, they simply want a job in the big leagues, and they don’t have enough leverage to be picky about what kind of job it is. They take non-guaranteed invites to spring training in hopes of earning a spot on the roster, and if they don’t play well in March, they end up in the PCL or the International League, waiting for an injury to create a need that will get them back to the big leagues for a little while.
If a Major League team was attempting to build out a roster of league minimum players, these are exactly the kinds of talents they’d be picking from. However, they could also supplement those players with waiver claims, as there is a second pool of replacement level talents available to any team willing to simply use a 40 man roster spot to obtain a player who doesn’t have a say in where he lands. This winter, we saw a number of players — Scott Cousins, Russ Canzler, and Sandy Rosario among the most notable — change teams multiple times, as GMs tried to sneak them through waivers so they could be stashed in Triple-A without requiring a spot on the 40 man roster. Since they wouldn’t require more than a league minimum salary and the price of a waiver claim is so low that it doesn’t materially affect a team’s budget, we’ll include these players in the pool of replacement level talents as well.
Using the Transaction Tracker from MLBTradeRumors, I went through and identified two dozen position players who signed minor league contracts or were repeatedly claimed on waivers this winter, with the sole requirement being that they had at least 100 combined plate appearances between the last two seasons. Okay, I actually only identified 23 such players, but Jeremy Hermida had 93 plate appearances, and two dozen sounds better, so I included him in order to get the list up to 24. Since I did this manually, I’m sure there are a few guys I missed, but as you’ll see, it’s not going to change the conclusion in any meaningful way – these 24 guys a pretty good representative sample of what a replacement level Major Leaguer looks like.
To combat selection bias, we don’t want to just focus on what these players did last year, as the fact that we’re identifying players who were forced to sign minor league deals means that we’re starting with a group that likely underachieved last year. A replacement level player who overperformed in 2012 likely secured his place on a 40 man roster for the winter, removing him from the pool of players available to sign minor league deals or get passed through waivers. So, we need to adjust for the fact that the 2012 performances are likely a bit below their actual talent levels, and we can simply adjust by looking at a larger pool of data. We don’t want to go back too far, of course, as many of these guys are aging players who aren’t what they used to be, so to try and come up with a balance of a larger but still relevant sample, we’ll simply focus on how these 24 players did over the last two years.
In the past two years, these 24 players have combined for over 10,000 plate appearances in the Major Leagues, and they’ve combined for -0.7 WAR. If you scale that back to a rate of per 600 plate appearances, that’s -0.04 WAR per full season. For a “theoretical” construct that supposedly doesn’t reflect reality, replacement level seems to do okay.
For those interested, here’s a list of the 24 players, and their 2011-2012 performance. If someone asks you what a replacement level player looks like, point to one of these guys.