Some time back, I used 2014 FanGraphs Wins Above Replacement (fWAR) to make 2015 projections. It's a dangerous notion to just add up WAR values and make grand pronouncements, but it's a reasonable starting point for evaluating changes teams made to address their needs.
That post only looked at offense and pitching, and this one focuses on team defense. One thing that the advance in baseball analysis has revealed is that, while defense is important, to place it on an equal footing with offense and pitching is to overemphasize it. One way to explain this is that a player can score four runs with one swing of the bat if the bases are loaded, whereas it's far less common to allow four unearned runs to score with one miss with the glove. This is best understood by realizing that of the 19,761 runs scored in 2014, only 1,654 were unearned, less than ten percent. In other words, poor fielding led to runs allowed less than ten percent of the time, as opposed to good offense over ninety percent. With that kind of imbalance, it's hard for teams to ride defense to a World Series championship.
By the same token, just throwing anyone out in the field with the expectation that their offensive contributions with the bat will outweigh any fielding deficiencies is also overly simplistic. As baseball continues the trend in declining offense, defense takes on a greater role as run prevention gains in importance.
August Fagerstrom did a similar review at FanGraphs last week, but I'll be using a Tableau data viz to illustrate team defense using projected starting lineups as defined by the depth charts at mlb.com:
There are three tabs, with the primary one using a measure I had to create, Defensive Runs Saved per 150 games (DRS/150). DRS gives a measure to defense, something baseball has been seeking to since its inception, and while I would prefer to use UZR/150, it doesn't exist for pitchers or catchers. In addition, using DRS by itself is unfair since it's a counting stat, so normalizing it to 150 games helps correct vagaries in playing time. If interested, the second tab shows DRS by itself and the third UZR/150 for those positions with measures.
The numbers shown are for 2014 only. I toyed with going further back and can't fully explain why I changed my mind, but I chose 2014 and that's that. The DRS/150 tab shows the cumulative value for all positions, the starting rotation and closer, a total of 14 different players for each team. Scrolling over the points shows information for individual players, and despite how the bars look, the chart is sorted best to worst, with the Cardinals (by a fairly healthy margin) the best projected defensive lineup, and the Cubs the worst. Should you wish to see all players projected to make the team, change the Starter filter from 1 to Null, but understand this will show more than 25 players.
There are some oddities in the data. In all cases, I used the measure for the position the player is projected to play. The best example is Ryan Zimmerman of the Nationals, their third baseman last year until going down with an injury and watching Anthony Rendon take his place. The Nationals, with the loss of Adam LaRoche and his stunning beard to the White Sox, shifted Zimmerman to first, where he played 18 innings in 2014 with a DRS of -1, leading to a DRS/150 of -75 and a UZR/150 of -109.1. It's reasonably safe to state that he won't be this bad--if he could play third (and he could), he can probably handle first. This is the danger of small sample sizes, but that's why projections are tempered with common sense and used for what they are--reasonable, but not perfect, representations of what can be expected based on past performance.
Pedro Alvarez made a similar shift from third to first after the emergence of Josh Harrison for the Pirates in 2014, which was probably aided by his league-leading 25 errors. His limited amount of playing time at first is why he's not on the chart, since he had 0 DRS in the 37 innings he played there last year.
There are a couple of other anomalies--for example, I project Kris Bryant will be the third baseman for the Cubs by the middle of April, Micah Johnson the White Sox second baseman, and mlb.com depth charts have rookies for other teams, players with no DRS to factor in. There probably aren't more than five or six of these players as I recall, but it's almost certain their defense won't be neutral. There's also some position shifts, such as Yunel Escobar projected at second base for the Nationals even though he hasn't played second since his rookie season, and in these cases I used their 2014 DRS for their primary position. Generally speaking, it's not often players move from an easier to more difficult position, and in Escobar's case, a former shortstop should be able to handle second.
This post came about because I was going to explain how Dexter Fowler of the Cubs would be a better center fielder in Wrigley Field than he was in Colorado or Houston, but after looking at his defensive numbers realized it would be almost impossible for him not to be, since he was among the worst defensive center fielders since coming to the majors in 2008 (min 1000 innings). While I think he will be better in Wrigley (go to the Park Overlays feature at the ESPN Home Run Tracker, enter Coors Field as the primary ballpark, Wrigley Field as the overlay and see for yourself how much less ground he'll have to cover in left-center), he'll be part of a team that could be defensively challenged at every position except first and right field. Defense doesn't win championships, but bad defense doesn't help any either.
Play around with the data viz to see how players at the different positions rate, or filter to see how teams look up the middle (choosing catcher, second, short and center field), pitching staffs, outfields or however desired. If I get bored and there's enough interest in this post, I may recalculate everything using more years of data (FanGraphs makes it very easy to grab huge chunks of it at a time, but DRS and UZR/150 data only go back to 2002), and while a larger number of years is a better way to view defense, there are rarely wild swings--for example, players rarely go from Gold Glove to glove-optional in the course of a year.
Adding the sum of the parts ignores the understanding that defense is a team event in that everything from pitch selection, shifting and proper positioning go into successful execution. Sometimes a defender is right where he needs to be but the ball just doesn't go where it's supposed to go, which is the difference between probability and individual events. The harder runs are to score, the more important it is to keep them from being scored, and the data viz shows which teams could be in the best position to make this happen in 2015.
All data from FanGraphs, and any mistakes in processing it are the author's.
Scott Lindholm lives in Davenport, IA. Follow him on Twitter @ScottLindholm.