You don’t have to be a rocket scientist to understand the nuances of baseball…. But it helps!

I began my quest for an opportunity to analyze and write about baseball by doing the obvious: getting a degree in aerospace engineering from Princeton University and doing my senior research on annulled magentoplasmadynamic thrusters. After a glorious summer job of being an award-winning (just ask Daktronics) scoreboard programmer and operator for the Trenton Thunder in their inaugural season, I did the next logical step and went to the Massachusetts Institute of Technology to get a Ph.D. in Operations Research, a program of study that focuses on the practical application of statistics, probability and optimization theory for improved decision-making (hey, we’re getting closer).

The reason why I would make a great contestant on Baseball Prospectus Idol and the next great baseball analyst is that along with my passion for baseball (and the better understanding of it through quantitative analysis), my job with an elite operations consultancy has trained me on using the tools of operations research to find insights quickly in a mountain of a data and be able to present these insights in compelling ways.

On a personal note, I live with my wife and two-year old twin sons, north of Boston. Every day I struggle with the decision to raise my boys as Royals fans like their father (probably leading to daily playground pummeling) or accept the inevitable: they WILL become (gulp!) Red Sox fans.

Does Organizational Depth Really Matter?

Going into spring training 2009, the Kansas City Royals had nineteen of the twenty-five roster spots set. Over the next six weeks, dozens of threads and thousands of posts on the Royals’ chat boards discussed the eleven remaining candidates for the last six spots. As the April 5th roster deadline approached, name-calling and hurt feelings increased exponentially. Similar verbal assaults were being hurled on the message boards for the other 29 teams as well. As I watched this, and sometimes entered the fray, I wondered: do these seemingly minor decisions really make a difference, given that the five “losers” of the Opening Day roster sweepstakes will likely contribute significant time anyway?

I looked at the amount of playing time (measured by plate appearances for position players and innings pitched for pitchers) of each team in 2008 to determine what kind of organizational depth is needed by a typical major league team. Further, I used VORP to determine the value of organizational depth to the team’s performance. To focus how organizational depth affects championships, I categorized teams into one of three buckets: playoff teams, teams that were above .500 but missed the playoffs (contenders), and below .500 teams (second division)

On average, 46.1 players (22.9 pitchers and 23.2 position players) stepped on the field for each major league team, the low being the White Sox with 39 players, the high being the injury-riddled Padres with 59 different players. Playoff teams used 43.1 players, contenders used 44.7 players, and second division teams used 48.8 players.

As a next step, I labeled if the player was on the Opening Day roster, making a few subjective adjustments for an “Effective Opening Day Roster” which is what the organization would likely have had if everyone was healthy. For example, I would assume that had they not been disabled list, John Lackey and Josh Beckett would have been on the Opening Day roster for the Angels and Red Sox, respectively.

Position Player Depth

For position players, I categorized the top (measured by Plate Appearances) nine players that could effectively fill out the lineup card as starters (for the NL the ninth player is considered main pinch-hitter), and the remainder as bench players. Next I labeled the next four players (who were within the organization as of Opening Day) as the first tier of replacements, assuming that many of these players “just missed” being on the roster. All other players that saw game action were labeled as fillers.

            Playoff Team      Contender Team  Second Divison Team
              PAs/VORP          PAs/VORP         PAs/VORP
Starters    4,598/189.0       4,376/190.4      4,243/141.8
Bench         806/  9.4         727/ -4.7        538/ -4.1
Replacements  546/ 15.7         679/ 11.1        776/  8.8
Filler        127/  1.9         138/ -2.0        340/ -4.8
Total       6,077/216.0        5921/194.7      5,897/141.7

The key insight is that organizational depth does seem to be a driver between playing in October and just being a contender. The VORP of starters of playoff teams versus contenders is essentially the same (189.0 vs. 190.4). However, the extra 20+ VORP is from the organizational depth, mostly coming from the bench players. For second division teams, simply not having the horses in the starting lineup is causing their separation with the .500 barrier.

Another thing that pops out of the data is that the better the team, the fewer plate appearances for first-tier replacement players and smaller difference in VORP between the Opening Day bench players and first-tier replacement players. Is this because a lack of injuries, or is it because the front office made the right decision at the beginning of the year?

Starting Pitching Depth

For only a few organizations is the five-man rotation set in stone at the beginning of Spring Training. For some organization, even the #3 slot is uncertain. As we will see, for the teams where even the #3 slot is uncertain, this suggests that their players should start booking their October fishing trips early.

For the average organization, only 120 of a team’s 162 starts are usually going to be pitched by the five designated starters from Opening Day. A few notable exceptions in 2008 were the White Sox and the Rays – both playoff teams – where their starting five started 153 games for both teams. Almost half the teams (14) used a #9 starter. The average team in 2008 had their starts allocated as follows:

Depth Chart Position       Games Started
Opening Day 5-man rotation   120
#6 starter                    15
#7 starter                     9
#8 starter                     6
#9 starter                     3
#10 starter                    3
Swing men in bullpen           6

Laying out the VORP of each rotation spot shows where playoff teams separate themselves from the rest of the pack.

Starting        Playoff    Contender   Second Division
Rotation Spot   Team VORP  Team VORP    Team VORP
 1                50.9       49.1        32.5
 2                31.5       29.8        23.1
 3                27.7       16.9         1.3
 4                21.2       15.2         0.4
 5                11.3        5.6        -1.1
 6                15.0        3.5         7.8
Total            157.5      120.2        63.9

As we would expect, a playoff teams has better quality at every starting position in the rotation. However, when compared to the contenders, the #1 and #2 slots are almost identical in quality. The separation begins to occur at the #3 slot, and continues through the rest of the depth chart. Specifically, the 37.3 VORP difference between playoff teams and contenders is only 3.5 in the #1 and #2 slots, but 33.8 in slots #3 to #6.

The data suggests that second division teams have a typical #2 starter as their staff ace and another #2 or #3 for their second rotation slot, then essentially replacement-level pitchers from #3 to #5. The Royals 2008 starting rotation being a perfect example of this: staff ace Gil Meche (really a #2), Greinke (an emerging #2) and then the significant drop-off to Bannister, Bale, and Tomko. An interesting note is the significantly higher value that the #6 starter has than the #3 starter for second division teams. This likely signifies either health issues or organizational frustration at the lack of effectiveness of the back end, which is “solved” by the up and coming prospect that is forced into the starting rotation (see Armando Galarraga or Greg Smith)

Reliever Depth

In 2008, all 30 major league teams used at least 11 relievers. Typically, a team’s workhorse reliever averaged 82.5 innings (with an occasional start or two in there) and the 11th reliever averaged about 20.2 innings pitched. Roughly half of the teams used 15 relievers, with the extreme outlier being the Padres who used 20 relievers in 2008.

I divided relievers into 4 groups: top 4 relievers as measured by innings pitched (Group 1 – top relievers) on the Opening Day roster, the remaining relievers on the Opening Day roster (Group 2 – bottom relievers), the 4 relievers with the most innings pitched not on Opening Day roster (Group 3 – first-tier replacements) and all other relievers (Group 4 – the fillers):

Reliever Group  2008 Playoff Team  2008 Contender  2008 Second Division
                   IP/VORP            IP/VORP         IP/VORP
Group 1         279.0/67.1         264.2/51.7      258.0/37.1
Group 2         115.0/12.5          95.1/ 6.0       83.1/ 0.0
Group 3          71.1/ 4.0         104.2/12.1      140.1/21.8
Group 4           8.1/ 0.1          27.2/-0.5       49.2/-6.4
Total           473.2/83.6         492.1/69.1      531.1/53.6

The data suggests that the front line players (starters and front end of the rotation) for playoff teams and contending teams are nearly identical. However, the Opening Day bullpen of a playoff team is much better at every position than the contender’s bullpen. The relatively large VORP and slightly higher innings pitched of the Group 3 relievers (first-tier replacements) suggests that many of the contending teams are still trying to find the right relievers throughout the season. Similar to the position players, there’s an uncertain cause-and-effect relationship regarding the lack of usage of first-tier replacement relievers. Is this because the playoff teams are lucky and don’t need to use as much depth because of fewer injuries, or has the team identified the right players in spring training so that they don’t need to make changes due to ineffectiveness.

Putting it all together

Just comparing playoff teams to the contenders, the organizational depth looks like:

                         Playoff Teams  Contenders  Difference
Starters 	                  189.0        190.4       -1.4
All Other Position Players         27.0          3.7      +23.3
Starting Rotation - Front End      82.4         78.9       +3.5
Starting Rotation - Back End       75.1         41.3      +33.8
Opening Day Relievers              79.6         57.7      +21.9
Organizational Depth Relievers      4.1         11.6       -7.5
Overall                           457.2        383.6      +73.6

So going back to the original question, do the initial decisions of the front office in setting the Opening Day roster really make a difference? On one hand, there’s no question that the losers of the Opening Day sweepstakes will likely see significant playing time, however, the data suggests that maybe the better teams are the ones that get the decision right the first time.