As MLB nears the midway point, each division seems primed for an exciting summer. The largest first place lead currently stands at only five games in the loss column, and 19 teams sit within that margin (including division leaders). However, despite the top heavy concentration of teams, the overall level of parity is more diluted, especially when comparing individual divisions.
American League Win-Based Standard Deviation, 1901-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
Based on pro-rated standard deviation, the 2013 win distribution in the American League is narrower than in all but 25 other seasons in the junior circuit. This level of balance is particularly acute in the East, where each team is at least break-even and six losses separate last place from first. As of June 27, the A.L. East also boasted a win standard deviation of 2.7, which, even if approximately doubled to account for an equal outcome in the second half, would represent the closest race since the division was first formed in 1969.
American League East Win-Based Standard Deviation, 1969-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
American League Central Win-Based Standard Deviation, 1994-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
The A.L. Central is also in the midst of a very close race, with three teams within five losses of the division leading Tigers. Although most probably expect Detroit to pull away in the second half, if the trend holds, the Central’s win distribution would be the third narrowest since the three-division era began in 1994.
American League West Win-Based Standard Deviation, 1969-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
The Rangers and Athletics seem poised for another nail biting finish in the A.L. West, but behind those teams is growing separation. The Angels can’t be counted out of a second half surge, but should they continue to languish, the West could buck the A.L. trend of parity. On a pro-rated basis, the win distribution in the division currently ranks as the fifth widest since 1969, and the gulf could grow larger if also-rans like Seattle and Houston wilt even more in the summer.
National League Win-Based Standard Deviation, 1901-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
Unlike the junior circuit, the National League is not exhibiting a noteworthy level of competitive balance. With a pro-rated standard deviation nearly two wins higher than the A.L., the senior circuit’s 2013 parity level ranks 54th among 114 seasons. And yet, despite the overall separation in the league, the N.L. West could wind up being the wildest division of them all.
National League West Win-Based Standard Deviation, 1969-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
Only six losses currently separate the first place Diamondbacks and last place Dodgers, while the division’s win-based standard deviation is less than two. If first half outcomes are pro-rated over the rest of the season, the level of parity would be the highest in the history of the N.L. West, and rank behind only the 1987 and 1994 (only four teams) AL West races for the closest in baseball history (in both the League and Division eras).
National League Central Win-Based Standard Deviation, 1994-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
Although the N.L. Central could end up with an exciting three-team pennant race between the Pirates, Cardinals and Reds, the overall level of parity is weighed down by the struggles of the Brewers and Cubs. If extended over the season, the current win-based standard deviation would translate to a gap of nearly 15, representing the highest level of dispersion in the division’s existence.
National League East Win-Based Standard Deviation, 1969-2013
Note: 2013 is based on pro-rating current records over the course of a full season.
Source: Standings data from baseball-reference.com
In the N.L. East, the Braves currently enjoy the major’s largest lead, and only the Nationals seem to have a realistic chance of mounting a challenge. Throw in the likely hardships of the Mets and Marlins, and the N.L. East is also a good bet to post one of its least competitive seasons.
In some divisions, the amount of parity could be historic, and the number of team vying for a playoff slot could be unprecedented. That should make Bud Selig and baseball’s many TV partners very excited, especially if the glut of post season contenders leads to even more playoff games. Of course, that’s no consolation to the teams already playing out the string, but at the very least, the promise of several heated pennant races should give all baseball fans something to see in September.
Leave a Reply