The Negro Leagues Newly Incorporated into Major League Baseball: An Examination of Their Strength and an Evaluation of the Unification

1. introduction

In December 2020 Major League Baseball (MLB) acknowledged that seven of the Negro Leagues were, indeed, major leagues. The seven specific leagues and their active years are as follows:

1. 1. Negro National League I (NNLI) 1920– 31

2. 2. Eastern Colored League (ECL) 1923– 28

3. 3. American Negro League (ANL) 1929

4. 4. Negro Southern League (NSL) 1932 season

5. 5. Negro East- West League (NEWL) 1932

6. 6. Negro National League II (NNLII) 1933– 48

7. 7. Negro American League (NAL) 1937– 48

This study explores the strength of the Negro Leagues incorporated into MLB versus that of the National League (NL) and the American League (AL). To this end two methods are employed: (1) a statistical comparison of eleven seasons between the two sets of leagues and (2) an examination of one hundred and three specific games played between teams from the two sets of leagues. Though nonnumeric evidence is scrutinized the aforementioned points show that Negro Leagues were justifiably incorporated into MLB.

2. a multiyear statistical comparison of negro leagues versus the national league and the american league

Based on the idea of Puerzer (2020)¹ this section compares the overall records of the Negro Leagues that played between 1920 and 1948 to the National League (NL) and the American League (AL).^2,3 Statistics are pulled from eleven of the most significant seasons of Negro League Baseball between the years of 1920 and 1948. The years examined in the study are 1920, 1924, 1925, 1926, 1927, 1929, 1932, 1937, 1938, 1943, and 1947. The years 1920 and 1932 have significant data for them, so high- level “independent” teams are also included in the analyses.

2.1 Batting Statistics

Nineteen twenty- four is the first season explored without considering independent teams. The Seamheads website has statistics for 967 games played by teams in the Negro National League I (NNLI) and the Eastern Colored League (ECL), which is 39.3 percent of the total number of the 2,462 NL and AL games played that season. Following Puerzer (2020) the batting averages (BAs) of the players with at least forty plate appearances are first inspected. In the NNLI and ECL in 1924 there were a total of 217 such players while in the NL and AL the total was 328 players.⁴ For the 217 NNLI/ECL players the average BA was .262875, and the equivalent average for the NL/AL was .263649. The standard deviations (SDs), a measure of the spread of the data, of the two sets of BAs are 0.058566 and 0.057854, respectively. The t-distribution is used to compare the two BA averages. See the appendix for a short description of statistical tests and those used in this paper. Welch’s t-test results conclude that there is no significant difference (at a 10 percent level) between the two averages of BAs. Another way of thinking of the outcome is that if one decides that there is a difference between the two BA averages there is a greater than 10 percent chance of being wrong.⁵ Thus the conclusion is that there is no such difference. See tables 1 and 2 for the results for all years and tests performed for batting statistics.

To further compare the NNLI and ECL with the NL and AL the slugging percentages (SLGs) for the 217 and 328 players are investigated next. The averages of the two sets of SLGs are .353521 and .354217, respectively, whereas the two SDs are 0.108773 and 0.100458, respectively. As with the BAs, the outcome of Welch’s t-test shows there is no significant difference (at a 10 percent level) between the two averages of SLGs.

The t-distribution is not the only statistical test that can be utilized. A two- tailed Z-test can be employed to compare BAs because they are proportions. For this test, rather than the average of the 217 and 328 BAs, the test considers the total overall BA of each set of players. For the 217 players in the...