As a first approach to answering this question, compare the boxplots of salaries for each gender shown in Result 1. Result 1 was constructed using the Graphics > Boxplot option in StatCrunch with the salary column grouped by gender. A boxplot displays the 5number summary (minimum, first quartile, median, third quartile, maximum) for a data set. Clearly, the salaries for males tend to be much higher than those of females.

The summary statistics of the salaries for each gender are shown in Result 2. Result 2 was constructed using the Stat > Summary Stats > Columns option in StatCrunch with the salary column grouped by gender. Comparing the medians in Result 2, the typical male earns $54,471 while the typical female earns only $36,369. These values are represented by the lines within each box in Result 1.
Summary statistics for Salary:
Group by: Gender

One might initially think this is strong evidence that women are suffering from discrimination in terms of salary, but let's look a bit further. To understand the salary differences between the genders within the education field, consider the boxplots shown in Result 3. Result 3 was constructed in the same manner as Result 1 but with the where field set to Major = Education. Interestingly, we see that females tend to earn more than males in the education field.

The summary statistics in Result 4 bear this out even further with the median salary within education for females being $36,009 and the median salary for males within education being $32,001.50. The first quartile of female salaries (the left edge of the female box in Result 3) is even above the third quartile of male salaries (the right edge of the male box in Result 3) in the education field.
Summary statistics for Salary:
Where: Major = Education Group by: Gender

Likewise, to understand the salary differences between the genders within the engineering field, consider the boxplots shown in Result 5. Result 5 was constructed using the where field set to Major = Engineering with the boxplot option. Once again, we see that females tend to earn more than males in the engineering field.

The summary statistics in Result 6 bear this out even further with the median salary within engineering for females being $59,994 and the median salary for males within engineering being $55,019. As was the case with the education field, the first quartile of female salaries (the left edge of the female box in Result 5) is even above the third quartile of male salaries (the right edge of the male box in Result 5) in the engineering field.
Summary statistics for Salary:
Where: Major = Engineering Group by: Gender

At first glance, it might appear strange that overall females tend to earn less than males but within each major females tend to earn more than males. The reason for this is actually quite simple. Consider the two way cross classification shown in Result 7. Result 7 was constructed using the Stat > Tables > Contingency > with data option in StatCrunch. In this result, we see roughly the same number for each gender in the data (1088 females, 1144 males), but the large majority of females (856) were in the lower paying field of education while the large majority of males (924) were in the higher paying field of engineering. The fact that the genders are not equally distributed across major causes this paradox.
Contingency table results:
Rows: Gender Columns: Major

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