3.2.3 Exploration 3B: Gender Discrimination Analysis with Pivot Tables
To help understand how pivot tables work and can help you analyze data to explore a problem
context, we will consider a small private company called EnPact that produces environmental
impact statements. (Basically, when a company wants to build in an area or manufacture a
product, impact statements help predict the expected impact of this work on the local ecology.)
Recently, the company has been sued by a group of female employees on the grounds that
males have an unfair advantage in the salary process. By exploring this problem using
pivot tables, you will learn a fundamental truth about data mining: the deeper you
explore, the more you are forced to reconsider each and every piece of evidence you
have.
The company salary data (and employee profiles) are in the file C03 EnPact.xls [.rda]. Open
this file. Using simple pivot tables (see the How To Guide for this section), answer the following
questions.
- How many male employees are there? How many female employees? What percentage
of the employees is male? Female?
- What is the average male salary? What is the average female salary?
- Based on your answers to #1 and #2, write a sentence or two discussing the company’s
lawsuit.
- Cross-section the data by both Gender and Education Level. Look at the average
salaries of the employees and discuss the company’s lawsuit.
- Cross-section the data by both Gender and Job Level. What does the lawsuit look like
now?
- For a final look at just how complex this issue is, cross-section on three variables
simultaneously. Set the pivot table up with Gender as the row variable, Education
Level as the column variable, Job Level as the ”page variable” (at the top of the pivot
table) and average salary as the data.
- Using the three-variable pivot table, pull down the ”Job Level” menu and look at each
job level separately in the pivot table. Are there any particular job levels where the
male and female salaries, after accounting for education, are roughly the same? Are
there any where the salaries are quite different?
- Select one of the job levels that shows a large difference in salaries by gender. Go back
to the original data. Can you account for these differences by looking at the numerical
variables (Years of experience and Years Prior)?