Chapter 8.3, Problem 20E

COST OF TAKING TIME OFF A survey was conducted of graduates of Harvard College 15 years after graduation. In the survey, the pay of graduates in different fields who had previously taken off 18 months, often to care for children, was compared with pay for graduates who had not taken time off. The average financial penalty for those who had taken time off is summarized in the following table:

Field	M.B.A	J.D.	PhD	B.A. only	M.D.	Others, Masters only
Penalty(%)	$-41$	$-29$	$-29$	$-25$	$-16$	$-13$

Find the mean of the financial penalty for the graduates who had taken time off. What is the standard deviation for these data?

Source: Claudia Golden and Lawrence Katz, Harvard College.