The Women in My Courses Will Earn 63% of the Men. Fair?

A new study shows that Canadian women with post secondary education earn only 63 percent of what men with similar qualifications earn.  Here is the Globe and Mail story. For the women in my class, look around.  Are the men here worth more than you?  Consider too that women outperform men in university, by 18%!  What can explain this apparent discrepancy between qualifications and performance and earnings?

The report shows that Canadian women posted better academic achievements than men at all levels – in high school, women have a graduation rate 8 per cent higher than men, which rises to 11 per cent for college programs and 18 per cent for university degrees. However, women with a postsecondary education still earned on average just 63 per cent of the salary of similarly educated men, up only slightly from 61 per cent in 1998. The number is identical for women with only a high-school education.

The gender pay gap is a topic of great debate. I’ve noted studies before.  Human rights and pay equity legislation in Canada seeks to address the gap by targeting gender discrimination.  It assumes that a major cause of the pay gap is overt or systemic discrimination by employers in pay and employment practices, and that laws can overcome that discrimination.  See, for example, the resources at the Equal Pay Coalition website and this nice overview paper by Toronto lawyer Mary Cornish. However, despite many of years of legislative initiatives, a large pay gap remains.
Others argue that women are paid less because their productivity justified a lower pay.  The argument is that women (1) chose careers that pay less (they are nurses and social workers rather than engineers and miners); (2) they work fewer hours than men because they have greater family responsibilities; and (3) they experience greater career interruptions due to childbirth and care, and this slows their income trajectory.  I noted in an earlier post that women who have children earn less than childless women. Here is a series of short You-Tube videos of a talk by speaker Warren Farrel who writes books arguing that women earn less for the three reasons I just listed.  He also argues that women have more rounded and balanced lives than men, but that this comes at a cost in terms of employment earnings.   He believes, therefore, that legal rules that try to eliminate the pay gap are wrong-headed and doomed to fail.
Do you think that pay gap is a social problem that the state should be trying to address through legal regulation?