> Gender-based wage discrimination remains a problem today and a percentage of the wage discrepancy cannot be explained by non-discriminatory factors, said government and private experts ..
In http://www.huffingtonpost.com/christina-hoff-sommers/wage-ga... , in an essay that argues that illegal wage discrimination is minor, I read:
> What the 2009 Labor Department study showed was that when the proper controls are in place, the unexplained (adjusted) wage gap is somewhere between 4.8 and 7 cents. ... The AAUW notes that part of the new 6.6-cent wage-gap may be owed to women's supposedly inferior negotiating skills -- not unscrupulous employers. Furthermore, the AAUW's 6.6 cents includes some large legitimate wage differences masked by over-broad occupational categories. ... Could the gender wage gap turn out to be zero? Probably not. The AAUW correctly notes that there is still evidence of residual bias against women in the workplace. However, with the gap approaching a few cents, there is not a lot of room for discrimination.
If it's 2 cents, out of 23 cents, then that's 9%. While minor compared to indirect societal factors, I don't think it's small enough to dismiss outright.
Neither you nor I can explain the unexplained component. It's true that it may have nothing at all to do with discrimination on the basis of sex. However, that is very doubtful as we see successful lawsuits where there is wage discrimination based on sex and we see settlements for that accusation, so we know there it's still ongoing. And we know that mediated settlements are rare, so they are the tip of the iceberg.
Therefore, I see no reason to reject illegal wage discrimination as one of the factors that goes into the wage gap.