I don't believe that study is well controlled. In fact, some of the claims are either contradictory or just don't make sense.
A 2009 study sponsored by the US Department of Labor, which analysed about 50 studies on the gender pay gap, concluded that "The differences in raw wages may be
almost entirely the result of the individual choices being made by both male and female workers."
There are observable differences in the attributes of men and women that account for most of the wage gap. Statistical analysis that includes those variables has produced results that collectively account for between 65.1 and 76.4 percent of a raw gender wage gap of 20.4 percent, and thereby leave an adjusted gender wage gap that is between 4.8 and 7.1 percent.[1]
A 2009 study sponsored by the US Department of Labor, which analysed about 50 studies on the gender pay gap, concluded that "The differences in raw wages may be almost entirely the result of the individual choices being made by both male and female workers."
There are observable differences in the attributes of men and women that account for most of the wage gap. Statistical analysis that includes those variables has produced results that collectively account for between 65.1 and 76.4 percent of a raw gender wage gap of 20.4 percent, and thereby leave an adjusted gender wage gap that is between 4.8 and 7.1 percent.[1]
http://www.consad.com/content/reports/Gender%20Wage%20Gap%20...