> **even after controlling for various factors such as career level, performance review scores and office location**
Did they also control for:
1) Willingness to suck up to the boss
2) Willingness to stay really late (something that is often not recorded officially at all)
3) Willingness to buy into the corporate culture
4) Continuous employment unbroken by time off for childbirth (that's actually quite a big one)
5) Willingness to bargain hard for pay, a trait that is significantly greater in men, or so the psychologists tell us.