Well it isn't discrimination anymore. I didn't read that part; I accept their conclusions. They have three conclusions: girls like people, boys like things; females are under-represented in the high end of the ability distribution; and women want to start families when they should shoot for tenure track.
Now I dont by any of it, except that discrimination is gone. I think that a lot of it is educational issues. There is a huge amount of incompetence in math education. Elementary teachers that cant do arithmetic. (My older daughter took classes with them at UCLA and my GF taught them at Ohio State.) The daughter took a calculus class from a teacher that couldnt even pronounce the terms. "Derogatives" indeed. Possible role models that disparage math. Maybe boys persevere through this because of natural ability and interest but we could do better by all kids.
I also wonder if the engineering/physical sciences math track is doing a disservice to a lot of students. I never used calculus except to teach it to my kids. But there is lots of interesting and useful math out there that a lot of kids dont get to. Even calculus is interesting if bypass the rote.
