Her first book, "Family Dependence and Origins of the Welfare State", received critical acclaim in 1993.

While Pedersen comes to the job without administrative experience, Ellison is the current associate dean of the faculty.

He has been a professor since 1983 and was tenured seven years later.

Ellison has been highly involved in research, undergraduate education and graduate policy during his years at Harvard. For excellence in teaching undergraduates, he was named one the first five Harvard College Professors in April 1998.

A biological anthropologist by trade and a curator of human biology in the Peabody Museum, Ellison says his varied experience will help him in his new post.

"I think it is entirely compatible to be dedicated to undergraduate teaching, graduate education, research--all rolled into one," he said.

Lewis underlined Ellison's broad-based experience in discussing his qualifications, adding that he would "be a force for constructive thought in this time of change for graduate education."

Ellison's administrative experience has focused on restructuring graduate student financial aid, something which he hopes to emphasize in his new post.