Win Two Tickets to a SuperFreakonomics Lecture in New York

SuperFreakonomics is being published on Tuesday, October 20, and Levitt and Dubner will be popping up here and there to talk about it. (Here’s a fairly complete schedule.) Their first public lecture takes place at the exquisite Symphony Space in New York City on Wednesday, October 21, at 7:30 p.m. Tickets can be bought here, but you also have a chance to win a free pair. Just be the first person to correctly answer the following question:
What do Ignaz Semmelweis and Robert S. McNamara have in common? Your answer should include a cost component.
The answer, and the winner, will be revealed early next week. Good luck.
Addendum: We announce the winner here.