Alumni of Columbia have occupied top positions in Wall Street and the rest of the business world. Notable members of the Astor family attended Columbia, while other business graduates include investor Warren Buffett, former CEO of PBS and NBC Larry Grossman, chairman of Wal-Mart S. Robson Walton and Bain Capital Co-Managing Partner, Jonathan Lavine. CEO's of top Fortune 500 companies include James P. Gorman of Morgan Stanley, Robert J. Stevens of Lockheed Martin, Philippe Dauman of Viacom, Ursula Burns of Xerox, and Vikram Pandit of Citigroup. Notable labor organizer and women's educator Louise Leonard McLaren received her degree of Master of Arts from Columbia.