Nielsen, the publicly traded media and marketing research giant whose shares are still controlled largely by big private equity firms, this morning shook up the composition of its board of directors and reduced it to 11 members, with one each from the private equity firms. The rest of the Nielsen board remains unchanged, and will be comprised of Nielsen CEO David Calhoun and four independent directors, though the private equity firms will still control the board. In a statement, Calhoun described it as a “natural progression” that would enable a “more efficient and streamlined” and “effective governance” of the company.The new board is comprised of: Michael S. Chae, The Blackstone GroupJames A. Attwood, Jr., The Carlyle GroupAlexander Navab, Kohlberg Kravis Roberts & Co.Richard J. Bressler, Thomas H. LeePatrick Healy, Hellman & FriedmanJames Marshall Kilts, Centerview Partners, Chairman of the Board of NielsenDavid L. Calhoun, CEO, NielsenKaren M. Hoguet, independent directorRobert C. Pozen, independent directorVivek Y. Ranadivé, independent directorJavier G. Teruel, independent director