EL SEGUNDO, Calif. — Mattel has announced that Robert A. Eckert, 57, will retire as CEO, after 11 years with the company, effective Dec. 31. The board of directors has named Bryan G. Stockton, 58, who has held the position of chief operating officer for the last year, to succeed Eckert as CEO, effective Jan. 1, 2012. Eckert has agreed to continue in his role as chairman of the board, and the board has elected Stockton as a member of the board, effective January 1, 2012.