Eli Ginzberg, 91, an economist who taught at Columbia University for more than six decades, advised eight U.S. presidents and led pioneering research efforts in employment and health care, died Thursday at his home in New York City.

Dr. Ginzberg served as director of staff studies at the National Manpower Council from 1952 until 1961. He wrote about the importance of integrating women and racial minorities into the work force, and in the early 1950s he played a role in the desegregation of the Army as an aide to Secretary of the Army Frank Pace Jr.

Keith McCaw, 49, a billionaire whose family helped create a cellular-phone empire, was found dead Sunday in a hot tub in his lakeside Seattle mansion.

Police and firefighters received a 911 call of a possible drowning in the block where Mr. McCaw's mansion sits near Lake Washington. Paramedics tried to revive him, but he was pronounced dead at the scene. The cause was not immediately known.

Mr. McCaw made his fortune as a stockholder in McCaw Cellular Communications, which AT&T; bought in 1994 for $11.5 billion.