Ansley Johnson Coale

Ansley Johnson Coale, a demographer and former director of the Office of Population Research at Princeton University, died Nov. 5 in Newtown, Pa. He was 84.

Dr. Coale was an internationally recognized expert on population trends and the demographic statistics that document them. He directed the population center, an adjunct of the Woodrow Wilson School of Public and International Affairs, from 1959 to 1976.

He introduced techniques that overcame some long-standing uncertainties that arose from estimates based on raw data. The new methodology helped in gauging such factors as mortality and fertility in populations for which only inaccurate or incomplete numbers are available.

In collaboration with William Brass, he refined the techniques in the book " Methods of Estimating Basic Demographic Measures from Incomplete Data " (written with Paul Demeny, 1967).

Dr. Coale ' s first influential publication was " Population Growth and Economic Development in Low-Income Countries " (with Edgar Hoover, 1958). That was followed by " Regional Model Life Tables and Stable Populations " (with Demeny, 1966).

Dr. Coale, a native of Baltimore, received his entire higher education at Princeton, graduating in 1939 in economics, earning his master ' s in 1941 and, after wartime service in the Navy, receiving a doctorate in 1947, the year he joined the faculty.

He was the author of scores of articles on various demographic topics and helped write additional textbooks on the growth and structure of human populations, fertility in Russia and the decline of fertility in Europe.

At the time of his death, he was a professor emeritus of economics and the emeritus William Church professor of public affairs.

President Kennedy appointed Dr. Coale in 1961 to represent the United States on the Population Commission of the U.N. Economic and Social Council, which he did until 1967.

Dr. Coale was also a past chairman of the committee on population and demography of the National Academy of Sciences and a member of the American Academy of Arts and Sciences and the American Philosophical Society, which published his autobiography in 2000. He was a past president of the International Population Union.

Dr. Coale is survived by his wife of 61 years, Sarah Campbell Coale; two sons, Ansley Jr. and Robert C.; and three grandchildren.