London, March 7--Professor Allyn Abbott Young, famous authority on economics and former head of the Department of Economics at Harvard, died here today of pneumonia at the age of 52.

Professor Young was one of the world's leading economists, an authority on markets, tariffs, distribution, obstacles to the free movement of trade, and export and import problems. He was head of the Department of Economics at Harvard until 1927, when he went to England to become professor of political economy in the University of London. At the time of his death, he held a prominent place at Geneva as president of the sub-committee on commerce and marketing problems of the preparatory committee, for the international economic conference of the League of Nations.

Took Ph.D. at Wisconsin

Born in Kenton, Ohio, in 1876, Professor Young graduated from Hiram College with the degree of Ph.B. in 1894, a member of the Phi Beta Kappa. Eight years later he was awarded the degree of Ph.D. by the University of Wisconsin.

His first teaching position was in the department of economics at Wisconsin. Leaving there, he taught successively at Western Reserve, Dartmouth, Leland Stanford, Washington University, Cornell, Harvard, and finally at the University of London.

Active During War

The World War found him director of the Bureau of Research of the War Trade Bureau, and in 1918 he was chief of the Division of Economics and Statistics of the American Commission to Negotiate Peace.

Secretary-treasurer of the American Economic Association, from 1914 to 1919, he was elected president in 1920. He was fellow of the Royal Statistical Society, a member of the American Academy of Arts and Sciences, a member of the American Statistical Association, a commander of the Order of the Crown of Belgium, and a member of the International Statistical Institute.

Professor Young was also the author of many well-known economical and statistical books and articles.