T. Nicolaus Tideman (//, not //; born August 11, 1943 in Chicago, Illinois) is a Professor of Economics at Virginia Polytechnic Institute and State University. He received his Bachelor of Arts in economics and mathematics from Reed College in 1965 and his PhD in economics from the University of Chicago in 1969. Tideman was an Assistant Professor of Economics at Harvard University from 1969-1973, during which time from 1970-1971 he was a Senior Staff Economist for the President's Council of Economic Advisors. Since 1973 he has been at Virginia Tech, with various visiting positions at Harvard's Kennedy School of Government (1979-1980), University of Buckingham (1985-1986), and the American Institute for Economic Research (1999-2000).
Tideman's academic interests include taxation of land, voting theory, and political philosophy. In 1987, he devised the voting system called ranked pairs, which is a Condorcet method, and in 2000 the CPO-STV proportional voting method. Tideman also devised the independence of clones criterion which both of his methods satisfy. He is an associate of the Earth Rights Institute. His book Collective Decisions and Voting: The Potential for Public Choice was published by Ashgate Publishing in November 2006.