Prasanta K. Pattanaik is Emeritus Professor at the University of California, Riverside (US). He did his Ph.D. (1968) at the Delhi School of Economics, University of Delhi (India). He has done research on the theory of social choice and welfare economics, decision theory, trade theory, and the measurement of living standards and deprivation. Pattanaik’s publications include papers in various professional journals, three books, and several co-edited volumes. He is a Fellow of the Econometric Society and was President of the Society for Social Choice and Welfare (2006-2007). He is a series editor of the Springer series Studies in Choice and Welfare. Yongsheng Xu is Professor of Economics at the Andrew Young School of Policy Studies at Georgia State University (US). Xu received his PhD in economics at Tulane University (US). Xu’s research and teaching interests include microeconomic theory, particularly individual and collective choice theory, welfare economics, and information and organization. His current work focuses on the measurement of well-being and deprivation, dynamic choice and the performance of the market system. He has published numerous articles in such journals as Economic Theory, Economica, Economics and Philosophy, Games and Economic Behavior, International Tax and Public Finance, Journal of Economic Inequality, Journal of Economic Literature, Journal of Economic Theory, Journal of Risk and Uncertainty, Oxford Economic Paper, PLOS ONE, Review of Income and Wealth, Theory and Decision, and Social Choice and Welfare.