Andrew E. Clark is a CNRS Research Professor at the Paris School of Economics (PSE). He previously held posts at Dartmouth, Essex, CEPREMAP, DELTA, the OECD, and the University of Orléans. His work has largely focussed on the interface between psychology, sociology and economics; in particular, using job and life satisfaction scores, and other psychological indices, as proxy measures of utility. The broad area is social interactions and social learning. Professor Clark is a member of the Editorial Boards of: Journal of Happiness Studies, Revue d'Economie Politique, British Journal of Industrial Relations, Review of Income and Wealth, Applied Economic Perspectives and Policy, International Review of Economics, Italian Economic Review, Evidence-based HRM, and the International Journal of Happiness and Development. Claudia Senik is Professor at the University Paris-Sorbonne and at the Paris School of Economics. She is also member of the IZA. Her main research interest is in the Economics of Happiness. A large part of her work focuses on the relationship between income, income distribution and subjective wellbeing. She frequently appeals to a comparative approach, based on the different environments in Western versus Eastern Europe. She is in charge of several international scientific cooperation programs related to her field of research. Professor Senik is a member of the editorial board of the International Journal of Wellbeing, Associate Editor of the IZA Journal of Labor Economics, and a member of the Editorial Review Board of Applied Research in Quality of Life. See her personal webpage: http://www.parisschoolofeconomics.eu/fr/senik-claudia/