Gianni Betti is Full Professor in Statistics and Economics at the Department of Economics and Statistics, University of Siena, Italy. He holds a PhD in Applied Statistics from the University of Florence, Italy. His research fields of interest and expertise include: personal income distribution theory and models; measures of living conditions with special reference to poverty analysis and inequality; equivalence scales and cost of children. Statistical methods for longitudinal (panel) analyses; nonresponse, interviewer effect, panel attrition and weighting problems; sampling theory with particular reference to small areas. He has worked on several projects for the United Nations, the World Bank and the European Commission and has been closely involved with the development of the EU Statistics on Income and Living Conditions.