This paper examines the role of secondary data-sets in empirical economic research, taking the field of income distribution as a case study. We illustrate problems faced by users of “secondary” statistics, showing how both cross-country comparisons and time-series analysis can depend sensitively on the choice of data. After describing the genealogy of secondary data-sets on income inequality, we consider the main methodological issues and discuss their implications for comparisons of income inequality across OECD countries and over time. The lessons to be drawn for the construction and use of secondary data-sets are summarized at the end of the paper.

The paper examines the identification of the "middle class" using data from LIS and LWS. It first considers definitions based purely on income, examining the rationale for different approaches and illustrating the implications for changes over time. It argues that the concept of "class" requires the examination of other dimensions beyond income. The paper considers the role of property and, drawing on the sociological literature, of occupations.

This paper examines different approaches to the measurement of multidimensional inequality and poverty. First, it outlines three aspects preliminary to any multidimensional study: the selection of the relevant dimensions; the indicators used to measure them; and the procedures for their weighting. It then considers the counting approach and the axiomatic treatment in poverty measurement. Finally, it reviews the axiomatic approach to inequality analysis. The paper provides a selective review of a rapidly growing theoretical literature with the twofold aim of highlighting areas for future research and offering some guidance on how to use multidimensional methods in empirical and policy-oriented applications.

Poverty is generally defined as income or expenditure insufficiency, but the economic condition of a household also depends on its real and financial asset holdings. This paper investigates measures of poverty that rely on indicators of household net worth. We review and assess two main approaches followed in the literature: income-net worth measures and assetpoverty. We provide fresh cross-national evidence based on data from the Luxembourg Wealth Study.

Consideration of world inequality should cause reexamination of the key concepts underlying the welfare approach to measuring income inequality and its relation to measuring poverty. This reexamination leads to exploration of a new measure that allows poverty and inequality to be considered in the same framework, incorporates different approaches to measuring inequality, and allows varied expressions of the cost of inequality. Applied to the world distribution of income for 1820-1992, the new measure provides different perspectives on the evolution of global inequality. JEL codes: D31, C80