2 - Conceptual and measurement issues

Summary

The range of issues

In this chapter we consider some of the important issues that arise when one looks at child poverty from a dynamic perspective. Although some are the same as those relevant to measuring poverty at a single point in time, they often need to be seen in a new light when one looks at poverty longitudinally. We also draw attention to additional matters which arise from a focus on children.

Choosing the concept of living standards and the definition of poverty is fundamental, and is the subject of section 2.2. In subsequent chapters the focus is typically on household income (adjusted for differences in needs) and children are taken to be poor if their incomes fall below a low income threshold. We consider why money-based measures are relevant and whether it is consumption expenditure or income which is the better measure of living standards. Additional issues addressed are the distribution of living standards within families, the choice of the equivalence scale which is used to adjust observed money income (or consumption expenditure) to take account of differences in household size and composition, and of course the level of the poverty line itself. The interval of time over which money-based measures of living standards should be measured is also considered: for example, whether it should be a month or a year.