The Poverty and Social Exclusion Survey of Britain made it possible first time to explore poverty using three different measures applied at the same time on the same sample. The measures were: lacking socially perceived necessities; being subjectively poor and having a relatively low income. These approaches are all commonly used to identify the poor and to measure poverty but rarely if ever in combination. In this article we have found that there is little overlap in the group of people defined as poor by these dimensions. There are reasons for this lack of overlap, connected to the reliability and validity of the different measures. However the people who are defined as living in poverty by different measures of poverty are different. This inevitably means that the policy response to poverty will be different depending on which measure is employed.
We have attempted to analyse overlap in two ways. First, by exploring the dimensions of poverty cumulatively, we have found that, the more dimensions people are poor on, the more they are unlike the non-poor and the poor on only one dimension, in their characteristics and in their social exclusion. Second, by treating particular dimensions as meriting more attention than others, we explored three permutations of this type and concluded that, while each permutation were more unlike the non-poor than those poor on a single dimension, they were not as unlike the non-poor as the cumulatively poor were. These results indicate that accumulation might be a better way of using overlapping measures of poverty than by giving priority to one dimension over another.
The implication of the paper is that it is not safe to rely on one measure of poverty – the results obtained are just not reliable enough. Surveys, such as the Family Resources Survey or the European Community Household Panel, which are used to monitor the prevalence of poverty, need to be adapted to enable results to be triangulated – to incorporate a wider range of poverty measures.