International Poverty Comparisons on Unit Record Data of Developing and Developed Countries

Cross country poverty comparisons on unit records have, rarely, involved both developing and developed countries. The present study attempts to fill this gap by comparing poverty across fourteen nations with diverse economic and demographic characteristics and at vastly different stages of economic development. The study contains evidence on (a) cross country variation in the equivalence scales estimated in the presence of both household size economies and adult/child relativities, (b) impact of demographic adjustment of the poverty line, that incorporate household size and composition changes, on the poverty rates, and (c) sensitivity of the poverty estimates and their rankings to the ‘equivalence elasticity’. The study finds that country rankings based on per capita GNP bear very little resemblance with that based on the aggregate poverty rates. The latter hide substantial variation in the poverty estimates across different household types.     

A CROSS-COUNTRY STUDY OF EQUIVALENCE SCALES AND EXPENDITURE INEQUALITY ON UNIT RECORD HOUSEHOLD BUDGET DATA

Inequality comparisons require equivalence scales to account for differences in household size and composition. The multiplicity of equivalence scale models makes the sensitivity of the inequality calculations to the scale used a significant policy issue. Such an investigation based on unit records of two adult households from Italy, Australia, South Africa, Thailand, Peru, Philippines, India and Tanzania was our principal motivation. The equivalence scale varies across countries and between different types of children. Inequality rankings of countries, though not the inequality decomposition between households of different composition, are robust to the equivalence scale used.     

EQUIVALENCE SCALE SENSITIVITY OF POVERTY STATISTICS FOR THE MEMBER STATES OF THE EUROPEAN COMMUNITY

Using microdata from Household Budget Surveys of the Member States of the European Community, this paper examines the sensitivity of poverty statistics with respect to the choice of the equivalence scale. The results show that the ranking of the countries with respect to the overall poverty incidence is hardly affected when different equivalence scales are used. However, the composition of the poor population shows considerable changes when e.g. subjective equivalence scales are used instead of the OECD equivalence scale. The poverty incidence among specific household groups, such as single elderly and households with children, is particularly sensitive to the choice of the equivalence scale.     

SEQUENTIAL STOCHASTIC DOMINANCE AND THE ROBUSTNESS OF POVERTY ORDERINGS

When comparing poverty across distributions, an analyst must select a poverty line to identify the poor, an equivalence scale to compare individuals from households of different compositions and sizes, and a poverty index to aggregate individual deprivation into an index of total poverty. A different choice of poverty line, poverty index or equivalence scale can of course reverse an initial poverty ordering. This paper develops easily-checked sequential stochastic dominance conditions that throw light on the robustness of poverty comparisons to these important measurement issues. These general conditions extend well-known results to any order of dominance, to the choice of individual versus family based aggregation, and to the estimation of "critical sets" of measurement assumptions. Our theoretical results are briefly illustrated using data for four countries drawn from the Luxembourg Income Study databases.     

Finding out the Routes to Escape Poverty: The Relevance of Demographic vs. Labor Market Events in Spain

The knowledge of which events are most effective in pushing households out of deprivation should help in designing poverty-alleviating social policy. Using longitudinal data for Spain, we analyze the nature of events pushing poor households out of poverty, adding an interesting decomposition of transitions: the occurrence of an event and the income change implied by it. We find that, similarly to other developed countries, the events that most help Spanish households in leaving poverty are related to changes in labor status of household members. However, non-labor income changes are significantly more important in Spain than elsewhere.     

IS POVERTY INCREASING IN THE DEVELOPING WORLD?

We assess the developing world's progress in reducing poverty during the late 1980s using new data on the distribution of household consumption or income per person for 44 countries. Local currencies are adjusted to purchasing power parity. To assess robustness, restricted dominance tests are applied to the poverty comparisons. An overall decrease in poverty incidence is indicated over a wide range of poverty lines and measures. However the change is small, and numbers of poor increased at roughly the rate of population growth. The experience was diverse across regions and countries; poverty fell in South and East Asia, while it rose in Latin America and Sub-Saharan Africa.     

EQUIVALENCE SCALES, WELL-BEING, INEQUALITY, AND POVERTY: SENSITIVITY ESTIMATES ACROSS TEN COUNTRIES USING THE LUXEMBOURG INCOME STUDY (LIS) DATABASE

The Luxembourg Income Study (LIS) database on which this article is based offers researchers exciting new possibilities for international comparisons based on household income microdata. Among the choices the LIS microdata allows a researcher, e.g. income definition, income accounting unit, etc., is the choice of family equivalence scale, a method for estimating economic well-being by adjusting income for measurable differences in need.
The range of potential equivalence scales that can and are being used in the ten LIS countries and elsewhere to adjust incomes for size and related differences in need span a wide spectrum. The purpose of this paper is to review the available equivalence scales and to test the sensitivity of various income inequality and poverty measures to choice of equivalence scale using the LIS database. The results of our analysis indicate that choice of equivalence scale can sometimes systematically affect absolute and relative levels of poverty; and inequality and therefore rankings of countries (or population subgroups within countries). Because of these sensitivities, one must carefully consider summary statements and policy implications derived from cross-national comparisons of poverty and/or inequality.     

MEASURING POVERTY AND DEPRIVATION IN SOUTH AFRICA

This paper compares a standard expenditure-based poverty measure with a specifically created composite measure of deprivation using household survey data from South Africa. While there is a strong overall correlation between expenditures and levels of deprivation, the correlation is much weaker among the worst-off South Africans. In addition, the two measures differ considerably in the impact of race, headship, location (urban, rural), and household size on expenditure poverty versus deprivation. In general, the deprivation measure finds more Africans, rural dwellers, members of de facto female-headed households, and members of smaller households deprived than expenditure poor. Only the differences in the effect of household size on poverty are sensitive to assumptions about equivalence scales. As a result, the two measures diverge greatly in identifying the poorest and most deprived sections of the population, which may have considerable consequences for targeting.     

RANKING INCOME DISTRIBUTIONS WHEN NEEDS DIFFER

We derive criteria for ranking income distributions where households differ in equity-relevant non-income characteristics ('needs'). using methods which do not require cardinal specifications of equivalence scales. We consider comparisons for situations where the distributions of needs differ (eg. Cross nationally or intertemporally), building on the results of Atkinson and Bourguignon (1987) and Atkinson (1992). The modifications required when the individual rather than the household is the income-receiving unit are also discussed. We illustrate the methods with an analysis of changes in social welfare and poverty in the U.K. between 1981 and 1986.     

WEALTH INEQUALITY AND HOUSEHOLD STRUCTURE: U.S. VS. SPAIN

We study the link between culturally inherited household structure and wealth distribution in international comparisons using household data for the U.S. and Spain (the SCF and the EFF). We estimate counterfactual U.S. distributions relying on the Spanish household structure. Our results show that differences in household structure account for most of the differences in the lower part of the distribution between the two countries, but mask even larger differences in the upper part of the distribution. Imposing the Spanish household structure to the U.S. wealth distribution has little effect on the Gini coefficient and wealth top shares. However, this is the net result of reduced differences at the bottom and increased differences at the top. So there is distinct additional information in considering the whole distribution. Finally, we present results for the within‐group differences between the two countries using quantile regressions and find a reversing pattern by age.     

Reference Income Effects in the Determination of Equivalence Scales Using Income Satisfaction Data

We estimate household equivalence scales, i.e. the needs of additional adults and children relative to a single adult, using income satisfaction data from the German Socio‐Economic Panel. We extend previous studies applying this approach by taking reference income into account. This allows separating needs‐based from reference effects in the determination of income satisfaction. We show that this adjustment helps to overcome a bias causing an overestimation of adults’ and an underestimation of children’s needs‐based equivalence weights. Our results indicate that controlling for income comparisons substantially increases children’s equivalence weight relative to that of adults.     

How to Compare Apples And Oranges: Poverty Measurement Based on Different Definitions of Consumption

Poverty rates calculated on the basis of household consumption expenditures are routinely compared across countries and time. The surveys which underlie these comparisons typically differ in the types of food and non-food expenditures included, often in ways which are easily overlooked by analysts. With several examples we demonstrate that these commonly occurring variations in expenditure definitions can give rise to marked differences in poverty rates where there are no real differences in well-being. We show that one approach to calculating poverty lines, used with the headcount measure of poverty, can allow comparisons based on data with different definitions of consumption. In addition to allowing comparative poverty analysis using existing survey data, the results suggest that poverty monitoring could be done effectively at lower cost by alternating detailed expenditure surveys with far more abbreviated surveys.     

THE SENSITIVITY OF INTERNATIONAL POVERTY COMPARISONS

Using data from the Luxembourg Income Study, I study the sensitivity of cross-national income poverty comparisons to the method in which poverty is measured. Absolute poverty comparisons that keep the purchasing power at the poverty line constant across countries lead to conclusions that differ from relative poverty comparisons in which the real value of the poverty line varies with average income. The absolute poverty ranking of countries also varies as the real value of the poverty line is lowered. Cross-national differences in household characteristics are largely irrelevant in explaining poverty differences.     

IS THERE BIAS IN COMPUTING HOUSEHOLD EQUIVALENCE SCALES?

Household equivalence scales are often used to help perform welfare comparisons across households with different demographic composition. Abstracting from the problems of value judgments and ethical standards, the use of equivalence scales to perform welfare comparisons still faces several measurement problems, namely the identification problem and the endogeneity problem. This paper introduces and estimates an unconditional demand system that simultaneously addresses these two problems. By explicitly considering the demand for leisure, and the fact the household can choose some of its demographic characteristics, we deal with the endogeneity problem and obtain consistent estimates. We identify unconditional equivalence scales by estimating the demand for endogenous demographic variables along with the demand for leisure and consumer goods. More general equivalence scales allowing for better comparability are estimated and used for welfare comparisons.     

“When Life Gives You Lemons”: Using Cross-Sectional Surveys to Identify Chronic Poverty in the Absence of Panel Data

At the core of poverty eradication is the need to eliminate that poverty that is persistent over time (chronic poverty). Unfortunately, traditional approaches to identifying chronic poverty require longitudinal data that is rarely available. In its absence, this paper proposes an alternative approach that only requires 1 year of cross-sectional data on monetary and non-monetary poverty. It puts forth two conjectures and contends that the combined profile of a household as both income poor and multidimensionally poor can be used as a proxy of that household being chronically income poor. To explore the viability of this approach, we use a probit model and longitudinal data for three Latin American countries to estimate households’ probabilities of remaining in income poverty based on their past income and multidimensional poverty statuses. We find empirical support for the approach that is significant, consistent across countries, and robust to various controls and periods of analysis.     

MEASURING POVERTY USING BOTH INCOME AND WEALTH: A CROSS‐COUNTRY COMPARISON BETWEEN THE U.S. AND SPAIN

We study the correspondence between a household's income and its vulnerability to income shocks in two developed countries: the U.S. and Spain. Vulnerability is measured by the availability of wealth to smooth consumption in a multidimensional approach to poverty, which allows us to identify three groups of households: the twice‐poor group, which includes income‐poor households who lack an adequate stock of wealth; the group of protected‐poor households, which are all those income‐poor families with a buffer stock of wealth they can rely on; and the vulnerable‐non‐poor group, including households above the income‐poverty line that do not hold any stock of wealth. Interestingly, the risk of belonging to these groups changes over the life‐cycle in both countries while the size of the groups differs significantly between Spain and the U.S., although this result is quite sensitive to whether the housing wealth component is included in the wealth measure or not.     

DIFFERENCES IN NEEDS AND ASSESSMENT OF INCOME DISTRIBUTIONS*

The literatures on the assessment of income distributions and on differences in needs are not well integrated. The theoretical literature providing results about evaluations and comparisons of income distributions does not, in the main, consider the implications of non-income differences between income-receiving units, while the equivalence scale literature providing results about the relationship between living standards, incomes and household composition does not consider distributional implications. The aim of this survey is to go some way towards integrating these separate literatures; to consider how to evaluate and compare income distributions while at the same time taking explicit account of differences in household composition.     

WEALTH HOLDINGS AND POVERTY STATUS IN THE U.S.

Families below the poverty line are better off in terms of wealth than income. In 1962, the ratio of mean income between families below and above the poverty line is 0.19 and the ratio of mean wealth is 0.29. The corresponding ratios for 1983 are 0.16 and 0.19. On average, the elderly poor are better off in terms of wealth than the younger poor, particularly relative to their own income. However, the poor have become worse off in terms of wealth between 1962 and 1983, when their real income grew by 6 percent and their real wealth declined by 11 percent. The inclusion of pension and social security wealth in the household portfolio narrows the wealth gap between the poor and non-poor, particularly for families under 65 years of age. Alternative poverty rates are also calculated based on the inclusion of annuity flows from wealth in household income. The reduction in the poverty rate between 1962 and 1983, from 21 to 15 percent on the basis of the official rate, is considerably lower with these alternative definitions.     

FOOD NEEDS AND ABSOLUTE POVERTY IN URBAN SOUTH AMERICA

The minimum cost of an adequate diet, following food preferences, is estimated for families in ten South American cities in five countries, allowing for household composition by age and sex. The ratio of actual expenditure on food and beverages to this normative expenditure is then used to rank families in six classes, of which the bottom two correspond to absolute poverty, or to actual expenditure less than the estimated minimum. Three questions can then be explored: which families appear to be poor, on this measure? how do such families allocate their spending toward other items such as housing? and, does this indicator of poverty classify families in much the same way as other proposed measures? The results suggest some under-reporting of food spending in the poorest class, but otherwise the ratio of reported to normative spending gives good results, free from the errors in other parts of the budget and the arbitrariness of indicators which depend on socially-defined rather than physiological “needs.” Poor families tend to be large, with many children; to have many dependents per income recipient; to have male working members other than the head; to suffer unemployment of members other than the head; to have relatively low levels of schooling; and to show high density in housing. Even quite poor households spend appreciable amounts on housing and on education, while not satisfying all food needs; both kinds of spending increase rapidly as food requirements are met. There are no consistent relations between poverty and type of employment or the share of income attributed to the head. The data refer to 1966–69 and are highly comparable; all monetary estimates are in dollars of equal purchasing power.     

A SIMPLIFIED MODEL FOR SOCIAL WELFARE ANALYSIS: AN APPLICATION TO SPAIN, 1973–74 TO 1980–81

Most of the literature on income distribution has concentrated on inequality. In this paper we introduce a concern for efficiency in a social welfare model. We propose a simple but useful specification which combines three features: (i) the selection of measurement instruments in the relative and the absolute case on the grounds of their properties for applied work; (ii) a procedure to make welfare comparisons across households with different needs, in a model in which equivalence scales depend only on house-hold size; and (iii) the use of household specific statistical price indices to make intertemporal comparisons in real terms. The methodology is applied to the study of the role of prices and demographic effects in the evolution of the standard of living in Spain from 1973–74 to 1980–81.