Guglielmo Weber

Is Consumption Growth Consistent with Intertemporal Optimization? Evidence from the Consumer Expenditure Survey

In this paper we show that some of the predictions of models of consumer intertemporal optimization are in line with the patterns of nondurable expenditure observed in U.S. household-level data. We propose a flexible specification of preferences that allows multiple commodities and yields empirically tractable equations. We estimate preference parameters using the only U.S. micro data set with complete consumption information. We show that previous rejections can be explained by the simplifying assumptions made in previous studies. We also show that results obtained using good consumption or aggregate data can be misleading.

Consumption growth, the interest rate and aggregation

In this paper we present empirical evidence on aggregation problems with Euler equations for consumption. Our main results are: estimates of the elasticity of intertemporal substitution for consumption are consistently lower for aggregate data than for average cohort data and the theoretical model is statistically rejected on aggregate data, not rejected on average cohort data. In trying to explain these differences we find that a major role is played by the non-linearity of the estimable equation and by omitted demographic factors (normally unobservable on aggregate data). However, even when these sources of aggregation bias are corrected for, the estimates of the elasticity of intertemporal substitution obtained from aggregate data remain lower than those obtained from average cohort data, and excess sensitivity tests reject the implications of the model. This can be explained as the result of imposing identical coefficients to cohorts who differ in preferences and/or opportunity sets.

Intertemporal substitution, risk aversion and the Euler Equation for consumption

This paper investigates the empirical performance of intertemporal optimization models that relax the restriction imposed by expected utility that risk aversion and intertemporal substitution are negatively related. The authors estimate a system of rates of return and consumption growth equations, and interpret their results in the light of the expected utility, the ordinal certainty equivalence, and the Kreps and Porteus (1978) models. Their results are based on average cohort data for consumption, and thus should not reflect births or deaths. They suggest that non-expected-utility models afford major efficiency gains in the estimation of the elasticity of intertemporal substitution by providing simple cross-equation restrictions. Copyright 1989 by Royal Economic Society.

The UK Consumption Boom of the Late 1980s: Aggregate Implications of Microeconomic Evidence

Two competing explanations of the UK consumer boom in the late 1980s are the financial liberalization-imperfect housing market hypothesis of Muellbauer and Murphy and the hypothesis of King. We use 15 years of Family Expenditure Surveys, and cohort analysis, to investigate to what extent these two hypotheses agree with observed changes in consumption patterns. We find that the housing markets explanation accounts for much of the increase by older cohorts, but cannot be reconciled with the marked rise in expenditure levels of younger households. A simple simulation exercise shows instead that the expectations hypothesis can generate increases of expenditure by young consumers of the magnitude observed in our data. Copyright 1994 by Royal Economic Society.

Changes in Compulsory Schooling, Education and the Distribution of Wages in Europe

Using data from 12 European countries and the variation across countries and over time in the changes of minimum school leaving age, we study the effects of the quantity of education on the distribution of earnings. We find that compulsory school reforms significantly affect educational attainment, especially among individuals belonging to the lowest quantile of the distribution of ability. Contrary to previous findings in the relevant literature, we find that additional education reduces wage inequality below median income and increases it above median income. There is also evidence in our data that education and ability are complements in the production of human capital and earnings. While these results support an elitist education policy – more education to the brightest, they also suggest that investing in the less fortunate but bright could payoff both on efficiency and on equity grounds.

Intertemporal Nonseparability or Borrowing Restrictions? A Disaggregate Analysis Using a U.S. Consumption Panel

We propose a method to test for liquidity constraints which relies on using the within period marginal rate of substitution condition as a benchmark to evaluate the intertemporal Euler equation. If spot markets for nondurable goods exist, but financial markets either do not exist, or are imperfect, we show how the comparison of first order conditions involving the relevant spot and intertemporal prices can be used to detect the imperfection. We apply our methodology to a large sample of U.S. households, drawn from twelve years of the Consumer Expenditure Survey, allowing for a general nonseparable preference structure. Our estimates of first order conditions do not indicate the presence of liquidity constraints, with the possible exception of young households.

Consumer Credit: Evidence from Italian Micro Data

In this paper we analyse unique data on credit applications received by the leading provider of consumer credit in Italy (Findomestic). The data set covers a five-year period (1995-1999) during which the consumer credit market rapidly expanded in Italy and a new law (the usury law) came into force that set a limit on interest rates charged to consumers. We compute behavioural changes by controlling for changes in the observable characteristics of the Findomestic clientele and argue that, under suitable identifying assumptions, these changes can be given a structural interpretation. If the usury shock is assumed to have affected credit supply but not credit demand-that is, if the usury law had a differential impact on the supply of various types of credit but a uniform impact on demand-then we can identify and estimate a demand equation. Our key finding is that demand is interest-rate elastic, particularly in the more affluent North. (JEL: D14, E21, G21) Copyright (c) 2005 by the European Economic Association.

Are Household Portfolios Efficient? An Analysis Conditional on Housing

Standard tests of portfolio efficiency neglect the existence of illiquid wealth. The most important illiquid asset in household portfolios is housing: if housing stock adjustments are infrequent, optimal portfolios in periods of no adjustment are affected by housing price risk through a hedge term and tests for portfolio efficiency of financial assets must be run conditionally upon housing wealth. We use Italian household portfolio data and time series on financial assets and housing stock returns to assess whether actual portfolios are efficient. We find that housing wealth plays a key role in determining whether portfolios chosen by home-owners are efficient.

Income, wealth and financial fragility in Europe

The article examines the distribution of income and wealth among the generation of Europeans aged 65 and over, using data drawn from the first wave of the Survey of Health, Ageing and Retirement in Europe (SHARE). It looks at how cross-country comparisons of income, wealth and debt are affected by differences in purchasing power, household size and taxation, and shows that some seemingly wide international differences appear less so when the proper adjustments are made. The article reveals wide differences in income, wealth and indebtedness of elderly households in Europe, and provides background information on social issues such as the adequacy of savings at retirement, and the financial fragility of the elderly.

Efficient portfolios when housing needs change over the life cycle

We address the issue of the efficiency of household portfolios in the presence of housing risk. We treat housing stock as an asset and rents as a stochastic liability stream: over the life-cycle, households can be short or long in their net housing position. Efficient financial portfolios are the sum of a standard Markowitz portfolio and a housing risk hedge term that multiplies net housing wealth. Our empirical results show that net housing plays a key role in determining which household portfolios are inefficient. The largest proportion of inefficient portfolios obtains among those with positive net housing, who should invest more in stocks.