This paper sets out necessary and sufficient empirical conditions for rational intrinsic habits models in the revealed preference tradition of <cross-ref type="bib" refid="R41">Samuelson (1948)</cross-ref>, <cross-ref type="bib" refid="R29">Houthakker (1950)</cross-ref>, <cross-ref type="bib" refid="R3">Afriat (1967)</cross-ref>, and <cross-ref type="bib" refid="R11">Browning (1989)</cross-ref>. The conditions in the paper are shown to be computationally straightforward and to yield set identification for certain features of the model. The ideas outlined are applied to a microeconomic panel dataset. The addition of habit formation to the discounted utility model is shown to improve the rationalizability of the microdata considerably. Even if habit formation is rejected, it is shown that modest and plausible allowance for heterogeneity in prices and interest rates is sufficient to bring consumption behaviour into line with the theory.

This paper uses revealed preference inequalities to provide the tightest possible (best) nonparametric bounds on predicted consumer responses to price changes using consumer-level data over a finite set of relative price changes. These responses are allowed to vary nonparametrically across the income distribution. This is achieved by combining the theory of revealed preference with the semiparametric estimation of consumer expansion paths (Engel curves). We label these expansion path based bounds on demand responses as E-bounds. Deviations from revealed preference restrictions are measured by preference perturbations which are shown to usefully characterize taste change and to provide a stochastic environment within which violations of revealed preference inequalities can be assessed.

A well-known problem with revealed preference methods is that when data are found to satisfy their restrictions it is hard to know whether this should be viewed as a triumph for economic theory, or a warning that these conditions are so undemanding that almost anything goes. This paper allows researchers to make this distinction. Our approach uses an axiomatic characterization of a measure of predictive success due to Selten (1991). We illustrate the idea using a panel dataset. The results show that this approach can lead us to radically reassess our view of the empirical performance of economic theory. JEL: D11, D12

This article provides a revealed preference characterisation of quasi-hyperbolic discounting which is designed to be applied to readily available expenditure surveys. We describe necessary and sufficient conditions for the leading forms of the model and also study the consequences of the restrictions on preferences popularly used in empirical lifecycle consumption models. Using data from a household consumption panel dataset, we explore the prevalence of time-inconsistent behaviour. The quasi-hyperbolic model provides a significantly more successful account of behaviour than the alternatives considered. We estimate the joint distribution of time preferences and the distribution of discount functions at various time horizons.

Characteristics models have been found to be useful in many areas of economics. However, their empirical implementation tends to rely heavily on functional form assumptions. In this paper we develop a revealed preference approach to characteristics models. We derive the necessary and sufficient empirical conditions under which data on the market behaviour of heterogeneous, price-taking consumers are non-parametrically consistent with the consumer characteristics model. Where these conditions hold, we show how information may be recovered on individual consumers' marginal valuations of product attributes. In some cases, marginal valuations are point identified, and in other cases, we can only recover bounds. Where the conditions fail, we highlight the role which the introduction of unobserved product attributes can play in rationalizing the data. We implement these ideas using consumer panel data on the Danish milk market.

Changes in product characteristics on the extensive margin (the addition of new features and the removal of old ones) are an important and hitherto neglected dimension of quality change. Standard techniques for adjusting price indices for new goods cannot handle such changes satisfactorily, and this leads to an economically and statistically significant bias in the measurement of prices and real output. We combine insights from the theories of exact index numbers and demand for characteristics to develop a new method for incorporating changes on the extensive characteristic margin. Applied to U.K. data on new car sales, our method leads to revisions in estimated inflation rates for this commodity group that are both plausible and quantitatively important.

Testing for a Reference Consumer in International Comparisons of Living Standards by Ian Crawford and J. Peter Neary. Published in volume 98, issue 4, pages 1731-32 of American Economic Review, September 2008

This paper applies revealed preference theory to the nonparametric statistical analysis of consumer demand. Knowledge of expansion paths is shown to improve the power of nonparametric tests of revealed preference. The tightest bounds on indifference surfaces and welfare measures are derived using an algorithm for which revealed preference conditions are shown to guarantee convergence. Nonparametric Engel curves are used to estimate expansion paths and provide a stochastic structure within which to examine the consistency of household level data and revealed preference theory. An application is made to a long time series of repeated cross-sections from the Family Expenditure Survey for Britain. The consistency of these data with revealed preference theory is examined. For periods of consistency with revealed preference, tight bounds are placed on true cost of living indices.