The Joint identification of utility and discount functions from stated choice data: An application to durable goods adoption

We present a survey design that generalizes static conjoint experiments to elicit inter-temporal adoption decisions for durable goods. We show that consumers’ utility and discount functions in a dynamic discrete choice model are jointly identified using data generated by this specific design. In contrast, based on revealed preference data, the utility and discount functions are generally not jointly identified even if consumers’ expectations are known. The separation of current-period preferences from discounting is necessary to forecast the diffusion of a durable good under alternative marketing strategies. We illustrate the approach using two surveys eliciting Blu-ray player adoption decisions. Both model-free evidence and the estimates based on a dynamic discrete choice model indicate that consumers make forward-looking adoption decisions. In both surveys the average discount rate is 43 percent, corresponding to a substantially higher degree of impatience than the rate implied by aggregate asset returns. The estimates also reveal a large degree of heterogeneity in the discount rates across consumers, but only little evidence for hyperbolic discounting.     

On the consequences of state dependent preferences for the pricing of financial assets

This paper introduces state dependent utility into the standard Mehra and Prescott [J. Monet. Econ. 15 (1985) 145] economy by allowing the representative agent's coefficient of relative risk aversion to vary with the underlying economy's growth rate. Existence of equilibrium is proved and its asymptotic properties analyzed. This generalization leads to level dependent marginal rates of substitution, a property that sharply distinguishes this model from the standard construct. For very low coefficients of relative risk aversion, the equilibrium risk free and risky security returns are demonstrated to have volatilities and an associated equity premium that substantially exceed what is found in the data. This provides a contrasting perspective on the classic “equity premium puzzle.”     

Financial Modeling in a Fast Mean-Reverting Stochastic Volatility Environment

We present a derivative pricing and estimation methodology for a class of stochastic volatility models that exploits the observed 'bursty' or persistent nature of stock price volatility. Empirical analysis of high-frequency S&P 500 index data confirms that volatility reverts slowly to its mean in comparison to the tick-by- tick fluctuations of the index value, but it is fast mean- reverting when looked at over the time scale of a derivative contract (many months). This motivates an asymptotic analysis of the partial differential equation satisfied by derivative prices, utilizing the distinction between these time scales. The analysis yields pricing and implied volatility formulas, and the latter provides a simple procedure to 'fit the skew' from European index option prices. The theory identifies the important group parameters that are needed for the derivative pricing and hedging problem for European-style securities, namely the average volatility and the slope and intercept of the implied volatility line, plotted as a function of the log- moneyness-to-maturity-ratio. The results considerably simplify the estimation procedure. The remaining parameters, including the growth rate of the underlying, the correlation between asset price and volatility shocks, the rate of mean-reversion of the volatility and the market price of volatility risk are not needed for the asymptotic pricing formulas for European derivatives, and we derive the formula for a knock-out barrier option as an example. The extension to American and path-dependent contingent claims is the subject of future work. This revised version was published online in August 2006 with corrections to the Cover Date.     

Labour Relations and Asset Returns

This paper proposes a dynamic GE model with standard business cycle properties that also achieves a satisfactory replication of the major financial stylized facts. We ride on two major ideas. First, we show that operating leverage, originating in the priority status of wage claims given the observed business cycle characteristics of the latter, magnifies the risk properties of the residual payments to firm owners and justifies a substantial risk premium. Further we build on the observation that the low frequency variations in income shares constitute a significant source of risk, one that is unlikely to be insurable. When we price this risk in an incomplete market framework, we obtain a GE model with return volatilities close to observations and a sizable equity premium. This is accomplished in a world of low risk aversion and standard utility function but with agent heterogeneity. Workers with restricted access to financial markets are insured by firms and the consumption and preferences of firm owners solely determine the pricing kernel.     

Public pensions and growth

This paper investigates the relationship between the size of an unfunded public pension system and economic growth in an overlapping generation economy, in which altruistic parents finance the education of their children and leave bequests. Unlike the existing literature, we model intergenerational altruism by assuming that children's income during adulthood is an argument of parental utility. Unfunded public pensions can promote growth when families face liquidity constraints preventing them from investing optimally in the education of their children. We consider two alternative ways of financing a public pension system, either by levying social contributions in a lump-sum manner or in proportion to labour income. We find that there is no case for unfunded public pensions in economies where bequests are operative. By contrast, there exists a growth-maximising size of the public pension system in economies where bequests are not operative and individuals are sufficiently patient.     

Recycling under a material balance constraint

In this paper we analyze the dynamic implications of recycling for resource use, the level of economic activity and the long-run development of the economy. In contrast to former approaches, we take explicit account of the circulation of matter in the economy. We consider virgin resources and recycled wastes as essential inputs to production. These material inputs either end up as waste after consumption or are bound in the capital stock—depending on the utilization of the produced output. As accumulating wastes can be recycled and again be employed in production, the waste stock serves as a source of valuable inputs in our model. We focus on the implications of recycling-related market failures and the integration of material balances on the dynamics of the economy. It is shown that a market for waste and subsidies to resource extractors and recycling firms can restore optimality in the decentralized economy.     

Equilibrium asset pricing with systemic risk

We provide an equilibrium multi-asset pricing model with micro- founded systemic risk and heterogeneous investors. Systemic risk arises due to excessive leverage and risk taking induced by free-riding externalities. Global risk-sensitive financial regulations are introduced with a view of tackling systemic risk, with Value-at-Risk a key component. The model suggests that risk-sensitive regulation can lower systemic risk in equilibrium, at the expense of poor risk-sharing, an increase in risk premia, higher and asymmetric asset volatility, lower liquidity, more comovement in prices, and the chance that markets may not clear. We thank Michel Habib, José Scheinkman, Hyun Shin and two anonymous referees for their helpful comments. Jean-Pierre Zigrand is a lecturer in Finance at the LSE, and is the corresponding author. The authors would like to acknowledge financial support under the EPSRC Grant GR/S83975/01 at the Financial Markets Group, London School of Economics.