Research Database

Theory typically does not give us reason to believe that economic models ought to be formulated at the same level of time aggregation at which data happen to be available. Nevertheless, this is frequently done when formulating econometric models, with potentially important specification-error implications. This suggests examining the alternatives, one of which is to model in continuous time. The primary difficulty in inferring the parameters of a continuous time model given sampled observations is the “aliasing identification problem.” This paper shows how the restrictions implied by rational expectations sometimes do, and sometimes do not, resolve the problem. This is accomplished very simply in the context of a hypothesis about the term structure of interest rates. The paper confirms and extends results obtained for another example by Hansen and Sargent.

A new approach to market behavior is suggested. This approach has a coherent game theoretic foundaton, addresses such anomalous economic behaviors as strikes, rigid wages and unemployment, regulation of financial markets, depresssion, and nonmarket allocation, and, more generally, provides insights for Finance, Oligopoly Theory, Industrial Organization, and Macroeconomics. The central theme of the approach is that exchange technologies are a basic building block in a model, as are tastes, endowments, and production technologies. Moreover, the key feature of an institution of exchange is that it allows the making of a binding final offer.

A model is presented in which demand deposits backed by fractional currency reserves and public insurance can be beneficial. The model uses Samuelson's pure consumption-loans model. The case for demand deposits, reserves, and deposit insurance rests on costs of illiquidity and incomplete information. The effect of deposit insurance depends upon how, and at what cost, the government meets its insurer's obligation--something which is not specified in practice. It remains possible that demand deposits and deposit insurance are a distortion, and reserve requirements serve only to limit the size of this distortion.

In this paper we consider a particular international economic policy regime: the laissez-faire regime, the distinguishing features of which are unrestricted portfolio choice and floating exchange rates. And as we show, that regime, although favored by many economists, is not economically feasible. It does not have a determinate equilibrium. That is an implication of an over-lapping-generations model. But as we argue in the paper, that is no reason for doubting the indeterminacy of the laissez-faire regime equilibrium.

A critical roadblock to modelling inventories of finished goods has been the claim that production and inventory decisions of a perfectly competitive firm are determined independently of each other. A basic goal of this study is to specify fundamental preferences of economic agents, technologies, constraints and market structures that are, in a rough way, capable of generating patterns of serial correlation and cross correlation between inventories and employment of factors of production that are consistent with those observed in the data. The claim is made that the time series for inventories, output and employment can be interpreted as emerging from a well specified dynamic, stochastic competitive equilibrium in which economic agents are assumed to form rational expectations about variables not included in their information sets. Inventories and employment will not be related in a direct way if and only if the price elasticity of demand for output is equal to infinity.