Money and Economic Activity, Inventories, and Business Cycles

摘要

Incomplete information is a necessary condition for any real effects produced by monetary impulses. An alternative to the local-global inference problem is explored in this paper. Agents are confronted with permanent and transitory shocks. Even with full knowledge about the stochastic structure their best perception at any particular time will usually be erroneous Prices for each period are set at the beginning of the period on the basis of market conditions The realization of the shock process thus creates a short-run u27disequilibriumu27 absorbed by inventory adjustments. This adjustment translates perceived transitory monetary shocks into serially correlated output movements. The analysis proceeds within the context of rational expectations it offers a generalization of equilibrium analysis in two respects. Prices are always in equilibrium relative to perceived conditions, but they do not reflect all ongoing shocks. Quantity adjustments reflect the perceived transitory shocks. The framework used involves moreover a stock-flow interaction operated by inventory adjustments. The stock-flow interaction imposes at any time a future expected adjustment path (for price-level and quantities) to the systemu27s unique stock equilibrium. A major implication of the analysis resolves a puzzle experienced in a recent paper by Robert Hall. It reconciles intertemporal substitution with lagged effects of monetary impulses. It also reconciles small and inconclusive cyclic movements in real wages with the occurrence of production function and large variations in unemployment. Lastly the nature of the inference problem determined by the pattern of incomplete information produces serially correlated movements conditioned on large permanent shocks.