Knowledge that Transforms

Recent work by David Lilien has argued that the positive correlation between the dispersion of employment growth rates across sectors (σ) and the unemployment rate implies that sectoral shifts in labor demand are responsible for a substantial fraction of cyclical variation in unemployment. This paper demonstrates that, under empirically satisfied conditions, traditional single-factor business-cycle models will produce a positive correlation between σ and the unemployment rate. Information on the job vacancy rate permits one to distinguish between a pure sectoral shift and a pure aggregate demand interpretation of this positive correlation. The finding that σ and the volume of help wanted advertising (a job vacancy proxy) are negatively related supports an aggregate demand interpretation.

This paper develops and applies a novel test of the Holt et al. linear quadratic inventory model. It is shown that a central property of the model is that a certain weighted sum of variances and covariances of production, sales, and inventories must be nonnegative. The weights are the basic structural parametersof the model. The model may be tested by seeing whether this sum is in fact nonnegative. When the test is applied to some nondurables data aggregated to the two-digit SIC code level, it almost always rejects the model, even though the model does well by traditional criteria.

This paper presents a discrete-time version of Jovanovic's model of worker-firm matching. Descriptive evidence is presented that supports the notion that unobserved worker-firm heterogeneity is an important component in the intertemporal structure of wages for young workers. A structural econometric model of wage dynamics under worker-firm sorting is developed and estimated. Finally, a formal test of the matching model is carried out, and the matching structure on intertemporal covariances of wages is not rejected. My results indicate the necessity of jointly considering processes of turnover and wage growth when analyzing the labor market experiences of young workers.

The recent literature on employment contracts emphasizes that it is in the interests of the parties to produce institutional arrangements that lead to employment contracts that we have termed "strongly efficient." Strong efficiencyimplies that employment is set so as to equate the marginal revenue product of workers to their alternative wage. It follows that employment in such contracts fluctuates with the determinants of a worker's marginal revenue product and with the worker's alternative wage, but not with the observed contract wage. We have examined two kinds of evidence to test the strong efficiency hypothesis. Laboratory experiments by Siegel et al. indicate that this hypothesis is strongly confirmed when the bargaining parties are required to agree on price and quantity simultaneously and is strongly rejected when the parties are required to bargain by a system of price leadership. In our field data on the printing trades, we find no convincing evidence of strong efficiency. We have also examined the evidence in support of what we have called the "weak efficiency hypothesis." According to this hypothesis, both the contract wage and the alternative wage determine employment. We have found only mixed support for this hypothesis because our measures of the alternative wage available to workers are frequently positively related to employment, precisely the contrary to the hypothesized direction of this effect in a weakly efficient contract.

This paper uses a two-country general equilibrium model of the world economy in order to analyze the effects of budget deficits and government spending on world rates of interest, consumption, and international indebtedness. It demonstrates the difference between the effects of fiscal expenditures and tax cuts as well as between the effects of current policies and expected future policies. It is shown that the qualitative effects of fiscal policies depend on whether the country introducing the policies runs a surplus or a deficit in its current account. Following the positive analysis of the short-run and the steady-state effects, the paper concludes with a normative analysis of the welfare implications of budget deficits.

In the most frequently used microdata sets, over a quarter of all respondents now refuse to answer some questions about their incomes. The Census Bureau has dealt with this problem, which has been increasing in severity over time, by imputing incomes of non-respondents. Their imputation procedure, called the "hot deck," essentially matches nonrespondents with demographically similar donors. In this paper we evaluate the census imputation methodology and raise some questions. First, the census procedure is tied to commonality of events in the population rather than the more appropriate informational content of regressors. Clearly, the census procedure severely understates income in certain occupations. Because it is based on the apparently invalid assumption that income does not affect reporting propensities, it most likely understates average incomes as well.

Evidence has recently been presented by Salih Neftçi to support the hypothesis that recessions in economic activity tend to be steeper and more short-lived than recoveries in economic activity. That evidence, however, was confined to the behavior of the unemployment rate in the United States. In this paper it is shown that when Neftçi's methods are applied to analyze the behavior of real gross national product, investment, and productivity in the United States or when they are used to analyze industrial production abroad, the asymmetry hypothesis seems to be less compelling.

This paper investigates the possibility that the observed deviations of major bilateral exchange rates from values implied by market fundamentals are a consequence of rational asset market bubbles. When a new econometric methodology for detecting asset market bubbles is used, the joint hypothesis of no bubbles and stable autoregressive processes for relative money supplies and real incomes is rejected for the dollar/deutsche mark and dollar/pound ratesusing monthly data over the period 1973-82. Additional tests for coefficient stability and for lack of cointegration between exchange rates and market fundamentals suggest that the bubble findings must be interpreted with care.

We generate an empirical method aimed at predicting the timing and magnitude of devaluations forced by speculative attacks on fixed exchange rate systems. Using the Mexican experience as an example, we produce time-series estimates of the one-period-ahead probability of devaluation, the expected value of the new fixed exchange rate, and the confidence interval of the forecasted exchange rate. The results of the empirical exercise are encouraging. Devaluations, both in and out of sample, did occur when "predicted" by the model. Furthermore, the probabilities of devaluation reached relatively high values prior to actual devaluations.

The paper describes an artificial economy in which firms in different sectors make inventions at different times but innovate simultaneously to take advantage of high aggregate demand. In turn, high demand results from simultaneous innovation in many sectors. The economy exhibits multiple cyclical equilibria, with entrepreneurs' expectations determining which equilibrium obtains. These equilibria are Pareto ranked, and the most profitable equilibrium need not be the most efficient. While an informed stabilization policy can sometimes raise welfare, if large booms are necessary to cover fixed costs of innovation, stabilization policy can stop all technological progress.