This paper examines firms' problem of how to motivate risk-averse workers not to shirk when workers' utility functions are unknown. The problem is studied in a 2-period setting in which a worker's actions today can influence not only his compensation today but the firms' beliefs about his preferences. Firms cannot credibly commit to ignore the revealed information, so workers' actions today affect their future compensation contracts. It is shown that, in the Wilson/Miyazaki equilibrium, firms may pool workers and learn about their types gradually over time rather than inducing them to separate and reveal their types immediately.

"This paper designs a multiarmed bandit (MAB) sequential model for the analysis of the migration-job search process. The implications either are compatible with well-known migration behavior or, when novel, are also plausible. For example, regions with large wage variability attract migrants, and regions with large nonpecuniary returns increase both in migration and out migration. A major advantage of this approach is the relative ease with which martingale estimators can be derived from the martingale structure of the model. These martingale methods are exemplified for the return migration phenomenon."

JN THE LAST DECADE, the levels of unemployment in industrialized countries have risen dramatically. Rates now are typically two, and in some cases, three and four times those prevailing in the 1950s and 1960s. The fact that these new higher levels are widely tolerated suggests that our thinking about the meaning and significance of unemployment has changed enormously over the period. Such a change is certainly present in the thinking among professional economists. In the 1960s the standard view was that the unemployed represented unutilized resources; their existence in an economy where the vast majority of people had unsatisifed wants was seen as a major social paradox and the most important unsolved intellectual puzzle of the capitalist economic system. This fed the rationale for Keynesian countercyclical fiscal policy and government deficit spending: The government could reasonably print money in order to hire the unemployed because the resources absorbed in the process were essentially free Today, a good number of professional economists, certainly in the United States but to a lesser extent throughout the world, have come to view measured unemployment in industrial economies as an artifact in at least three senses. It is a statistical artifact of a measurement process that classifies as unemployed people who are not really available for work. It is an institutional artifact of a system of social insurance and public welfare that encourages an extension of the process of job search. And it is an artifact of the language that uses a term which in everyday parlance means forced idleness for activities that have important productive functions akin to the functions of inventories, information processing, and investment associated with the utilization of capital goods. These interpretations to be sure hardly constitute a consensus about the meaning of unemployment. But they are no more diverse than the range of views that underlay the older orthodoxy. And for policy makers and economic researchers, they carry a single message: There are many more serious problems toward which to direct attention. These new views about unemployment were developed out of a set of ideas originally associated with the Chicago School of economics, where the emphasis-at once positive and normative-was placed on the competitive market as the gover* A Review of Alexander Keyssar, Out of Work: The First Century of Unemployment in Massachusetts. Cambridge: Cambridge University Press, 1986 and Robert Salais, Nicolas Baverez, and B6nedicte Reynaud, L'invention du chomage: Histoire et transformations d'une categorie en France des annees 1890 aux annees 1980. Paris: Presses Universitaires de France, 1986.

In the market for lawyers, observable data on promotion and turnover can be explained by reference to the idea that there is positive assortative mating of lawyers and legal claims. There is a scale-of-resources effect, under which it is optimal to assign larger claims to lawyers of higher quality. In a law firm the institution of "tenure" performs a sorting function. Lawyers found to be of high quality are given tenured positions, and the rest leave. The value of legal claims handled by a firm determines its sorting problem, which in turn determines its promotion ladder and turnover.

This study examines the ex-dividend day behavior of common stock prices before the enactment of the federal income tax. On ex-dividend days during the pre-tax period, stock prices fell, on average, by the full amount of the dividend. The data are consistent with the hypothesis that (i) investors in the pre-tax period value dividends and capital gains as perfect substitutes and (ii) the differential taxation of dividends and capital gains has since caused investors to discount the value of taxable cash dividends in relation to capital gains.

Fama's evidence that the term premium on Treasury securities is not monotonically increasing is found to depend entirely on the behavior of bid-asked mean returns on 9- and 10-month bills, and only during the subperiod 8/64–12/72. When transactions costs, as reflected in the bid-asked spread, are taken into account, there is found to be no way to exploit this non-monotonicity. The anomalous behavior of the quotations is attributed to the Treasury's auctions of 9-month bills during the period 9/66–10/72. The hypothesis that the term premium is a monotonically increasing function of maturity remains unrefuted.