Knowledge that Transforms

Fifty years ago, Harsanyi published the first of his seminal two papers on utilitarianism. His results were derived within the von Neumann Morgenstern expected utility theory. A year later, Savage incorporated subjective probability into expected utility theory in his famous book. In this note we extend Harsanyi’s utilitarianism to Savage’s framework. We show that a Pareto condition implies utilitarian aggregation: both society’s utility function and its probability measure are linear combinations of those of the individuals. This conclusion contrasts the impossibility of reconciling a Pareto condition and linear aggregation of beliefs and tastes, that was noted by several authors. We argue that the indiscriminate Pareto condition considered by these authors is not compelling. Society should not necessarily endorse a unanimous choice when it is based on contradictory beliefs. Restricting the Pareto condition to choices that only involve identical beliefs allows the extension of Harsanyi’s result to Savage’s framework.

We present a North‐South model of international trade in which differentiated products are developed in the North. Sectors are populated by final‐good producers who differ in productivity levels. On the basis of productivity and sectoral characteristics, firms decide whether to integrate into the production of intermediate inputs or outsource them. In either case they have to decide from which country to source the inputs. Final‐good producers and their suppliers must make relationship‐specific investments, both in an integrated firm and in an arm’s‐length relationship. We describe an equilibrium in which firms with different productivity levels choose different ownership structures and supplier locations. We then study the effects of within‐sectoral heterogeneity and variations in industry characteristics on the relative prevalence of these organizational forms.

We investigate whether political jurisdictions form in response to the trade‐off between economies of scale and the costs of a heterogeneous population. We consider heterogeneity in income, race, ethnicity, and religion, and we test the model using American school districts, school attendance areas, municipalities, and special districts. We find strong evidence of a trade‐off between economies of scale and racial heterogeneity; we also find evidence of a trade‐off between economies of scale and income heterogeneity. Conversely, we find little evidence that ethnic or religious heterogeneity shapes jurisdictions. To clarify the direction of causality between heterogeneity and jurisdictions, we exploit shocks to racial heterogeneity generated by the two world wars.

We provide a new and more complete analysis of the origins of the Dust Bowl of the 1930s, one of the most severe environmental crises in North America in the twentieth century. Severe drought and wind erosion hit the Great Plains in 1930 and lasted through 1940. There were similar droughts in the 1950s and 1970s, but no comparable level of wind erosion. We explain why. The prevalence of small farms in the 1930s limited private solutions for controlling the downwind externalities associated with wind erosion. Drifting sand from unprotected fields damaged neighboring farms. Small farmers cultivated more of their land and were less likely to invest in erosion control than larger farmers. Soil conservation districts, established by the government after 1937, helped coordinate erosion control. This “unitized” solution for collective action is similar to that used in other natural resource/environmental settings.

In welfare theory it is standard to pick the consumption stream that maximizes the welfare of the representative agent. We argue against this position, and show that a benevolent social planner will generally place a greater weight on future consumption than does the representative agent. Our analysis has immediate implications for public policy: agents discount the future too much and the government should promote future oriented policies.

In this paper, we exploit new sources of cross-sectional data to estimate a detailed product-level demand system for new passenger vehicles. We use four data sources: on the characteristics of products, on the attributes of the U.S. population of households, on the match between the first and second vehicle choices of the household, and on the match between households attributes and first choice vehicles. We show that these data solve some, but not all, of the traditional problems in estimating differentiated products demand systems and indicate which data sources are important for which problem. The data is rich enough to reveal a rather complex substitution pattern, requiring a quite general modeling framework. Together the data and model make a detailed analysis of industry demand possible. 1 Introduction In Berry, Levinsohn, and Pakes (1995) (BLP) we provide an algorithm for obtaining estimates of demand parameters for a class of differentiated product models. Demand-side models ...

Tax evasion, by its very nature, is difficult to observe. We quantify the effects of tax rates on tax evasion by examining the relationship in China between the tariff schedule and the "evasion gap," which we define as the difference between Hong Kong's reported exports to China at the product level and China's reported imports from Hong Kong. Our results imply that a one-percentage-point increase in the tax rate is associated with a 3 percent increase in evasion. Furthermore, the evasion gap is negatively correlated with tax rates on closely related products, suggesting that evasion takes place partly through misclassification of imports from higher-taxed categories to lower-taxed ones, in addition to underreporting the value of imports.

We develop a theory of internal commitments or “personal rules” based on self‐reputation over one’s willpower, which transforms lapses into precedents that undermine future self‐restraint. The foundation for this mechanism is the imperfect recall of past motives and feelings, leading people to draw inferences from their past actions. The degree of self‐control an individual can achieve is shown to rise with his self‐confidence and decrease with prior external constraints. On the negative side, individuals may adopt excessively rigid rules that result in compulsive behaviors such as miserliness, workaholism, or anorexia. We also study the cognitive basis of self‐regulation, showing how it is constrained by the extent to which self‐monitoring is subject to opportunistic distortions of memory or attribution, and how rules for information processing can themselves be maintained.

The literature offers many explanations for why the IPO market cycles from hot to cold. These include theories in which hot markets represent clusters of IPOs in a new industry, and signaling models that predict that hot markets draw in better quality firms. Others suggest hot market IPOs' stock returns reflect their poor quality. We compare IPOs over cycles during 1975–2000 and find that hot and cold IPO markets do not differ so much in the characteristics of the firms that go public as in the quantity of firms that go public. Both hot and cold IPOs are largely concentrated in the same narrow set of industries and they have few distinctions in profits, age, or growth potential. Our results suggest that hot markets are not driven primarily by changes in adverse selection costs, managerial opportunism, or technological innovations, but more likely reflect greater investor optimism.

In this paper, we analyze the economic value of predicting stock index returns as well as volatility. On the basis of simple linear models, estimated recursively, we produce out-of-sample forecasts for the return on the S&P 500 index and its volatility. Using monthly data, we examine the economic value of a number of alternative trading strategies over the period 1970–2001. It appears easier to forecast returns at times when volatility is high. For a mean-variance investor, this predictability is economically profitable, even if short sales are not allowed and transaction costs are quite large. The economic value of trading strategies that employ market timing in returns and volatility exceeds that of strategies that only employ timing in returns. Most of the profitability of the dynamic strategies, however, is located in the first half of our sample period.