DO HMOS ENCOURAGE PREVENTION? AN ANALYSIS OF ALTERNATIVE HEALTH CARE PLANS

We examine consumers' choice of preventive care and providers' choice of capacity (which affects the transaction costs of consuming health care) under alternative health care financing plans. We show that consumers choose Pareto-optimal prevention and providers choose optimal capacity under a pure feE-for-service (FFS) plan and under a mixed plan that includes an up-front fee and a fee for service. Under a pure prepaid plan, however, consumers may over- or underconsume prevention. In the former case, capacity restrictions under such a plan (e.g., long office waits, limited options) may be interpreted as a second-best response to overconsumption. We also find that the dollar costs of health care are higher under the prepaid plan. These conclusions cast doubt on some of the presumed advantages of HMOs.     

The Effect Of Stock Splits On Liquidity And Excess Returns: Evidence From Shareholder Ownership Composition

We examine the influence of firm ownership composition on both the abnormal returns at the announcement of a stock split and liquidity changes following a stock split. We find three results. First, the largest post‐split increase in institutional ownership occurs for firms that had low institutional ownership before the split. Second, changes in liquidity are negatively related to the level of institutional ownership before the split. Last, the abnormal return following a split is negatively related to the level of institutional ownership before the split. These findings are important as they shed new light on the source of stock split announcement returns.     

The stylized facts about the behavior of manufacturers' inventories and backorders over the business cycle: 1959–1980

Recent theoretical work has highlighted the role of inventories in propagating business cycles. This paper attempts to provide an empirical foundation for current and future research on the role inventories play in business cycles. The evidence presented here indicates that inventories and backorders are major variables in predicting output fluctuations. Further, the evidence is that disaggregating inventories by stage-of-fabrication is important in predicting output. In concert with previous findings, our results suggest that disaggregated inventories ought to be a component of models of the business cycle.     

Terms of trade risk with partial labor mobility

We examine the welfare consequences of terms-of-trade risk in a small open economy in which it is costly for workers to move between sectors. Relocation costs lead to partial labor mobility, sectoral wage gaps and income risk exceeding that of an economy in which relocation is costless. Using observed wage differentials and standard values for volatility and preferences, we find that the welfare cost of partial labor mobility alone is unlikely to be very large, even in the absence of self-insurance arrangements. In addition, modest consumption substitution elasticities significantly reduce these welfare costs.     

Marginal q,Tobin's q,Cash Flow,and Investment

Many studies of the determinants of investment use Tobin's q to control for the investment opportunities of a firm. Tobin's q roughly measures the average return on a firm's capital anticipated by the market. More relevant for investment decisions, however, is the marginal return on capital. In this paper we estimate investment and research and development (R&D) equations using a measure of marginal q. We use marginal q to identify the existence of cash constraints and managerial discretion and as a separate explanatory variable. For a sample of 560 U.S. firms observed over the 1977-1996 period we present evidence confirming the existence of both cash constraints in some companies and managerial discretion in others.     

Measuring and Assessing Vertical Ties in the Agro-food System

This paper examines the extent to which the concept of vertical coordination in the agro-food sector lends itself to specification or measurement in a manner that is analytically useful. Based on a combination of theory and empirical evidence, it is suggested that vertical organization can be specified as a parameter, variable in degree of control by principal over agent. Such a specification has potential application in analytical models concerned with what gives rise to vertical ties and/or their economic consequences. Drawing principally on the concepts of transactions costs, factor price distortion, and vertical restraint, analytical attention is directed to the economic incentives for, and performance implications of the use of linkages other than spot market transactions for coordinating vertically interdependent stages in the food chain. Research challenges are identified.     

Adding and subtracting Black-Scholes: A new approach to approximating derivative prices in continuous-time models

We develop a new approach to approximating asset prices in the context of continuous-time models. For any pricing model that lacks a closed-form solution, we provide a closed-form approximate solution, which relies on the expansion of the intractable model around an “auxiliary” one. We derive an expression for the difference between the true (but unknown) price and the auxiliary one, which we approximate in closed-form, and use to create increasingly improved refinements to the initial mispricing induced by the auxiliary model. The approach is intuitive, simple to implement, and leads to fast and extremely accurate approximations. We illustrate this method in a variety of contexts including option pricing with stochastic volatility, computation of Greeks, and the term structure of interest rates.     

The fundamentals of land prices and urban growth

In a very simple model in which capital is durable and landowners have perfect foresight, the price of urban land has four additive components: the value of agricultural land rent, the cost of conversion, the value of accessibility, and the value of expected future rent increases, a growth premium. In rapidly growing cities, the growth premium may easily account for half of the average price of land and may create a large gap between the price of land at the boundary (minus conversion cost) and the value of agricultural land rent.