Excess Entry in the Absence of Scale Economies

It is well-known that with free entry, more firms than is socially optimal typically enter provided there are economies of scale. This paper investigates the possibility of excess entry in the absence of scale economies We thank Simon Anderson, Tom Holmes, the late Arijit Mukherji, and Xavier Vives for helpful comments. We also thank the participants at the July 2001 Australasian Meetings of the Econometric Society in Auckland, June 2002 University of Melbourne-National University of Singapore Symposium and seminar participants at the University of Sydney and University of New South Wales for useful suggestions. We are especially thankful to an anonymous referee whose meticulous comments have helped us to improve the paper     

The relationship between the marketing mix and share of category requirements

A criticism of purchase-based brand loyalty measures is that they are confounded by the marketing mix variables that affect brand choice. This paper investigates the magnitude and direction of the associations for share of category requirements (SCR), defined as each brand's share among the group of households who bought the brand at least once during the time period under consideration. We discuss the theoretical foundations for the relationships between SCR and a set of marketing mix variables (price, promotions, retail distribution) and conduct a latent structure regression analysis of brand-level data to test these relationships. We find that, although the relationship between the marketing mix variables and SCR is statistically significant, in real terms the magnitude of the association is fairly low.     

A covariate‐adjusted adaptive design for two‐stage clinical trials with survival data

A randomized two‐stage adaptive design is proposed and studied for allocation of patients to treatments and comparison in a phase III clinical trial with survival time as treatment responses. We consider the possibility of several covariates in the design and analysis. Several exact and limiting properties of the design and the follow‐up inference are studied, both numerically and theoretically. The applicability of the proposed methodology is illustrated by using some real data.     

The dynamics of industrial concentration in Australian manufacturing

A dynamic model of concentration is developed, with incomplete and industry-specific adjustment to deviations of concentration from its steady state. Cross-sectional analysis is carried out against a sample of 102 Australian manufacturing industries at the Australian Standard Industrial Classification (ASIC) four-digit level over the period 1977/78–1984/85. The estimated adjustment is faster than found in studies of the more mature industrial economies and this adjustment is found to significantly increase with reductions in tariff protection. There is also empirical support for John Sutton's argument that the relationship between concentration and market size depends on whether set-up costs are exogenous.     

The World Price of Insider Trading

The existence and the enforcement of insider trading laws in stock markets is a phenomenon of the 1990s. A study of the 103 countries that have stock markets reveals that insider trading laws exist in 87 of them, but enforcement—as evidenced by prosecutions—has taken place in only 38 of them. Before 1990, the respective numbers were 34 and 9. We find that the cost of equity in a country, after controlling for a number of other variables, does not change after the introduction of insider trading laws, but decreases significantly after the first prosecution.     

Applications of an inequality involving conditional expectations

The object of the present paper is to discuss some applications of an inequality involving conditional and unconditional expectations of a monotone function. The fields of application are accident statistics, personnel selection and Bessel functions.     

Migration under uncertainty about quality of locations.

"This paper develops a search-theoretic framework for analyzing migration decisions of workers who can only observe the quality of a location by migrating to the location after accepting a job there. After learning the location quality, the worker can stay at the current job, search locally at the same location, or search for a job at another location (leading to repeat migration). This paper develops the properties of optimal search, migration, and repeat migration decisions, and finds how revealed location quality influences the tradeoffs between local search and repeat migration. The effects of search costs and better job opportunities on the reservation levels of wages and revealed quality levels are also determined."