Organizations enter alliances with each other to access critical resources, but they rely on information from the network of prior alliances to determine with whom to cooperate. These new alliances modify the existing network, prompting an endogenous dynamic between organizational action and network structure that drives the emergence of interorganizational networks. Testing these ideas on alliances formed in three industries over nine years, the authors show that the probability of a new alliance between specific organizations increases with their interdependence, but also with their prior mutual alliances, common third parties, and joint centrality in the alliance network. The differentiation of the emerging network structure, however, mitigates the effect of interdependence and enhances the effect of joint centrality on new alliance formation. 3

A great deal of controversy exists about the impact of information technology on firm performance. While some authors have reported positive impacts, others have found negative or no impacts. This study focuses on Electronic Data Interchange (EDI) technology. Many of the problems in this line of research are overcome in this study by conducting a careful analysis of the performance data of the past decade gathered from the assembly centers of Chrysler Corporation. This study estimates the dollar benefits of improved information exchanges between Chrysler and its suppliers that result from using EDI. After controlling for variations in operational complexity arising from mix, volume, parts complexity, model, and engineering changes, the savings per vehicle that result from improved information exchanges are estimated to be about $60. Including the additional savings from electronic document preparation and transmission, the total benefits of EDI per vehicle amount to over $100. System wide, this translates to annual savings of $220 million for the company.

Traditionally and understandably, the microscope of market microstructure has focused on attributes of single assets. Little theoretical attention and virtually no empirical work has been devoted to common determinants of liquidity nor to their empirical manifestation, correlated movements in liquidity. But a wider-angle lens exposes an imposing image of commonality. Quoted spreads, quoted depth, and effective spreads co-move with market- and industry-wide liquidity. After controlling for wellknown individual liquidity determinants, such as volatility, volume, and price, common influences remain signi"cant and material. Recognizing the existence of commonality is a key to uncovering some suggestive evidence that inventory risks and asymmetric information both affect intertemporal changes in liquidity.

This study uses data from a representative survey of households with preschoolers in Accra, Ghana to (1) examine the importance of care practices for children's height-forage z-scores (HAZ); and (2) identify subgroups of children for whom good maternal care practices may be particularly important. Good caregiving practices related to child feeding and use of preventive health services were a strong determinant of children's HAZ, specially among children from the two lower income terciles and children whose mothers had less than secondary schooling. In this population, good care practices could compensate for the negative effects of poverty and low maternal schooling on children's HAZ. Thus, effective targeting of specific education messages to improve child feeding practices and use of preventive health care could have a major impact on reducing childhood malnutrition in Accra. CONTENTS Acknowledgments .................................................... vii 1. Introduction ............

this report. Willis was a pioneer in the economic analysis of agricultural research and technical change, a teacher, and an inspiration---as well as a friend and a good bloke

Firms are undertaking growing numbers of e-commerce initiatives and increasingly making significant investments required to participate in the growing online market. However, empirical support for the benefits to firms from e-commerce is weaker than glowing accounts in the popular press, based on anecdotal evidence, would lead us to believe. In this paper, we explore the following questions: What are the returns to shareholders in firms engaging in e-commerce? How do the returns to conventional, brick and mortar firms from e-commerce initiatives compare with returns to the new breed of net firms? How do returns from businessto-business e-commerce compare with returns from business-to-consumer e-commerce? How do the returns to e-commerce initiatives involving digital goods compare to initiatives involving tangible goods? We examine these issues using event study methodology and assess the cumulative abnormal returns to shareholders (CARs) for 251 e-commerce initiatives announced by firms between October and December 1998. The results suggest that e-commerce initiatives do indeed lead to significant positive CARs for firms ’ shareholders. While the CARs for conventional firms are not significantly different from those for net firms, the CARs for businessto-consumer (B2C) announcements are higher than those for business-to-business (B2B) announcements.

The structure of a fitness landscape is still an ill-defined concept. This paper introduces a statistical fitness landscape analysis, that can be used on a multitude of fitness landscapes. The result of this analysis is a statistical model that, together with some statistics denoting the explanatory and predictive value of this model, can serve as a measure for the structure of the landscape. The analysis is based on a statistical time series analysis known as the Box-Jenkins approach, that, among others, estimates the autocorrelations of a time series of fitness values generated by a random walk on the landscape. From these estimates, a correlation length for the landscape can be derived. Keywords: Fitness landscapes, Correlation structure, Correlation length 1 Introduction "We need a real theory relating the structure of rugged multipeaked fitness landscapes to the flow of a population upon those landscapes. We do not yet have such a theory." This quote, from Stuart A. Kauffman [...

economics at the University of Chicago

Abstract not found

TMD Discussion Papers contain preliminary material and research results, and are circulated prior to a full peer review in order to stimulate discussion and critical comment. It is expected that most Discussion Papers will eventually be published in some other form, and that their content may also be revised. This paper is available at