Microstructural analysis in interorganizational systems

This paper argues that network analyses of interorganizational relations should begin by examining the way in which relations are organized at the local level. It posits that systematic departures from random models for dyad and triad censuses should be found before interpreting structural patterns isolated by analytic techniques concerned with overall network structure. Three principles of organizational bonding (resource inequality, reciprocity, and redundancy) are identified, and the implications of these for dyadic and triadic microstructures are detailed. Particular attention is given to differentiating between microstructural patterns to be anticipated when a system consists of autonomous actors approximately equal in power and resources and those expected when a system is highly centralized.     

Legal and policy implications of the flexible employment relationship

V. Conclusion The flexible employment relationship encompassing as it does so many different kinds of arrangements — temporary, leased, homeworking, telecommuting, jobsharing, and consulting workers — is not a good candidate for the kinds of across-the-board regulatory proposals that are presently popular. Although the negatives of involuntary contingent employment receive considerable attention (relatively lower wages, the absence of access to benefit plans), the advantages (mutual flexibility and the opportunity to transmit/receive training and experience) do not. Proposals to raise the relative cost of employing contingent workers need to address each of the following three concerns: First, the mix of “employees” and independent contractors some of whom voluntarily fill the ranks of contingent workers; second, the absence of any meaningful job protections or legal claims to nonmandated benefits by mostcore workers; and, finally, the possibility that in some cases contingent workers’ wages operate asde facto sub-minimum training wage. More empirical work is needed in order to evaluate each of these issues. In the meantime, a case has yet to be made for altering the existing regulatory framework facing employers of flexible workers. I am indebted to Joseph Salama for research assistance and to Michael Harper, Keith N. Hylton, Stephen Marks, and Larry Yackle for helpful comments.     

Multivariate distributions with generalized inverse gaussian marginals,and associated poisson mixtures

Several types of multivariate extensions of the inverse Gaussian (IG) distribution and the reciprocal inverse Gaussian (RIG) distribution are proposed. Some of these types are obtained as random-additive-effect models by means of well-known convolution properties of the IG and RIG distributions, and they have one-dimensional IG or RIG marginals. They are used to define a flexible class of multivariate Poisson mixtures.     

Statistical issues in epidemiologic studies of the health effects of ambient acid aerosols

Although the ecologic effects of acid rain have been widely reported, relatively little is known about the effects of acidic air pollution on human health. Some epidemiologic and animal studies suggest, however, that acidity is an important determinant of the respiratory health effects of aerosols. This paper reviews some of that evidence and discusses its implications for the design and analysis of epidemiologic studies. We contrast two types of exposure patterns: peak exposures associated with air pollution episodes, and chronic exposures resulting from persistently high levels of air pollutants. Recent work on the analysis of repeated categorical outcome variables provides new methods for the analysis of episode studies. Studies of long-term exposure require comparisons among population groups, and these comparisons can be subject to the design effects characteristic of multistage sample surveys. We examine the implications of these design effects for epidemiologic studies. Finally, the paper discusses the measurement errors induced by the use of outdoor measurements to quantify personal exposure to air pollutants. Recent work on methods for errors-in-variables problems may aid in assessing the effects of such errors on conventional analyses of air-pollution studies.     

New evidence on the value of birth expectations

Past national surveys regarding birth expectations have usually been restricted to currently married women, a fact which has led demographers to question the usefulness of these data. Because the June 1976 Current Population Survey includes the expectations of all women in a cohort regardless of marital status, it provides the data needed to evaluate biases due to restricted survey universes. At older ages, where there are substantial differences in lifetime expectations between currently married and single women, there are relatively few single women; at younger ages, however, where the proportion of single women in a cohort is relatively large, the differences in expectations are small. This counterbalancing effect makes the lifetime birth expectations of currently married women a close approximation of all women in a cohort. The analysis also indicates that the observed intracohort declines in lifetime birth expectations since 1967 were due largely to the addition at subsequent survey dates of previously unmarried women; nevertheless, some “true” cohort declines also seem to have occurred.     

FLUCTUATING EXCHANGE RATES AND THE PRICING OF EXPORTS

The purpose of this paper is to examine the invoicing decision of an exporter under a system of pegged exchange rates and a system of freely fluctuating rates. With pegged exchange rates, the exporter may equivalently invoice in its home currency or in the currency of its foreign clients, since the two prices are related by the pegged rate. With fluctuating rates, however, the choice of an invoicing strategy is important and will affect the level of trade. The optimal prices with each strategy are compared, and the exporter's responses to governmental policy instruments are characterized.