e‐Integration in the Supply Chain: Barriers and Performance*

Current opinion holds that Internet‐based supply chain integration with upstream suppliers and downstream customers (called “e‐integration” in this paper) is superior to traditional ways of doing business. This proposition remains untested, however, and similarly we know little about what are the upstream, internal, and downstream barriers to implementing e‐integration. This paper empirically addressed these questions using data from a large single nation study, and found (1) a positive link between e‐integration and performance, and (2) that internal barriers impeded e‐integration more than either upstream supplier barriers or downstream customer barriers. Findings from this study contribute to our theoretical understanding of implementing change in contemporary supply chains, and have important implications for manufacturers interested in improving their supply chain's performance using the Internet.     

Flow Coordination and Information Sharing in Supply Chains: Review,Implications, and Directions for Future Research

Advances in information technology, particularly in the e‐business arena, are enabling firms to rethink their supply chain strategies and explore new avenues for inter‐organizational cooperation. However, an incomplete understanding of the value of information sharing and physical flow coordination hinder these efforts. This research attempts to help fill these gaps by surveying prior research in the area, categorized in terms of information sharing and flow coordination. We conclude by highlighting gaps in the current body of knowledge and identifying promising areas for future research.     

AN IMPROVED HEURISTIC FOR STAFFING TELEPHONE CALL CENTERS WITH LIMITED OPERATING HOURS

Many telephone call centers that experience cyclic and random customer demand adjust their staffing over the day in an attempt to provide a consistent target level of customer service. The standard and widely used staffing method, which we call the stationary independent period by period (SIPP) approach, divides the workday into planning periods and uses a series of stationary independent Erlang‐c queuing models—one for each planning period—to estimate minimum staffing needs. Our research evaluates and improves upon this commonly used heuristic for those telephone call centers with limited hours of operation during the workday. We show that the SIPP approach often suggests staffing that is substantially too low to achieve the targeted customer service levels (probability of customer delay) during critical periods. The major reasons for SIPP‘ s shortfall are as follows: (1) SIPP's failure to account for the time lag between the peak in customer demand and when system congestion actually peaks; and (2) SIPP’ s use of the planning period average arrival rate, thereby assuming that the arrival rate is constant during the period. We identify specific domains for which SIPP tends to suggest inadequate staffing. Based on an analysis of the factors that influence the magnitude of the lag in infinite server systems that start empty and idle, we propose and test two simple “lagged” SIPP modifications that, in most situations, consistently achieve the service target with only modest increases in staffing.     

The Time Series and Cross‐Section Asymptotics of Dynamic Panel Data Estimators

In this paper we derive the asymptotic properties of within groups (WG), GMM, and LIML estimators for an autoregressive model with random effects when both T and N tend to infinity. GMM and LIML are consistent and asymptotically equivalent to the WG estimator. When T/N→ 0 the fixed T results for GMM and LIML remain valid, but WG, although consistent, has an asymptotic bias in its asymptotic distribution. When T/N tends to a positive constant, the WG, GMM, and LIML estimators exhibit negative asymptotic biases of order 1/T, 1/N, and 1/(2N−T), respectively. In addition, the crude GMM estimator that neglects the autocorrelation in first differenced errors is inconsistent as T/N→c>0, despite being consistent for fixed T. Finally, we discuss the properties of a random effects pseudo MLE with unrestricted initial conditions when both T and N tend to infinity.     

The Singularity of the Information Matrix of the Mixed Proportional Hazard Model

This paper presents new identification conditions for the mixed proportional hazard model. In particular, the baseline hazard is assumed to be bounded away from 0 and ∞ near t = 0. These conditions ensure that the information matrix is nonsingular. The paper also presents an estimator for the mixed proportional hazard model that converges at rate N^−1/2.     

A case study of failure to thrive and inter‐agency work

Social workers and medical professionals have an ambiguous relationship. Though expected to work together within the child protection regulations of the Children Act 1989, there are many tensions. In general, social workers and health visitors enjoy close working relationships, but tensions are frequently experienced as one proceeds higher up the medical hierarchy. The reasons for this may be numerous, but in practice may obstruct speedy action in detection and prevention of disease which is social in aetiology — yet all professionals have an important role. I hope to demonstrate this in the following case study, where ‘failure to thrive’ took 18 months to evidence but, without inter‐agency working, might have proved fatal to the child. Copyright © 2000 John Wiley & Sons, Ltd.     

Gender Asymmetry in Family Migration: Occupational Inequality or Interspousal Comparative Advantage?

This paper examines gender inequality in the determinants of job‐related long‐distance migration among married dual‐earner couples during the 1980s and 1990s. The analysis tested the structural explanation, which attributes gender asymmetry in family migration to structural inequality in the labor market, and the comparative advantage explanation derived from relative resource theory. The analysis used individual‐ and family‐level data from 5,504 Panel Study of Income Dynamics families, occupation‐level data from the 1980–2000 U.S. Decennial Censuses Integrated Public Use Micro Samples, and discrete‐time event history models. Gender differences in the determinants of family migration were not explained by gender differences in occupational characteristics, but the results partially support the relative resource theory by illustrating the conditioning influence of interspousal comparative advantage.     

Poverty and the American Family: A Decade in Review

Because of dramatic levels of economic volatility and massive changes in welfare policies, scholars in this decade worried anew about whether our official poverty measure, adopted in the 1960s, is adequate. Poverty's causes continued to be debated, with demographic factors often pitted against policy and maternal employment changes. Some scholars focused on events that trigger spirals into poverty or poverty exits. The literature on consequences of poverty featured new techniques for identifying underlying processes and mechanisms. Researchers also explored “neighborhood effects” and focused on poverty deconcentration efforts. Finally, scholars produced a voluminous literature on the efforts to reform welfare and their subsequent effects.     

Socioeconomic Status,Family Processes,and Individual Development

Research during the past decade shows that social class or socioeconomic status (SES) is related to satisfaction and stability in romantic unions, the quality of parent‐child relationships, and a range of developmental outcomes for adults and children. This review focuses on evidence regarding potential mechanisms proposed to account for these associations. Research findings reported during the past decade demonstrate support for an interactionist model of the relationship between SES and family life, which incorporates assumptions from both the social causation and social selection perspectives. This review concludes with recommendations for future research on SES, family processes, and individual development in terms of important theoretical and methodological issues yet to be addressed.     

Biosocial Influences on the Family: A Decade Review

The past decade brought a remarkable increase in the number and quality of biosocial studies of family processes. The current review summarizes recent advances in biosocial family research by providing key exemplars of emerging research paradigms. Research in the past decade has substantiated the claim in the previous Decade Review ( Booth, Carver, & Granger, 2000 ) that bidirectional influences between all levels of analysis are paramount. There is an emerging consensus that integrating factors at multiple biological and social levels is highly informative. Because ignoring biological factors often will underestimate mediating or moderating mechanisms, the review provides recommendations for biosocial family research. We also highlight the need for researchers who understand complex family environments to lend their expertise to biosocial studies.