On the Joint Lot-Sizing Problem with Zero Setup Costs

In a recent paper, Pinto and Mabert [5] presented a lot-sizing rule and an improvement procedure for the joint lot-sizing problem with zero setup costs. We show that this procedure often yields infeasible schedules. We also present and discuss two interesting properties of the joint lot-sizing problem with zero setup costs. A numerical example to illustrate the second property is provided.     

Data Driven Modeling: An Application in Scheduling

This paper presents a data driven modeling (DDM) approach to certain types of optimization problems. DDM relinquishes control of the completed model to the user department rather than the operations research (OR) staff. The approach emphasizes development of models that are dependent on data maintained and understood by the users. The data base consists of coded user rules which describe when changes will occur in the problem structure and data which captures the generalization of the problem. Both the rules and data can be updated by user department personnel. These data drive a matrix generator controlled by the rules which uses the data base as input to generate the specific model formulation. This DDM system is designed by OR consultants or staff to allow independence of use along with low-cost and minimal-effort maintenance. The DDM approach is illustrated with an application to a real-world medical scheduling problem.     

Social Background Differences in Early Family Behavior

Social background has historically been recognized as a major factor influencing family behavior, though recent work has largely emphasized racial/ethnic influences. Here we use 1994 – 1995 and 2001 – 2002 Add Health data to examine the cohabitation, first marriage, and first birth experience of young women. In a multistate life table context, hypothetical cohorts specified in terms of race and mother’s education are followed, from age 11 to age 24, as they move through 6 family‐related statuses. The results indicate that, for both Black and White women, a higher level of maternal education is generally associated with less cohabitation, less marriage, fewer first births, and a higher percentage of women who experience none of those transitions before age 24. Racial and social background differences are conceptually and empirically distinct. Because mother’s education is associated with substantially different trajectories of early family behavior for both Blacks and Whites, we argue that social background merits increased attention in research on contemporary American family patterns.     

A framework for the comparison of maximum pseudo-likelihood and maximum likelihood estimation of exponential family random graph models

The statistical modeling of social network data is difficult due to the complex dependence structure of the tie variables. Statistical exponential families of distributions provide a flexible way to model such dependence. They enable the statistical characteristics of the network to be encapsulated within an exponential family random graph (ERG) model. For a long time, however, likelihood-based estimation was only feasible for ERG models assuming dyad independence. For more realistic and complex models inference has been based on the pseudo-likelihood. Recent advances in computational methods have made likelihood-based inference practical, and comparison of the different estimators possible.     

Former Minister Zhang's discourse on SARS: Government's image restoration or destruction?

This study analyzes the image repair discourse by Chinese Health Minister Zhang Wenkang's discourse on SARS. The minister faced several accusations: the SARS outbreak was growing, the Chinese government had covered up the severity of this problem, the Chinese government ignored Taiwanese who suffered from SARS, and the Health Ministry provided information that was neither timely nor accurate. He employed several image repair strategies (denial, defeasibility, bolstering, minimization, differentiation, attack accuser, and corrective action). However, his messages were contradictory and apparently related on false information, so his efforts were unsuccessful and he was stripped of his office.     

The roles of human capital and social capital in the economic integration of new arrivals from Mainland China to Hong Kong

Although it has been hypothesized in the literature that both human capital and social capital are important for the economic performance of new immigrants, few studies have examined these relationships empirically, especially in understudied populations such as Chinese populations. This study simultaneously examines the roles of human capital and social capital in the economic integration of new arrivals from Mainland China to Hong Kong, using a random sample of immigrants. In the early stage of immigration (less than 6 months after arrival), we find little support for the presumed positive effects of both human capital and social capital on employment status among new arrivals in Hong Kong. Follow-up studies are underway to investigate the dynamic relationship between social capital and economic integration in this group of new arrivals, and whether social capital, especially friendship networks, plays a more important role in the economic integration of new immigrants 1 or 2 years after arrival.     

Adolescent Deliberate Self‐Harm: Linkages to Emotion Regulation and Family Emotional Climate

Parents' responses to their children's emotional expressivity have been shown to significantly influence children's subsequent psychosocial functioning. This study hypothesized that adolescents' deliberate self‐harm (DSH) may be an outcome associated with poor emotion regulation as well as an invalidating family environment. The mediational role of specific emotion processes (i.e., poor awareness of emotion, difficulties expressing emotions) between family emotional environment and the frequency of DSH was examined with 131 psychiatrically hospitalized adolescents (M age=14.84 years, SD=1.75 years). Results indicated that adolescents who self‐injured reported that this behavior reduced their negative emotional states. Structural equation modeling provided support for the proposed model that family climate influences frequency of DSH through emotion regulation skills but the model held for girls only. A direct model effect was not supported. Emotion regulation partially mediated the relationship between family climate and DSH, and direct effects were also observed.     

Some indications of limits to framing the policy preferences of the civically engaged: Interplay of social capital,race attitudes,and social justice frames

Our experiment, which tested support for a hypothetical social welfare program, found that the civically engaged as a whole were resistant to social justice framing employing universalistic versus particularistic standards. We suggest the lack of a framing effect was due to the use of a preexisting, shared “symbolic racism” frame. Social justice framing did succeed for those whose attitudes toward symbolic racism were ambivalent or neutral. Other factors including sex, income level, political participation, and ideology significantly influenced choice. These results provide some indications of limits to experimental framing of policy preferences of the civically engaged in their institutional settings.     

An Exploratory Study of Financial Remittances Among Non-Resident Indians in the United States

Remittances by immigrants and temporary workers of Indian origin in industrialized countries are a growing part of India’s economy. In this exploratory study we examine the social and economic characteristics affecting the remittance pattern of working households (or families) of Indian origin residing in the United States. As most previous studies have been undertaken at the macroeconomic level, our main contribution lies in identifying the household level factors that may influence remittances. Using an online and a mail-in survey of 39 households we find some of the significant factors affecting remittances. We also validate some of the remittance-related policies of the Indian government.