A critique of the Urban Institute's claims of cost free immigration: Early findings confirmed

This text addresses the critiques from the Urban Institute and other immigrant advocacy groups concerning the findings of an earlier study, The Cost of Immigration released in the summer of 1993. That study showed that the public costs associated withimmigrants settling here since 1970 amounted, in 1992, to $42.5 billion more in services and assistance than the $20.2 billion which immigrants paid in taxes (Huddle, 1993). The updated assessment takes into account previously unavailable figures and revises some methods and assumptions used in the earlier work. The updated bottom line is fully consistent with initial findings on immigrant costs for 1992.     

The influence of the family on premarital sexual attitudes and behavior

This research has expanded our understanding of the determinants of adolescent sexuality in several directions. We have used a study of mothers and children to construct and estimate a model of the intergenerational transmission of sexual attitudes and behavior. With data collected from both mothers and children, we were able to proceed further than most past research and to consider both the attitudes and behaviors of mothers as reported by the mothers themselves. These data permitted an investigation of the determinants of maternal attitudes concerning adolescent sexuality as well as an examination of the influences of the attitudes and experiences of mothers on the attitudes, perceptions, and behavior of children. Obviously, limiting the study to white families prevents generalization of our findings to other subgroups of the population. The findings demonstrate the importance and relevance of parental and adolescent attitudes in understanding adolescent sexuality. Premarital sexuality is a salient issue to both young people and their parents. There are, however, very important and substantial differences in the attitudes of parents and children. On average, the attitudes of young people today are much less restrictive than those of their parents, reflecting either life cycle differences or the impact of social change. The intergenerational difference is recognized by young people themselves and probably affects the ability of parents to assist their maturing children in adjusting to and dealing with their sexuality--a difficulty likely to be reflected in the relative lack of success sexually active young people have in preventing pregnancy. Our findings also add to the research literature in demonstrating that although children, on average, have more permissive attitudes than their parents, the attitudes of individual parents tend to be reflected in the attitudes of individual children. Children whose mothers have less restrictive attitudes have, on average, less restrictive attitudes themselves. Further, the attitudes of mothers are also reflected in the behavior of their children, so on average, mothers with more permissive attitudes have children who are more sexually active. The influence of maternal attitudes, however, is stronger for children's attitudes than for their behavior. Of course, variability in children's attitudes and behavior--and even their perceptions of maternal attitudes--can only be partially explained by the attitudes of their mothers; but presumably, if the attitudes of other important family members, including fathers and siblings, were known, the prediction of adolescent attitudes would improve.(ABSTRACT TRUNCATED AT 400 WORDS)     

Dealing with noncompliance and missing outcomes in a randomized trial using Bayesian technology: Prevention of perinatal sepsis clinical trial,Soweto, South Africa

The success of interventions designed to address important issues in social and medical science is best addressed by randomized experiments. With human beings there are often complications, however, such as noncompliance and missing data. Such complications are often addressed by statistically invalid methods of analysis, in particular, intention-to-treat and per-protocol analyses. Here we address these two complications using a statistically valid approach based on principal stratification with a fully Bayesian analysis. This analysis is applied to a randomized trial of a potentially important intervention designed to reduce the transmission of bacterial colonization between mothers and their infants through vaginal delivery in South Africa: the Prevention of Perinatal Sepsis (PoPs).     

Cross‐Section Regression with Common Shocks

This paper considers regression models for cross‐section data that exhibit cross‐section dependence due to common shocks, such as macroeconomic shocks. The paper analyzes the properties of least squares (LS) estimators in this context. The results of the paper allow for any form of cross‐section dependence and heterogeneity across population units. The probability limits of the LS estimators are determined, and necessary and sufficient conditions are given for consistency. The asymptotic distributions of the estimators are found to be mixed normal after recentering and scaling. The t, Wald, and F statistics are found to have asymptotic standard normal, χ², and scaled χ² distributions, respectively, under the null hypothesis when the conditions required for consistency of the parameter under test hold. However, the absolute values of t, Wald, and F statistics are found to diverge to infinity under the null hypothesis when these conditions fail. Confidence intervals exhibit similarly dichotomous behavior. Hence, common shocks are found to be innocuous in some circumstances, but quite problematic in others. Models with factor structures for errors and regressors are considered. Using the general results, conditions are determined under which consistency of the LS estimators holds and fails in models with factor structures. The results are extended to cover heterogeneous and functional factor structures in which common factors have different impacts on different population units.     

Risk preferences and changes in background risk

We present two theorems that yield necessary and sufficient conditions for first- and second-degree stochastic dominance deteriorations of background risk to increase risk aversion with respect to foreground risk. We require that any change in a foreground risk that is undesirable remains so after a background risk changes in a way that is either unfair, undesirable in the sense of reducing expected utility, or undesirable in the sense of increasing expected marginal utility. Our results thus characterize utility functions that are, respectively, vulnerable, proper, or standard with respect to changes in background risk.

The Role of Distrust in Offshore Safety Performance

Trust is recognized as a potentially important factor in safety within high-risk industries. However, little detailed empirical research has explored how trust operates in these contexts to influence worker safety performance. The present study addresses this by (i) identifying the target (occupational group) in which trust is most important for good safety, and (ii) establishing the "type" of trust (trust or distrust) with the greatest impact on safety performance. A questionnaire survey of 203 UK offshore gas workers' attitudes of trust and distrust toward four occupational groups (workmates, supervisors, offshore managers, and contractors) and an operating company was conducted. Logistic regression analysis identified attitudes toward offshore management as the strongest predictor of safety performance at an industry level. At an installation level, safety performance was best predicted by attitudes toward contractors and workmates. Further analysis revealed attitudes of distrust as better predictors of safety performance compared to attitudes of trust. These findings suggest that safety professionals should pay more attention to the role of distrust in safety performance. They also suggest that safety initiatives should target attitudes toward specific groups for optimal effectiveness.     

A cross-cultural comparison of death anxiety: a brief note

Data are reported from samples of undergraduates around the world who have been administered Templer's Death Anxiety Scale. Data from 24 American samples and from 16 nations were identified. Strong sex differences were found and an association between the scores of men and women.     

A Periodic Inventory Model for Stocking Modular Components

We study the benefit obtained by exploiting modular product design in fulfilling exogenous demand for both a complete assembly and its components in a service parts inventory system. Our goal is to reduce overall service system costs by allowing assembly and/or disassembly (A/D) to occur at some unit cost per A/D action. In an extensive set of computational experiments, we compare a naïve stocking and operating policy that treats all items independently and ignores the modular product structure and related A/D capability to the optimal base stock policy, and to a policy that allows A/D from the naïve stocking levels. While extensive computational analysis shows that the optimal base stock policy improves the system cost between 3 to 26% over the naïve approach, simply allowing A/D from the naïve stocking levels captures a significant portion (an average of 67%) of the naïve–optimal gap. Our computational results demonstrate that the optimization shifts the component‐assembly mix from the naïve levels and that limiting A/D capacity affects this mix. Limiting A/D capacity can actually increase the expected number of A/D actions (versus the uncapacitated case), since the optimization shifts stocking levels to reduce the probability that “too many” actions will be required.