Contemporary Conceptions of Environmental Risk: Implications for Resource Management and Policy

Recent theoretical development in environmental sociology has focused on the concept of risk. Macro- and middle-range theoretical conceptualizations relevant to understanding environmental risk and resource depletion have emerged from Europe and the United States. We review five theoretical approaches to the environment–society relationship and identify convergent characteristics relevant for resource management in the modern world. These characteristics suggest goals for resource management should include expanded discursive systems, a more informed public and building institutional trust.     

Adolescent parenthood,economic issues,and social policies

Adolescent parenthood has highly publicized adverse social and economic consequences, but these same social and economic disadvantages can be viewed as root causes of adolescent pregnancy. Recent research and revisionist debates about these issues are reviewed and summarized. Diverse implications for social policy are considered. Prevention approaches are emphasized that build on both postponing adolescent sexual intercourse and helping sexually active teens avoid pregnancy.Appreciation is expressed to Christine Bachrach and Kristin Moore for their comments on a previous version of this paper.Dr. Miller's current research interests are the family antecedents of adolescent sexual behavior and the design and evaluation of prevention programs for adolescent problem behaviors. He received his Ph.D. in family sociology from the University of Minnesota in 1975.     

How to Compete Against a Behavioral Newsvendor

We investigate newsvendor ordering behavior under competition. We present a laboratory experiment that documents the behavioral ordering regularities in competitive newsvendor environments, and an analytical model extending the standard theory of newsvendor competition by including an optimal best‐response policy for competing with a behaviorally biased newsvendor. We test the effectiveness of this policy using an out‐of‐sample experiment and find that it results in improved market share, service level and profitability.     

Disability and going green: a comparison of the environmental values and behaviours of persons with and without disability

Some studies have suggested that socially excluded groups exhibit different environmental values and behaviours from mainstream society. To consider this in the context of disability, a survey was implemented to investigate environmental values and ecological behaviour. A high percentage of participants considered themselves to have a disability, long‐standing illness or infirmity. Over half of the sample had restricted physical mobility. The study used the revised New Ecological Paradigm Scale, a widely used measure of pro‐environmental orientation, and the General Ecological Behaviour scale to assess ecological behaviours. No significant differences were found between respondents with/without disability for either their general environmental attitudes or their general ecological behaviour. However, a positive correlation was found between level of physical mobility and general ecological behaviour. The results also show significant differences in the ecological behaviours of those respondents living dependently and those living independently; respondents living in care scored lower on the ecological behaviour scale.     

A tutorial on rank-based coefficient estimation for censored data in small- and large-scale problems

The analysis of survival endpoints subject to right-censoring is an important research area in statistics, particularly among econometricians and biostatisticians. The two most popular semiparametric models are the proportional hazards model and the accelerated failure time (AFT) model. Rank-based estimation in the AFT model is computationally challenging due to optimization of a non-smooth loss function. Previous work has shown that rank-based estimators may be written as solutions to linear programming (LP) problems. However, the size of the LP problem is O(n ²+p) subject to n ² linear constraints, where n denotes sample size and p denotes the dimension of parameters. As n and/or p increases, the feasibility of such solution in practice becomes questionable. Among data mining and statistical learning enthusiasts, there is interest in extending ordinary regression coefficient estimators for low-dimensions into high-dimensional data mining tools through regularization. Applying this recipe to rank-based coefficient estimators leads to formidable optimization problems which may be avoided through smooth approximations to non-smooth functions. We review smooth approximations and quasi-Newton methods for rank-based estimation in AFT models. The computational cost of our method is substantially smaller than the corresponding LP problem and can be applied to small- or large-scale problems similarly. The algorithm described here allows one to couple rank-based estimation for censored data with virtually any regularization and is exemplified through four case studies.     

Exposure Assessment: Then, Now, and Quantum Leaps in the Future

Health risk assessments have become so widely accepted in the United States that their conclusions are a major factor in many environmental decisions. Although the risk assessment paradigm is 10 years old, the basic risk assessment process has been used by certain regulatory agencies for nearly 40 years. Each of the four components of the paradigm has undergone significant refinements, particularly during the last 5 years. A recent step in the development of the exposure assessment component can be found in the 1992 EPA Guidelines for Exposure Assessment. Rather than assuming worst-case or hypothetical maximum exposures, these guidelines are designed to lead to an accurate characterization, making use of a number of scientific advances. Many exposure parameters have become better defined, and more sensitive techniques now exist for measuring concentrations of contaminants in the environnment. Statistical procedures for characterizing variability, using Monte Carlo or similar approaches, eliminate the need to select point estimates for all individual exposure parameters. These probabilistic models can more accurately characterize the full range of exposures that may potentially be encountered by a given population at a particular site, reducing the need to select highly conservative values to account for this form of uncertainty in the exposure estimate. Lastly, our awareness of the uncertainties in the exposure assessment as well as our knowledge as to how best to characterize them will almost certainly provide evaluations that will be more credible and, therein, more useful to risk managers. If these refinements are incorporated into future exposure assessments, it is likely that our resources will be devoted to problems that, when resolved, will yield the largest improvement in public health.     

Child Characteristics,Parenting Stress,and Parental Involvement: Fathers Versus Mothers

This study examined variations in the relationships among child characteristics, parenting stress, and parental involvement. Participants were 100 two‐parent families with preschool‐aged children. Self‐report and interview data were collected to measure parental involvement, as well as perceptions of child temperament and parental stress. Analyses revealed significant, yet somewhat different, associations between child temperament and parental stress for mothers and fathers. More significant associations were found between perceptions of child temperament and involvement for fathers than for mothers. The associations between child temperament and parental stress and involvement differed on the basis of child and parent gender. Results are discussed in terms of future research on father involvement, as well as programs designed to encourage fathers to assume more active parental roles.