An Overview of a Multimedia Benchmarking Analysis for Three Risk Assessment Models: RESRAD, MMSOILS, and MEPAS

Multimedia modelers from the United States Environmental Protection Agency (EPA) and the United States Department of Energy (DOE) collaborated to conduct a detailed and quantitative benchmarking analysis of three multimedia models. The three models—RESRAD (DOE), MMSOILS (EPA), and MEPAS (DOE)—represent analytically-based tools that are used by the respective agencies for performing human exposure and health risk assessments. The study is performed by individuals who participate directly in the ongoing design, development, and application of the models. Model form and function are compared by applying the models to a series of hypothetical problems, first isolating individual modules (e.g., atmospheric, surface water, groundwater) and then simulating multimedia-based risk resulting from contaminant release from a single source to multiple environmental media. Study results show that the models differ with respect to environmental processes included (i.e., model features) and the mathematical formulation and assumptions related to the implementation of solutions. Depending on the application, numerical estimates resulting from the models may vary over several orders-of-magnitude. On the other hand, two or more differences may offset each other such that model predictions are virtually equal. The conclusion from these results is that multimedia models are complex due to the integration of the many components of a risk assessment and this complexity must be fully appreciated during each step of the modeling process (i.e., model selection, problem conceptualization, model application, and interpretation of results).     

The motor freight industry—A case against planning

Data from 298 motor carrier firms were analyzed to determine the nature of the strategic planning function in that industry and the relationship between planning, organization size and economic performance. Generally, motor carriers were found to perform similarly irrespective of their size or commitment to strategic planning. A number of factors are suggested to explain this phenomenon.     

Actualization of Social Cognitions into Aggressive Behavior toward Disliked Targets

The basic premise that social cognitions guide behavior (aggression) was evaluated within relationships marked by dislike. At Time 1, a disliked target was identified for each participant (195 fifth‐grade children; 109 boys; 11–12 years old at Time 1) who then responded to questions about different aggression‐supporting social cognitions with regard to the chosen target. In addition, aggression directed at the identified peer (from the disliked child's perspective) was measured twice over a one‐year interval. Our results show that aggressogenic thought predicts increases in aggression only when the target is chronically disliked. Moreover, within chronically disliked relationships, the actualization of aggressogenic thought is maximized when children have high initial levels of reactive (in the case of hostile attributions) and proactive aggression (in the case of self‐efficacy beliefs), and when targets are initially high on reactive aggression. These findings suggest that social cognitions, assessed within a specific relationship context, can have more predictive validity than traditionally used decontextualized measures.     

Questions & Answeres: Reflections on Forecasting

Dedicated to the late Professor J. B. S. Haldane who brought to my attention the following very significant story from the ancient Indian epic Mahabharat (Nala—Damayanti Akhy[abar]n): The king lost his way in a jungle and was required to spend the night in a tree. The next day he told some fellow traveller that the total number of leaves on the tree were “so many”. On being challenged as to whether he counted all the leaves he replied; “No, but I counted leaves on a few branches of the tree and I know the science of die throwing”. (I can vouch for accurateness of the reproduction only in the essential respects.)     

Latent Variable Models in Heterogeneous Spaces for Observations of Mixed Types

The maximum likelihood approach to the estimation of factor analytic model parameters most commonly deals with outcomes that are assumed to be multivariate Gaussian random variables in a homogeneous input space. In many practical settings, however, many studies needing factor analytic modeling involve data that, not only are not multivariate Gaussian variables, but also come from a partitioned input space. This article introduces an extension of the maximum likelihood factor analysis that handles multivariate outcomes made up of attributes with different probability distributions, and originating from a partitioned input space. An EM Algorithm combined with Fisher Scoring is used to estimate the parameters of the derived model.     

Continuing Education as an Effective Linkage between Schools of Social Work and the Practice Community

Establishing viable linkages between social work education and practice has been a constant concern of educators and practitioners. Traditional linkages such as agency field placements and agency-based research have not materially strengthened relationships. Continuing education can be an effective linkage between schools and practitioners, providing two conditions are met. First, continuing education programs must be centrally administered as part of the mainstream of the school's curriculum. Second, both practitioners and administrators must be engaged actively in curriculum planning, implementation, and evaluation. The Extramural MSW Program and the Child Welfare Training Project at the University of Illinois at Urbana-Champaign, are used as illustrations.     

UNIVERSAL INSTRUCTIONAL DESIGN: A NEW FRAMEWORK FOR ACCOMMODATING STUDENTS IN SOCIAL WORK COURSES

Abstract

Because of shrinking budgets, college and university administrators are merging many academic units, including social work programs. By analyzing data from a 1991 survey of deans and directors of social work programs, this article compares the percentages of recently merged, long-term merged (longer than 5 years), and free-standing (independent) programs that experienced increases, decreases, and stability in variables such as salaries, financial resources, promotion and tenure, staff morale, enrollment, curriculum, class size, and access to central administration. Changes at recently merged programs are emphasized. The article also summarizes respondents' views of mergers, and recommends strategies that enable programs facing a merger to preserve their autonomy.