Multimedia Benchmarking Analysis for Three Risk Assessment Models: RESRAD, MMSOILS, and MEPAS

This paper is one in a series that describes results of a benchmarking analysis initiated by the Department of Energy (DOE) and the United States Environmental Protection Agency (EPA). An overview of the study is provided in a companion paper by Laniak et al. presented in this journal issue. The three models used in the study—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. Both single media and multimedia benchmarking scenarios were developed and executed. In this paper, the multimedia scenario is examined. That scenario consists of a hypothetical landfill that initially contained uranium-238 and methylene chloride. The multimedia models predict the fate of these contaminants, plus the progeny of uranium-238, through the unsaturated zone, saturated zone, surface water, and atmosphere. Carcinogenic risks are calculated from exposure to the contaminants via multiple pathways. Results of the tests show that differences in model endpoint estimates arise from both differences in the models' mathematical formulations and assumptions related to the implementation of the scenarios.     

Bandwidth sums of block graphs and cacti

A labeling of a graph G is an injective function f:V(G)→?. The bandwidth sum of a graph G with respect to a labeling f is $B_{s}^{f}(G) = \sum_{uv \in E(G)} |f(u)-f(v)|$ and the bandwidth sum of G is $B_{s}(G) = \min\{B_{s}^{f}(G)\colon f\mbox{ is a labeling of }G\}$ . In this paper, we determine bandwidth sums for some block graphs and cacti.     

Can Latin America carry its international debt? A prospective analysis using the Wharton Latin American debt simulation model

The international debt of the LDCs has become a critical concern, perhaps currently the most critical one, from the perspective of debtor countries and creditors alike. Through the efforts of the IMF, the BIS, the central banks, and the large commercial banks, a crash may have averted for the time being, but the heavy burden of the debt remains, particularly in Latin America, where it is increasingly concentrated. Draconian remedial measures now threaten social and economic development throughout the continent.This article evaluates the perspective for Latin American debts and payments using a debt simulation model. Debt restructuring with the usual “IMF conditions” will impose serious economic shocks in Latin America. But even so, debt service ratios will remain high except under optimistic assumptions about growth in the industrial countries and about commodity prices. Only in case of a solid economic recovery in the United States, Europe and Japan can one be sanguine about Latin America's ability to work its way out from under the debt burden.     

EXPOSING ADOPTION MYTHS: ACCESS TO INFORMATION ABOUT ORIGINS IN VICTORIA

Victoria was the first State to allow adopted persons unqualified access to their original identity and to provide natural parents and others with conditional access to identifying information. This article examines findings from 1985 to 1988 to examine four assumptions. These are that: few adoptees would want to know about or meet their natural parents and so few would register with the Adoption Information Service; few adoptees would welcome an approach from or on behalf of their natural parents and most would reject such an approach; few relinquishing parents would wish to meet or know about their relinquished child and consequently most would reject an approach by or on behalf of their child; and adoptive parents would not wish to acknowledge the adoptive status of their children by providing information to the natural parent facilitating a meeting between the natural parent and the child. The data suggest that the above assumptions do not reflect the experience or behaviour of adopted persons, natural parents or adoptive parents.     

Towards Common Ground and Trading Zones in Management Research and Practice

The purpose and nature of management scholarship is contested, evidenced by debates about the ‘academic–practitioner divide’ and attendant remedies for addressing it, including mode 2 and mode 3 research, engaged scholarship, evidence‐based management and design science. In this paper the authors argue that, without a culture of dialogical encounter, management scholarship will never be able to emerge from its adolescence, and management will not develop into the profession that it should and can become. The central proposition is that the highly fragmented landscape of management (practice and scholarship) lacks sufficient capability for dialogue among the plurality of actors situated across that landscape. Developing the dialogical capability ultimately required to break this fundamental impasse demands, first, a shared sense of purpose and responsibility (akin to the Hippocratic Oath in medicine) and, second, institutional entrepreneurship to establish more and better ‘trading zones’. Drawing on the philosophy of pragmatism, the authors further this endeavour by identifying and proposing key elements of a statement of shared purpose and responsibility. Finally, they explore the nature and characteristics of successful trading zones, highlighting particular examples that have already been created in management studies.     

Off to Plan or Out to Lunch? Relationships between Design Characteristics and Outcomes of Strategy Workshops

Strategy workshops, also known as away days, strategy retreats and strategic ‘off‐sites’, have become widespread in organizations. However, there is a shortage of theory and evidence concerning the outcomes of these events and the factors that contribute to their effectiveness. Adopting a design science approach, in this paper we propose and test a multidimensional model that differentiates the effects of strategy workshops in terms of organizational, interpersonal and cognitive outcomes. Analysing survey data on over 650 workshops, we demonstrate that varying combinations of four basic design characteristics – clarity of goals and purpose, routinization, stakeholder involvement and cognitive effort – predict differentially these three distinct types of outcomes. Calling into question conventional wisdom on the design of workshops, we discuss the implications of our findings for integrating further the strategy process, strategy‐as‐practice and strategic cognition literatures, to enrich understanding of the factors that shape the nature and influence of contemporary strategic planning activities more generally.     

MEASURING LABOR MARKET FRICTIONS: A CROSS‐COUNTRY COMPARISON

In this paper we define and estimate measures of labor market frictions using data on job durations. We compare different estimation methods and different types of data. We propose and apply an unconditional inference method that can be applied to aggregate duration data. It does not require wage data, it is invariant to the way in which wages are determined, and it allows workers to care about other job characteristics. The empirical analysis focuses on France, but we perform separate analyses for the United States of America, the United Kingdom, Germany, and the Netherlands. We quantify the monopsony power due to search frictions and we examine the policy effects of the minimum wage, unemployment benefits, and search frictions. (JEL: J63, J64)     

The Nonparametric Identification of Treatment Effects in Duration Models

This paper analyzes the specification and identification of causal multivariate duration models. We focus on the case in which one duration concerns the point in time a treatment is initiated and we are interested in the effect of this treatment on some outcome duration. We define “no anticipation of treatment” and relate it to a common assumption in biostatistics. We show that (i) no anticipation and (ii) randomized treatment assignment can be imposed without restricting the observational data. We impose (i) but not (ii) and prove identification of models that impose some structure. We allow for dependent unobserved heterogeneity and we do not exploit exclusion restrictions on covariates. We provide results for both single‐spell and multiple‐spell data. The timing of events conveys useful information on the treatment effect.     

CRITICAL PERIODS DURING CHILDHOOD AND ADOLESCENCE

We identify the ages that constitute sensitive (or critical) periods in children's development towards their adult health status, skills, and human capital. For this, we use data on families migrating into Sweden from countries that are poorer, with less healthy conditions. Late‐life health is proxied by adult height and other adult outcomes. The relation between siblings’ ages at migration and their adult outcomes allows us to estimate the causal effect of conditions at specific childhood ages. We effectively exploit that, for siblings, the migration occurs simultaneously in calendar time but at different developmental stages (ages). We find evidence that the period just before the puberty growth spurt constitutes a critical period for adult height and we find related critical periods for adult cognition, mental health, and education.     

Informing employees in small and medium-sized firms about training: Results of a randomized field experiment

We mailed brochures to 10,000 randomly chosen employed German workers who were eligible for a subsidized occupational training program called WeGebAU, informing them about the importance of skills-upgrading training in general and about WeGebAU in particular. Using survey and register data, we estimate effects of the informational brochure on awareness of the program, on take-up of WeGebAU and other training, and on subsequent employment. The brochure more than doubles awareness of the program. There are no effects on WeGebAU take-up, but participation in other (unsubsidized) training increases among employees aged under 45. Short-term labor market outcomes are not affected.