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91.
Various methods have been proposed for evaluating the importance of an independent variable in determining a given dependent variable. This paper suggests that the analysis of direct and indirect effects in a recursive causal model can provide a more satisfactory evaluation than the ordinary correlation and regression techniques commonly used. The interpretation of an independent variable's impact derived from a path model is generally more adequate because it is able to take into account the operation of indirect effects and spuriousness. To demonstrate this contention, data gathered by the author to explain organizational innovation are presented.  相似文献   
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A challenge for large‐scale environmental health investigations such as the National Children's Study (NCS), is characterizing exposures to multiple, co‐occurring chemical agents with varying spatiotemporal concentrations and consequences modulated by biochemical, physiological, behavioral, socioeconomic, and environmental factors. Such investigations can benefit from systematic retrieval, analysis, and integration of diverse extant information on both contaminant patterns and exposure‐relevant factors. This requires development, evaluation, and deployment of informatics methods that support flexible access and analysis of multiattribute data across multiple spatiotemporal scales. A new “Tiered Exposure Ranking” (TiER) framework, developed to support various aspects of risk‐relevant exposure characterization, is described here, with examples demonstrating its application to the NCS. TiER utilizes advances in informatics computational methods, extant database content and availability, and integrative environmental/exposure/biological modeling to support both “discovery‐driven” and “hypothesis‐driven” analyses. “Tier 1” applications focus on “exposomic” pattern recognition for extracting information from multidimensional data sets, whereas second and higher tier applications utilize mechanistic models to develop risk‐relevant exposure metrics for populations and individuals. In this article, “tier 1” applications of TiER explore identification of potentially causative associations among risk factors, for prioritizing further studies, by considering publicly available demographic/socioeconomic, behavioral, and environmental data in relation to two health endpoints (preterm birth and low birth weight). A “tier 2” application develops estimates of pollutant mixture inhalation exposure indices for NCS counties, formulated to support risk characterization for these endpoints. Applications of TiER demonstrate the feasibility of developing risk‐relevant exposure characterizations for pollutants using extant environmental and demographic/socioeconomic data.  相似文献   
94.
In recent years there has been a marked increase in the study of the influence of leadership on creativity, and the effects of this relationship on organizational performance. While a number of explanations have been broached with regard to the positive effects of leadership on creativity, many of these studies propose different, and often contradictory, methods for leaders to achieve these positive effects on creativity within their organizations and work groups. Additionally, little work has been done examining the effects of leadership on highly creative people in fields requiring creativity. The purpose of this study is to examine two existing leadership theories with regard to their viability as models to explain creative performance of eminent scientists. Eminent scientists represent a population of leaders of highly creative individuals in a field that values the production of innovative ideas and products as a marker of performance. Ninety-three excerpts from the biographies of scientists were content coded for leader behaviors and performance criteria. The results of this analysis indicate that a model based on strategic planning and product championing may serve to explain the positive effects of leadership on creativity in a highly creative population.  相似文献   
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ABSTRACT

The concept of “policy advisory systems” was introduced by Halligan in 1995 as a way to characterize and analyze the multiple sources of policy advice utilized by governments in policy-making processes. The concept has proved useful and has influenced thinking about both the nature of policy work in different advisory venues as well as how these systems change over time. However, to date this work has examined mainly cases of developed countries and its application to developing and transitional countries is less certain. This paper sets out existing models of policy advisory systems based on Halligan’s original thinking on the subject and assesses the findings of many existing studies into OECD countries that advisory systems have been changing as a result of the dual effects of increased use of external consultants and others sources of advice – “externalization” – and the increased use of partisan advice inside government itself – “politicization”. Determining whether or not such changes have also characterized the situations found in developing and transitional countries and at the international-domestic and state-sub-state levels is the subject of the papers in this Special Issue.  相似文献   
96.

Skinner (1957) differentiated the roles of the speaker and the listener in a verbal encounter. Although not extensively emphasized, Skinner suggested an individual often behaves verbally even when responding as a listener. Children diagnosed with autism spectrum disorders (ASD) often display the absence of important, and basic verbal repertoires that limit their ability to engage in a variety of social skills or problem-solving skills. Joint control suggests that multiply controlled verbal responding involves functional control of two 2 or more stimuli or verbal operants. This systematic literature review provides a summary of publications specifying the relation and implications of the analysis of joint control and joint control training in the acquisition of multiply controlled, non-speaker behaviors (e.g., selection-based behavior; , sequencing behavior). The synthesis suggests that joint control training presents as a promising analytic tool in guiding interventions to teach complex, multiply controlled verbal and non-verbal repertoires to children diagnosed with autism ASD and/or other developmental disabilities. Recommendations for future research in joint control, as well as the implementation of joint control training, are provided.

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97.
ABSTRACT

Adaptation to climate change is emerging as a central objective and policy frame for coastal communities. This paper examines recent climate change adaptation efforts in the UK, centring on the case of Fairbourne, Wales. The village is facing the long-term prospect of flooding and inundation due to the impacts of sea level rise. The recent Shoreline Management Plan for the area has recommended realignment of the coast and eventual decommissioning of Fairbourne. The paper draws on a qualitative research methodology of interviews, policy review and observation to narrate the case and provide key insights and lessons for planners working in environmentally vulnerable coastal settings and managing climate adaptation processes.  相似文献   
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In this paper we compare several types of economic dependency ratios for a selection of European countries. These dependency ratios take into account not only the demographic structure of the population, but also the differences in age-specific economic behaviour such as labour market activity, income and consumption as well as age-specific public transfers. In selected simulations where we combine patterns of age-specific economic behaviour and transfers with population projections, we show that in all countries population ageing would lead to a pronounced increase in dependency ratios if present age-specific patterns were not to change. Our analysis of cross-country differences in economic dependency demonstrates that these differences are driven by both differences in age-specific economic behaviour and in the age composition of the populations. The choice of which dependency ratio to use in a specific policy context is determined by the nature of the question to be answered. The comparison of our various dependency ratios across countries gives insights into which strategies might be effective in mitigating the expected increase in economic dependency due to demographic change.  相似文献   
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