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971.
What Determines Trust in Information About Food-Related Risks? Underlying Psychological Constructs 总被引:12,自引:0,他引:12
Trust in risk information about food related-hazards may be an important determinant of public reactions to risk information. One of the central questions addressed by the risk communication literature is why some individuals and organizations are trusted as sources of risk information and others are not. Industry and government often lack public trust, whereas other sources (for example, consumer organizations, the quality media, medical doctors) are highly trusted. Problematically, previous surveys and questionnaire studies have utilized questions generated by the investigators themselves to assess public perceptions of trust in different sources. Furthermore, no account of the hazard domain was made. In the first study reported here, semistructured interviewing was used to elicit underpinning constructs determining trust and distrust in different sources providing food-related risk information ( n = 35). In the second study, the repertory grid method was used to elicit the terminology that respondents use to distinguish between different potential food-related information sources ( n = 35), the data being submitted to generalised Procrustes analysis. The results of the two studies were combined and validated in survey research ( n = 888) where factor analysis indicated that knowledge in itself does not lead to trust, but that trusted sources are seen to be characterised by multiple positive attributes. Contrary to previous research, complete freedom does not lead to trust—rather sources which possess moderate accountability are seen to be the most trusted. 相似文献
972.
Hybrid Processing of Stochastic and Subjective Uncertainty Data 总被引:1,自引:0,他引:1
Uncertainty analyses typically recognize separate stochastic and subjective sources of uncertainty, but do not systematically combine the two, although a large amount of data used in analyses is partly stochastic and partly subjective. We have developed methodology for mathematically combining stochastic and subjective sources of data uncertainty, based on new "hybrid number" approaches. The methodology can be utilized in conjunction with various traditional techniques, such as PRA (probabilistic risk assessment) and risk analysis decision support. Hybrid numbers have been previously examined as a potential method to represent combinations of stochastic and subjective information, but mathematical processing has been impeded by the requirements inherent in the structure of the numbers, e.g., there was no known way to multiply hybrids. In this paper, we will demonstrate methods for calculating with hybrid numbers that avoid the difficulties. By formulating a hybrid number as a probability distribution that is only fuzzily known, or alternatively as a random distribution of fuzzy numbers, methods are demonstrated for the full suite of arithmetic operations, permitting complex mathematical calculations. It will be shown how information about relative subjectivity (the ratio of subjective to stochastic knowledge about a particular datum) can be incorporated. Techniques are also developed for conveying uncertainty information visually, so that the stochastic and subjective components of the uncertainty, as well as the ratio of knowledge about the two, are readily apparent. The techniques demonstrated have the capability to process uncertainty information for independent, uncorrelated data, and for some types of dependent and correlated data. Example applications are suggested, illustrative problems are shown, and graphical results are given. 相似文献
973.
An environmental life cycle optimization model for the European pulp and paper industry 总被引:1,自引:0,他引:1
Will paper recycling reduce the environmental impact of the European pulp and paper sector? If so, is maximal paper recycling the best policy to optimize the life cycle of the pulp and paper sector? We explore these questions using an approach that combines materials accounting methods and optimization techniques. Environmental impact data are inputs for a linear programming network flow model to find optimal configurations for the sector. These configurations consist of a mix of different pulping technologies, a geographical distribution of pulp and paper production, and a level of recycling consistent with the lowest environmental impacts. We use the model to analyse scenarios with different recycling strategies. Recycling offers a reduction in environmental impact in regions with a high population and a large production of paper and board products. Regions with a large production of graphic products should focus on cleaner virgin pulp production with energy recovery. We conclude that relocation of paper production also offers a reduction in environmental impact. However, the severe effects on the economy make this policy less attractive than a combination of recycling, cleaner pulp production and energy recovery. 相似文献
974.
This article extends the debate begun in the June 1992 issue of EMJ when the authors first criticized Michael Porter's explanatory framework in his Competitive Advantage of Nations (1990), over the role of national culture on the competitive advantage of nations. In this paper, Frans van den Bosch and Arno van Prooijen stress that Europe is a locus of competitive advantage if one is prepared to pay attention to the possibility of ‘European Management’ as a potential asset of European firms. In this connection, the transnationalization of European firms is of importance. 相似文献
975.
AbstractThis paper explores the network synergies available from the configuration of highly dispersed, global production networks (GPNs). Synergy theory from the literature on intra-firm and inter-firm GPNs is examined in terms of drivers, mechanisms and outcomes. An explanatory model is developed and enriched via a series of extended case studies of firms undertaking re-configuration of their GPNs during the period 2003–2014. The primary finding is that firms create synergy in their GPNs by selecting specific configuration mechanisms, in response to a certain set of external drivers, in order to achieve certain synergistic outcomes. The paper classifies the main types of drivers, mechanisms and outcomes in terms of key variables and discusses their inter-connections and relationships. 相似文献
976.
The paper deals with optimal allocation of a given amount of advertising expenditure among various sales districts. It applies dynamic programming to arrive at the optimal policy regarding such allocation. The basic model is that of Zentler and Ryde which heretofore has been solved using a graphical method. The optimal solution is illustrated with an example. 相似文献
977.
The project reported in this article aimed to discover how well the needs of women were being met with respect to rural development and to identify the best approaches to communicating information to farmers in Tanzania. Semi-structured interviews of male and female respondents in selected 200 households in Shinyanga, northwestern Tanzania, were conducted. The interviews were conducted in order to record data on gender differences in farming and herding with the aim of determining how to communicate information on development. Findings showed that women continued to be the poorest group in the community. Use of introduced technology was mostly associated with men's work. The activities of Hifadhi Ardhi Shinyanga conducted through communication channels were also more accessible to men than women. The improved stoves specifically aimed at women also failed because of ineffective communication strategies. It is difficult to approach women because they tend to be tied far more closely to the area of their homes. Thus, training through village workshops would encourage the active participation of women. This would enable information to be shared with, and between, as many women as possible. 相似文献
978.
A methodological strategy for a one-number census in the UK 总被引:1,自引:1,他引:0
Brown JJ Diamond ID Chambers RL Buckner LJ Teague AD 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》1999,162(2):247-267
As a result of lessons learnt from the 1991 census, a research programme was set up to seek improvements in census methodology. Underenumeration has been placed top of the agenda in this programme, and every effort is being made to achieve as high a coverage as possible in the 2001 census. In recognition, however, that 100% coverage will never be achieved, the one-number census (ONC) project was established to measure the degree of underenumeration in the 2001 census and, if possible, to adjust fully the outputs from the census for that undercount. A key component of this adjustment process is a census coverage survey (CCS). This paper presents an overview of the ONC project, focusing on the design and analysis methodology for the CCS. It also presents results that allow the reader to evaluate the robustness of this methodology. 相似文献
979.
The article describes the technology transfer concerns reported by a small sample (N=14) of recent college graduates with disabilities. In structured, in-depth interviews, researchers asked respondents to reflect on the extent to which they had utilized technology resources during their college years in preparation for the world of work. Results suggest that colleges and universities need to play a more active role in introducing students with disabilities to both generalized and assistive technology services. 相似文献
980.