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971.
Agnieszka D. Hunka Mattia Meli Amalie Thit Annemette Palmqvist Pernille Thorbek Valery E. Forbes 《Risk analysis》2013,33(1):68-79
The article closely examines the role of mechanistic effect models (e.g., population models) in the European environmental risk assessment (ERA) of pesticides. We studied perspectives of three stakeholder groups on population modeling in ERA of pesticides. Forty‐three in‐depth, semi‐structured interviews were conducted with stakeholders from regulatory authorities, industry, and academia all over Europe. The key informant approach was employed in recruiting our participants. They were first identified as key stakeholders in the field and then sampled by means of a purposive sampling, where each stakeholder identified as important by others was interviewed and asked to suggest another potential participant for our study. Our results show that participants, although having different institutional backgrounds often presented similar perspectives and concerns about modeling. Analysis of repeating ideas and keywords revealed that all stakeholders had very high and often contradicting expectations from models. Still, all three groups expected effect models to become integrated in future ERA of pesticides. Main hopes associated with effect models were to reduce the amount of expensive and complex testing and field monitoring, both at the product development stage, and as an aid to develop mitigation measures. Our analysis suggests that, although the needs of stakeholders often overlapped, subtle differences and lack of trust hinder the process of introducing mechanistic effect models into ERA. 相似文献
972.
David Almeida Filipe Ribeiro Pedro M. Leunda Lorenzo Vilizzi Gordon H. Copp 《Risk analysis》2013,33(8):1404-1413
Risk assessments are crucial for identifying and mitigating impacts from biological invasions. The Fish Invasiveness Scoring Kit (FISK) is a risk identification (screening) tool for freshwater fishes consisting of two subject areas: biogeography/history and biology/ecology. According to the outcomes, species can be classified under particular risk categories. The aim of this study was to apply FISK to the Iberian Peninsula, a Mediterranean climate region highly important for freshwater fish conservation due to a high level of endemism. In total, 89 fish species were assessed by three independent assessors. Results from receiver operating characteristic analysis showed that FISK can discriminate reliably between noninvasive and invasive fishes for Iberia, with a threshold of 20.25, similar to those obtained in several regions around the world. Based on mean scores, no species was categorized as “low risk,” 50 species as “medium risk,” 17 as “moderately high risk,” 11 as “high risk,” and 11 as “very high risk.” The highest scoring species was goldfish Carassius auratus. Mean certainty in response was above the category “mostly certain,” ranging from tinfoil barb Barbonymus schwanenfeldii with the lowest certainty to eastern mosquitofish Gambusia holbrooki with the highest level. Pair‐wise comparison showed significant differences between one assessor and the other two on mean certainty, with these two assessors showing a high coincidence rate for the species categorization. Overall, the results suggest that FISK is a useful and viable tool for assessing risks posed by non‐native fish in the Iberian Peninsula and contributes to a “watch list” in this region. 相似文献
973.
Carl E. Cole 《Social Studies》2013,104(7):292-294
974.
John E. Angus 《统计学通讯:理论与方法》2013,42(12):4413-4419
Arnold and Strauss (1988) derived a family of bivariate life distributions having the property that the conditional distributions are exponential. Asymptotic distributions for the marginal and bivariate extremes for this family of distributions are derived employing the asymptotic theory of extreme order statistics. 相似文献
975.
976.
977.
A set of Fortran-77 subroutines is described which compute a nonparametric density estimator expressed as a Fourier series. In addition, a subroutine is given for the estimation of a cumulative distribution. Performance measures are given based on samples from a Weibull distribution. Due to small size and modest space demands, these subroutines are easily implemented on most small computers. 相似文献
978.
Decision making theory in general, and mental models in particular, associate judgment and choice. Decision choice follows
probability estimates and errors in choice derive mainly from errors in judgment. In the studies reported here we use the
Monty Hall dilemma to illustrate that judgment and choice do not always go together, and that such a dissociation can lead
to better decision-making. Specifically, we demonstrate that in certain decision problems, exceeding working memory limitations
can actually improve decision choice. We show across four experiments that increasing the number of choice alternatives forces
people to collapse choices together, resulting in better decision-making. While choice performance improves, probability judgments
do not change, thus demonstrating an important dissociation between choice and probability judgments. We propose the Collapsing
Choice Theory (CCT) which explains how working memory capacity, probability estimation, choice alternatives, judgment, and
regret all interact and effect decision quality.
相似文献
979.
The evolution of the training methods described in this paper was based on a search for relevant material, in the eyes of the student as well as the lecturer. The cornerstone of our method was to create simulations of applied situations taken from student placement experiences, and tease out both the communication elements and the central issues relating to a number of particular social work concepts. In creating explicit linkage with placement experience, the principle of student choice, in terms of identifying situations and themes appropriate for simulation, was of importance. At the same time, we would emphasize the importance of the earlier social skills and social work inputs in the course, in laying a necessary foundation for the development in the student of an ability to benefit from the broader strategy adopted in the thematic approach. 相似文献
980.