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311.
This study, based on quantitative and qualitative surveys conducted from July 2004 to September 2005, examines the perceptions of Hanoi consumers and their reactions to the Avian Influenza epizootic (H5N1). Hanoi consumers clearly link the risk of human contamination by the virus to the preparation and ingestion of poultry. During the first crisis, consumers reacted quickly and intensely (74% of them had already stopped eating poultry in January 2004). Nevertheless, once the crisis abated, they quickly resumed their consumption of poultry. This behavior corresponds to the pattern described by empirical studies of other crises, such as BSE. What is more surprising is the speed with which the different steps of this common pattern succeeded one another. It may be explained by a rapid decrease in risk anxiety. A logit model shows that, soon after the beginning of the crisis, AI risk anxiety was tempered by confidence in the information and recommendations issued by the government concerning AI and, in the long term, by a high perceived self-efficiency to deal with AI. Indeed, not only has poultry consumption been affected in terms of the quantity consumed, but alternative ways of selecting and preparing poultry have also been adopted as anti-risk practices. Risk communication strategies should take this into account, and rely on a previous assessment of consumer practices adopted to deal with the risk. 相似文献
312.
Emanuele Borgonovo 《Risk analysis》2008,28(3):667-680
In this work, we introduce a generalized rationale for local sensitivity analysis (SA) methods that allows to solve the problems connected with input constraints. Several models in use in the risk analysis field are characterized by the presence of deterministic relationships among the input parameters. However, SA issues related to the presence of constraints have been mainly dealt with in a heuristic fashion. We start with a systematic analysis of the effects of constraints. The findings can be summarized in the following three effects. (i) Constraints make it impossible to vary one parameter while keeping all others fixed. (ii) The model output becomes insensitive to a parameter if a constraint is solved for that parameter. (iii) Sensitivity analysis results depend on which parameter is selected as dependent. The explanation of these effects is found by proposing a result that leads to a natural extension of the local SA rationale introduced in Helton (1993) . We then extend the definitions of the Birnbaum, criticality, and the differential importance measures to the constrained case. In addition, a procedure is introduced that allows to obtain constrained sensitivity results at the same cost as in the absence of constraints. The application to a nonbinary event tree concludes the article, providing a numerical illustration of the above findings. 相似文献
313.
Aviation insurance premiums have become a heavy burden for the airline industry since September 11, 2001. Although the industry must constantly balance its operations between profitability and safety, the reality is that airlines are in the business of making money. Therefore, their ability to reduce cost and manage risk is a key factor for success. Unlike past research, which used subjective judgment methods, this study applied quantitative historical data (1999–2000) and gray relation analysis to identify the primary factors influencing ratemaking for aviation insurance premiums. An empirical study of six airlines in Taiwan was conducted to determine these factors and to analyze the management strategies used to deal with them. Results showed that the loss experience and performance of individual airlines were the key elements associated with aviation insurance premiums paid by each airline. By identifying and understanding the primary factors influencing ratemaking for aviation insurance, airlines will better understand their relative operational strengths and weaknesses, and further help top management identify areas for further improvement. Knowledge of these factors combined with effective risk management strategies, may result in lower premiums and operating costs for airline companies. 相似文献
314.
Seismic risk can be reduced by implementing newly developed seismic provisions in design codes. Furthermore, financial protection or enhanced utility and happiness for stakeholders could be gained through the purchase of earthquake insurance. If this is not so, there would be no market for such insurance. However, perceived benefit associated with insurance is not universally shared by stakeholders partly due to their diverse risk attitudes. This study investigates the implied seismic design preference with insurance options for decisionmakers of bounded rationality whose preferences could be adequately represented by the cumulative prospect theory (CPT). The investigation is focused on assessing the sensitivity of the implied seismic design preference with insurance options to model parameters of the CPT and to fair and unfair insurance arrangements. Numerical results suggest that human cognitive limitation and risk perception can affect the implied seismic design preference by the CPT significantly. The mandatory purchase of fair insurance will lead the implied seismic design preference to the optimum design level that is dictated by the minimum expected lifecycle cost rule. Unfair insurance decreases the expected gain as well as its associated variability, which is preferred by risk-averse decisionmakers. The obtained results of the implied preference for the combination of the seismic design level and insurance option suggest that property owners, financial institutions, and municipalities can take advantage of affordable insurance to establish successful seismic risk management strategies. 相似文献
315.
Kenneth T. Bogen 《Risk analysis》2008,28(4):1033-1051
The U.S. Environmental Protection Agency (USEPA) guidelines for cancer risk assessment recognize that some chemical carcinogens may have a site-specific mode of action (MOA) involving mutation and cell-killing-induced hyperplasia. The guidelines recommend that for such dual MOA (DMOA) carcinogens, judgment should be used to compare and assess results using separate \"linear\" (genotoxic) versus \"nonlinear\" (nongenotoxic) approaches to low-level risk extrapolation. Because the guidelines allow this only when evidence supports reliable risk extrapolation using a validated mechanistic model, they effectively prevent addressing MOA uncertainty when data do not fully validate such a model but otherwise clearly support a DMOA. An adjustment-factor approach is proposed to address this gap, analogous to reference-dose procedures used for classic toxicity endpoints. By this method, even when a \"nonlinear\" toxicokinetic model cannot be fully validated, the effect of DMOA uncertainty on low-dose risk can be addressed. Application of the proposed approach was illustrated for the case of risk extrapolation from bioassay data on rat nasal tumors induced by chronic lifetime exposure to naphthalene. Bioassay data, toxicokinetic data, and pharmacokinetic analyses were determined to indicate that naphthalene is almost certainly a DMOA carcinogen. Plausibility bounds on rat-tumor-type-specific DMOA-related uncertainty were obtained using a mechanistic two-stage cancer risk model adapted to reflect the empirical link between genotoxic and cytotoxic effects of the most potent identified genotoxic naphthalene metabolites, 1,2- and 1,4-naphthoquinone. Bound-specific adjustment factors were then used to reduce naphthalene risk estimated by linear extrapolation (under the default genotoxic MOA assumption), to account for the DMOA exhibited by this compound. 相似文献
316.
This article aims to investigate parental influence on high-risk behavior by young people. Although research on the topic of perception of risk demonstrates that it is socially constructed, the role of the family in this construction has rarely been studied. Using a French national survey of more than 1,200 young drivers between the ages of 18 and 25, and their parents, we attempt to understand the transmission of risk within families. Our econometric study shows that parents influence both the practices and representations of their children. When parental norms and values are transmitted, they are by no means accepted in a wholly passive way. Indeed, the parental model is in competition with other models that originate from both inside the family (brothers and sisters) and outside it (instructors). Furthermore, parental influence decreases over time as young people become more experienced drivers and construct their own identity with regard to risk. 相似文献
317.
Wim Verbeke Filiep Vanhonacker Lynn J. Frewer Isabelle Sioen Stefaan De Henauw John Van Camp 《Risk analysis》2008,28(4):951-967
Communicating about the health effects of fish and seafood may potentially result in a conflict situation: increasing intake is desirable because of health and nutritional benefits, but higher consumption may also lead to an increased intake of potentially harmful environmental contaminants. In order to anticipate the communication challenge this conflict may pose, the research presented here aimed to assess the impact of risk/benefit communication on Belgian consumers' fish consumption behavior and fish attribute perception. Data were collected in June 2005 from a sample of 381 women, aged between 20 and 50 years. An experimental design consisting of four message conditions (benefit‐only; risk‐only; benefit‐risk; and risk‐benefit) combined with three information sources (fish and food industry; consumer organization; government) was used. Exposure to the benefit‐only message resulted in an increase from a self‐reported fish consumption frequency of 4.2 times per month to an intended fish consumption frequency of 5.1 times per month (+21%), while fish attribute perceptions only marginally improved. The risk‐only message resulted in a strong negative perceptual change in the range of two points on a seven‐point scale. This translated into an 8% decrease of behavioral intention (from eating fish 4.5 times per month to an intention of eating fish 4.1 times per month). Balanced messages referring to both risks and benefits yielded no significant change in behavioral intention, despite a significant worsening of fish attribute perception. The presentation order of benefits and risks in the balanced message showed a tendency to affect both behavioral intention and attribute perception, with the first message component being most influential. Information source did not yield any significant impact either on behavioral intention or on attribute perceptions, independent of the message content. The results from this study provide valuable insights for future risk/benefit and balanced communication about seafood. 相似文献
318.
When applying the contingent valuation method (CVM) in risk reduction studies, some studies report that willingness to pay (WTP) is insensitive to the magnitude of risk reduction while other studies do not. On the other hand, social-psychological research has shown that the affect heuristic biases judgments on probability, relative frequency, and risk. This article examines both magnitude (or scope) effect and affect heuristic (or representation) effect on WTP for risk reduction measures against tsunamis by introducing two experimental (i.e., absolute and relative) systems with four different representations to evaluate public behaviors in two different scenarios of risk reduction. Two common denominators (100 and 10,000) are introduced into absolute risk reduction representation (i.e., \"of every 100 persons, from present 2 deaths to 1\") to form different formats (i.e., \"of every 10,000 persons from 200 to 100,\" and \"of every 100,000 persons from 2,000 deaths to 1,000\"). There is little evidence that WTP estimates are sufficiently sensitive to the magnitude of risk reduction, but relative risk reduction representations may be better than the absolute one given in CVM mail surveys when the risk is small. There is a statistically insignificant effect of risk reduction representations on respondent frequency, but mixed effects on the monetary values of WTP at the level of 0.05. The representation effect of absolute risk reduction on the WTP value varies with the common denominator. The larger the common denominator, the less the WTP to reduce the risk of tsunamis, and the significance probability is improved to less than the level of 0.05 when the common denominator becomes large enough. The findings suggest that improved methods are required for estimating the rates of tradeoff between fatality risk and other goods among consumers. 相似文献
319.
Fermín Mallor Carmen García-Olaverri Sagrario Gómez-Elvira Pedro Mateo-Collazas 《Risk analysis》2008,28(4):1003-1019
In this article, we present a methodology to assess the risk incurred by a participant in an activity involving danger of injury. The lack of high-quality historical data for the case considered prevented us from constructing a sufficiently detailed statistical model. It was therefore decided to generate a risk assessment model based on expert judgment. The methodology is illustrated in a real case context: the assessment of risk to participants in a San Fermin bull-run in Pamplona (Spain). The members of the panel of \"experts on the bull-run\" represented very different perspectives on the phenomenon: runners, surgeons and other health care personnel, journalists, civil defense workers, security staff, organizers, herdsmen, authors of books on the bull-run, etc. We consulted 55 experts. Our methodology includes the design of a survey instrument to elicit the experts' views and the statistical and mathematical procedures used to aggregate their subjective opinions. 相似文献
320.
Emergency response is directly related to the allocation of emergency rescue resources. Efficient emergency response can reduce loss of life and property, limit damage from the primary impact, and minimize damage from derivative impacts. An appropriate risk analysis approach in the event of accidents is one rational way to assist emergency response. In this article, a cellular automata‐based systematic approach for conducting risk analysis in emergency response is presented. Three general rules, i.e., diffusive effect, transporting effect, and dissipative effect, are developed to implement cellular automata transition function. The approach takes multiple social factors such as population density and population sensitivity into consideration and it also considers risk of domino accidents that are increasing due to increasing congestion in industrial complexes of a city and increasing density of human population. In addition, two risk indices, i.e., individual risk and aggregated weighted risk, are proposed to assist decision making for emergency managers during emergency response. Individual risk can be useful to plan evacuation strategies, while aggregated weighted risk can help emergency managers to allocate rescue resources rationally according to the degree of danger in each vulnerable area and optimize emergency response programs. 相似文献