Who Reaps the Benefits,Who Bears the Risks? Comparative Optimism,Comparative Utility,and Regulatory Preferences for Mobile Phone Technology

Although the issue of risk target (e.g., self, others, children) is widely acknowledged in risk perception research, its importance appears underappreciated. To date, most research has been satisfied with demonstrating comparative optimism, i.e., lower perceived risk for the self than others, and exploring its moderators, such as perceived controllability and personal exposure. Much less research has investigated how the issue of target may affect benefit perceptions or key outcomes such as stated preferences for hazard regulation. The current research investigated these issues using data from a public survey of attitudes toward mobile phone technology (N= 1,320). First, results demonstrated comparative optimism for this hazard, and also found moderating effects of both controllability and personal exposure. Second, there was evidence of comparative utility, i.e., users believed that the benefits from mobile phone technology are greater for the self than others. Third, and most important for policy, preferences for handset regulation were best predicted by perceptions of the risks to others but perceived benefits for the self. Results suggest a closer awareness of target can improve prediction of stated preferences for hazard regulation and that it would be profitable for future research to pay more attention to the issue of target for both risk and benefit perceptions.     

Morality and Nuclear Energy: Perceptions of Risks and Benefits,Personal Norms,and Willingness to Take Action Related to Nuclear Energy

We examined factors underlying people's willingness to take action in favor of or against nuclear energy from a moral perspective. We conducted a questionnaire study among a sample of the Dutch population (N = 123). As expected, perceptions of risks and benefits were related to personal norms (PN), that is, feelings of moral obligation toward taking action in favor of or against nuclear energy. In turn, PN predicted willingness to take action. Furthermore, PN mediated the relationships between perceptions of risk and benefits and willingness to take action. In line with our hypothesis, beliefs about the risks and benefits of nuclear energy were less powerful in explaining PN for supporters compared to PN of opponents. Also, beliefs on risks and benefits and PN explained significantly more variance in willingness to take action of opponents than of supporters. Our results suggest that a moral framework is useful to explain willingness to take action in favor of and against nuclear energy, and that people are more likely to protest in favor of or against nuclear energy when PN are strong.     

Synthetic-Fuel Plants: Potential Tumor Risks to Public Health

This article quantifies potential public health risks from tumor-producing pollutants emitted from two synthetic-fuel plants (direct liquefaction--Exxon Donor Solvent: and indirect liquefaction--Lurgi Fischer-Tropsch) located at a representative site in the eastern United States. In these analyses gaseous and aqueous waste streams were characterized; exposures via inhalation, terrestrial and aquatic food chains, and drinking water supplies were modeled. Analysis suggested that emissions of "polycyclic aromatic hydrocarbons," "aromatic amines," "neutral N, O, S heterocyclics," "nitriles," and "other trace elements" pose the largest quantifiable risks to public health. Data and analysis for these pollutant categories should be refined to more accurately match compound-specific estimated exposure levels with tumorigenic potency estimates. Before these results are used for regulatory purposes, more detailed analysis for selected pollutant classes are needed, and more sophisticated aquatic exposure models must be developed. Also, differences in geographic scales among the environmental transport models used need to be rectified.     

Public Perceptions of the Risks and Benefits of Technology1

This study attempted to verify and extend previous research on people's perceptions of the risks and benefits of technology and their judgments concerning the acceptability of technology safety regulations. The study addressed several limitations of prior work, in that: (1) it was the first “expressed-preference” study to collect data from large, representative samples of Americans; (2) the research design made “person,” rather than “technology,” the unit of statistical analysis; and (3) the study employed an expanded set of independent variables, including three qualitative benefit characteristics. The results confirmed several major conclusions of prior expressed-preference research, the most important being that members of the public tend to define “risks,”“benefits,” and “acceptability” in a complex, multidimensional manner; and that their definitions differ significantly from those used by professional risk-managers and other technical experts in quantitative assessments of risk and acceptability. The results also indicated that people's stances toward technology regulation tend to cut across traditional sociodemographic lines.     

Methylmercury Risks and EPA + DHA Benefits Associated with Seafood Consumption in Europe

The intake of methyl‐Hg and EPA + DHA through consumption of seafood in Europe as well as the associated probability of exceeding the provisional tolerable weekly intake (PTWI) and the recommended daily intake (RDI), respectively, were estimated by combining methyl‐Hg and EPA + DHA contents in the five most consumed seafood species with hypothesized consumption distributions for eight European countries, chosen on the basis of size and representative significance. Two estimators were used: plug‐in (PI) and tail estimation (TE). The latter was based on the application of the extreme value theory to the intakes distribution curves. Whereas contents data were collected from own database and published scientific papers, consumption data were obtained from statistical sources of the various countries. Seafood consumption levels varied considerably between countries, from 140 in the United Kingdom to 628.5 g/(person.week) in Iceland. The main consumed species were also different between countries. The probability of exceeding the methyl‐Hg PTWI ranged from 0.04% in the United Kingdom to 9.61% in Iceland. Concerning the probability of exceeding the RDI of EPA + DHA, Iceland was third, after Portugal (66.05%) and Spain (61.05%) and the United Kingdom was the last (0.32%). While TE was most accurate for small probabilities, PI yielded best estimates for larger probabilities.     

Characterising the Perceived Risks and Benefits of Some Health Issues

Previous work on perceived risk, particularly a study by Fischhoff et al. (1978), is critically examined with reference to its applicability to specific health related issues. Judgments were obtained from 159 subjects of 15 health-related items in terms of perceived risk, benefit, and a number of risk characteristics based on the Fischhoff et al. research. In addition, demographic details concerning sex of respondent, seat belt usage, smoking status, and birth order were collected. Using regression analyses it was found that the direction of the risk-benefit relationship was dependent on the issue being judged. Risk was found to be better explained by ratings of likelihood of mishap and likelihood of death as a consequence of mishap. Benefit was poorly explained by the risk characteristics and demographic data. However, subject group characteristics were shown to be important influences on risk and benefit perception in certain situations. The implications of these results for understanding behavioral decisions involving risk in relation to specific activities are discussed.     

Data Available for Evaluating the Risks and Benefits of MTBE and Ethanol as Alternative Fuel Oxygenates

The wide-scale use of methyl tertiary butyl ether (MTBE) in gasoline has resulted in substantial public controversy and action to ban or control its use due to perceived impacts on water quality. Because oxygenates are still required under federal law, considerable research has focused on ethanol as a substitute for MTBE. In this article, we summarize the currently available literature on the air and water quality risks and benefits of MTBE versus ethanol as alternative fuel oxygenates. We find that MTBE-fuel blends are likely to have substantial air quality benefits; ethanol-fuel blends appear to offer similar benefits, but these may be at least partially negated because of ethanol's propensity to increase emissions and ambient concentrations of some air contaminants. Releases of gasoline containing either MTBE or ethanol could have an impact on some drinking water sources, although the impacts associated with MTBE tend to relate to aesthetics (i.e., taste and odor), whereas the impacts associated with ethanol generally relate to health risk (i.e., greater exposure to gasoline constituents such as benzene). It is likely that these water quality impacts will be outweighed by the air quality benefits associated with MTBE and perhaps ethanol use, which affect a much larger population. A lack of data on environmental exposures and associated health impacts hinders the completion of a comprehensive quantitative risk-benefit analysis, and the available air and water quality data should be evaluated in a broader risk-management context, which considers the potential life-cycle impacts, costs, and feasibility associated with alternative fuel oxygenates.     

Treating and Drinking Well Water in the Presence of Health Risks from Arsenic Contamination: Results from a U.S. Hot Spot

The Safe Drinking Water Act of 1974 regulates water quality in public drinking water supply systems but does not pertain to private domestic wells, often found in rural areas throughout the country. The recent decision to tighten the drinking water standard for arsenic from 50 parts per billion (ppb) to 10 ppb may therefore affect some households in rural communities, but may not directly reduce health risks for those on private wells. The article reports results from a survey conducted in a U.S. arsenic hot spot, the rural area of Churchill County, Nevada. This area has elevated levels of arsenic in groundwater. We find that a significant proportion of households on private wells are consuming drinking water with arsenic levels that pose a health risk. The decision to treat tap water for those on private wells in this area is modeled, and the predicted probability of treatment is used to help explain drinking water consumption. This probability represents behaviors relating to the household's perception of risk.     

Life Cycle Risks for Human Health: A Comparison of Petroleum Versus Bio-Based Production of Five Bulk Organic Chemicals

This article describes the development and application of a generic approach to the comparative assessment of risks related to the production of organic chemicals by petrochemical processes versus white biotechnology. White biotechnology, also referred to as industrial biotechnology, typically uses bio-based feedstocks instead of the fossil raw materials used in the petrochemical sector. The purpose of this study was to investigate whether the production of chemicals by means of white biotechnology has lower conventional risks than their production by petrochemical processes. Conventional risks are the risks of well-established processes, and not those related to genetically modified microorganisms and plants. Our approach combines classical risk assessment methods (largely based on toxicology), as developed by the life cycle assessment (LCA) community, with statistics on technological disasters, accidents, and work-related illnesses. Moreover, it covers the total process chain for both petrochemical and bio-based products from cradle to grave. The approach was applied to five products: the plastics polytrimethylene terephthalate (PTT), polyhydroxyalkanoates (PHA), polyethylene terephthalate (PET), polyethylene (PE), and ethanol. Our results show that the conventional risks related to the white biotechnology products studied are lower than those of the petrochemical products. However, considering the uncertainties with respect to the ranges of input data, the (incomplete) coverage of emissions by the environmental priority strategies (EPS) 2000 method, and the uncertainties of the assumptions made in this study (i.e., large to very large), the differences in results between bio-based and petrochemical products fall into the uncertainty range. Because of this, future research is necessary to decrease the uncertainties before we can conclude that the conventional risks of biotechnologically produced chemicals are lower than those of fossil-fuel-derived chemicals.     

业务外包风险分析与控制

结合现代企业理论中的交易费用理论和“委托-代理”理论,对业务外包风险进行了深入的剖析,详细分析了外包决策和执行两个阶段的风险,并提出了相应的风险控制策略。     

创业团队异质性与新企业绩效:领导者乐观心理的调节作用

异质性是创业团队的重要属性,也是创业研究的热点。本文研究将异质性分为两类:任务相关异质性和身份相关异质性,并分别讨论了两类异质性对新企业绩效的不同影响以及团队领导者乐观心理的调节作用。实证研究发现,在任务相关异质性中,行业经验异质性正向影响新企业绩效,而在身份相关异质性中,年龄相关异质性负向影响新企业绩效;同时,团队领导者的乐观心理正向调节行业和职能经验异质性与新企业绩效之间的关系。     

Different Roles and Viewpoints of Scientific Experts in Advising on Environmental Health Risks

Environmental health risks are often complex, largescale, and uncertain. The uncertainties inherent in these problems permit differences among experts in the appraisal of risks. This raises the question of whether different expert roles exist and, if so, how this affects the policy advice that is given. Here, we present a pilot study of the different roles and viewpoints that can be discerned among scientific experts in the Netherlands. Q methodology was used to empirically explore existing theoretical treatises on different expert roles. In total, 26 electromag­netic field (EMF) experts and 21 particulate matter (PM) experts participated. The responses were analyzed separately for EMF and PM respondents using Q factor analysis. In both the EMF and PM domain, three different expert roles were identified. This suggests that particular expert roles depend on the specific environmental health risk. The results indicate that different expert roles exist among scientists who provide policy advice on environmental health risks. This empirical study adds new data and insights to the literature on expert roles. The results of this study are relevant for the selection and composition of expert committees and the interpretation of expert advice.     

Bounds in Competing Risks Models and the War on Cancer

In 1971, President Nixon declared war on cancer. Thirty years later, many declared this war a failure: the age‐adjusted mortality rate from cancer in 2000 was essentially the same as in the early 1970s. Meanwhile the age‐adjusted mortality rate from cardiovascular disease fell dramatically. Since the causes that underlie cancer and cardiovascular disease are likely dependent, the decline in mortality rates from cardiovascular disease may partially explain the lack of progress in cancer mortality. Because competing risks models (used to model mortality from multiple causes) are fundamentally unidentified, it is difficult to estimate cancer trends. We derive bounds for aspects of the underlying distributions without assuming that the underlying risks are independent. We then estimate changes in cancer and cardiovascular mortality since 1970. The bounds for the change in duration until death for either cause are fairly tight and suggest much larger improvements in cancer than previously estimated.     

实验市场中的股权结构、信息与控制权收益

实验室环境下的决策过程研究可以较好地考察决策变量的行为基础和动态临界值.本文以中国股市中的股权结构为背景,在实验框架下考察了股权结构、信息披露和控制权收益的关系.文章先从理论上计算股东的夏普利值并以此代表股东控制权.再分不同设置变量来实验地考察控制权收益.结果表明:(1)股东控制权越平均,控制权收益越少;大股东与小股东形成"核"联盟的机会越多,其取得控制权的机会越少.(2)信息对控制权收益的影响主要体现在信息在联盟的形成和维持中的作用.(3)大股东夏普利值的高低和信息情况决定了联盟的方式.(4)控制权溢价并不一定就是控制权收益,也许只是大股东为防止自身利益被侵害而支付的成本.(5)信息不完全不一定是坏事,部分信息的隐含更能增加公司的分配效率.     

Helping Individuals to Understand Synergistic Risks: An Assessment of Message Contents Depicting Mechanistic and Probabilistic Concepts

Accumulating evidence shows that certain hazard combinations interact to present synergistic risks. However, little is known about the most effective ways of helping individuals to understand this complex risk concept. More specifically, there is an absence of empirical research that has assessed the relative efficacy of messages that explain either the causal mechanism and/or the probabilistic components of synergistic risks. In an experiment designed to address this issue, we presented participants with messages concerning the synergistic risk of developing esophageal cancer for individuals who consume both tobacco and alcohol. Relative to a control group, we compared the extent to which messages featuring content detailing the underlying biological mechanism, the probabilistic risk, or both improved understanding of the synergistic risk. Our results showed that messages containing details of both the mechanism and probabilistic information were most effective at enabling individuals to understand that the alcohol‐tobacco combination presents a synergistic risk. In addition, large improvements in the accuracy of cancer frequency estimates were observed amongst individuals who received probabilistic information, and the highest relative increase in professed willingness to adopt precautionary behaviors was observed amongst individuals who received the mechanism information only. Importantly, these findings could be utilized in the development of a general model for the communication of synergistic risks. Furthermore, in contrast to previous findings, our study demonstrates that risk messages can be both effective and efficient in helping individuals to acquire a greater understanding of synergistic risks. Acquiring such knowledge could lead to significant improvements in risk‐related decisions concerning combined hazards.     

Assessing Potential Human Health Hazards and Benefits from Subtherapeutic Antibiotics in the United States: Tetracyclines as a Case Study

Many scientists, activists, regulators, and politicians have expressed urgent concern that using antibiotics in food animals selects for resistant strains of bacteria that harm human health and bring nearer a “postantibiotic era” of multidrug resistant “super‐bugs.” Proposed political solutions, such as the Preservation of Antibiotics for Medical Treatment Act (PAMTA), would ban entire classes of subtherapeutic antibiotics (STAs) now used for disease prevention and growth promotion in food animals. The proposed bans are not driven by formal quantitative risk assessment (QRA), but by a perceived need for immediate action to prevent potential catastrophe. Similar fears led to STA phase‐outs in Europe a decade ago. However, QRA and empirical data indicate that continued use of STAs in the United States has not harmed human health, and bans in Europe have not helped human health. The fears motivating PAMTA contrast with QRA estimates of vanishingly small risks. As a case study, examining specific tetracycline uses and resistance patterns suggests that there is no significant human health hazard from continued use of tetracycline in food animals. Simple hypothetical calculations suggest an unobservably small risk (between 0 and 1.75E‐11 excess lifetime risk of a tetracycline‐resistant infection), based on the long history of tetracycline use in the United States without resistance‐related treatment failures. QRAs for other STA uses in food animals also find that human health risks are vanishingly small. Whether such QRA calculations will guide risk management policy for animal antibiotics in the United States remains to be seen.     

Tolerance for Environmental Health Risks: The Influence of Knowledge, Benefits, Voluntariness, and Environmental Attitudes

This study examined factors affecting risk estimates and tolerance among persons directly exposed to environmental health risks. Data were gathered from questionnaires distributed at public hearings regarding proposed air pollution standards for an arsenic emitting copper smelter located in Tacoma, Washington. Approximately 80% of the area residents who attended the hearings completed the questionnaires, and the responses of 347 subjects were analyzed. Results indicated that informal risk estimates and risk tolerance were closely associated with judged benefits of the hazard source, acceptance or denial of vulnerability, judgments of exposure voluntariness, and environmental attitudes. Neither factual knowledge of formal risk estimates and proposed standards nor residential distance from the smelter was found to be closely related to risk tolerance or informal risk estimates. Implications of the results are discussed in relation to past and future studies of reactions to risk, and in relation to risk management policy and practice.     

The Distribution of Risks: Vehicle Occupant Fatalities and Time of the Week

Automobile accident risks vary significantly across populations, places, and times. This study describes the time-varying pattern of societal risk. The relative risks of occupant fatality per person-mile of travel are estimated here for each hour of the week, using 1983 data. The results exhibit a strong time-of-day effect and have a highly skewed frequency distribution, implying wide variations in risk-taking behavior. Indeed, the 168 hourly estimates ranged from a low of 0.32 times the average around Sunday noon to a high of 43 times the average at 3:00 a.m. on Sunday, i.e., by a factor of 134 from bottom to top. Quantile-quantile plots or "Lorenz curves," introduced to display the unequal distribution of risks, show that approximately 34% of the vehicle occupant fatalities occur in hours representing only 5% of the travel. These findings have serious implications for risk analysis. First, when attempting to reconcile objective and subjective risk estimates, risk communicators should carefully control for when and to whom the risk in question is applicable. Second, comparisons of hazards on the basis of average risk are necessarily misleading for risks distributed so unevenly. Third, resource allocation decisions can benefit by knowing how incidence, exposure, and risk vary across time, place, and other relevant variables. Finally, certain cost-benefit analyses that use average values to estimate risk exposure can be misleading.     

Judgments of Chemical Risks: Comparisons Among Senior Managers, Toxicologists, and the Public

Nineteen Senior Managers of a major chemical company in the United Kingdom participated in a survey to determine their attitudes, beliefs, and perceptions regarding risks from chemicals. Similar surveys had previously been conducted with toxicologists and members of the general public in the United States and Canada. In general, the Senior Managers tended to judge risks to be quite small for most chemicals. Moreover, they had lower risk perceptions than did members of the British Toxicological Society and even far lower perceptions of risk than a comparison group of members of the Canadian public. The managers held views that were similar to British toxicologists working in industry and government and dissimilar to the views of toxicologists working in academia. The observed differences between views of managers, toxicologists, and the public must be recognized and understood in order to facilitate communication and constructive efforts to manage chemical risks.     

Adapting to Climate: A Case Study on Riverine Flood Risks in the Netherlands

Climate change may well lead to an increased risk of river floods in the Netherlands. However, the impacts of changes in water management on river floods are larger, either enhancing or reducing flood risks. Therefore, the abilities of water-management authorities to learn that climate and river flows are changing, and to recognize and act upon the implications, are of crucial importance. At the same time, water-management authorities respond to other trends, such as the democratization of decision making, which alter their ability to react to climate change. These complex interactions are illustrated with changes in river flood risk management for the Rhine and the Meuse in the Netherlands over the last 50 years. A scenario study is used to seek insight into the question of whether current water-management institutions and their likely successors are capable of dealing with plausible future flood risks. The scenarios show that new and major infrastructure is needed to keep flood risks at their current level. Such a structural solution to future flood risks is feasible, but requires considerable political will and institutional reform, both for planning and implementation. It is unlikely that reform will be fast enough or the will strong enough.