Development of a Preliminary Framework for Informing the Risk Analysis and Risk Management of Nanoparticles

Decisions are often made even when there is uncertainty about the possible outcomes. However, methods for making decisions with uncertainty in the problem framework are scarce. Presently, safety assessment for a product containing engineered nano-scale particles is a very poorly structured problem. Many fields of study may inform the safety assessment of such particles (e.g., ultrafines, aerosols, debris from medical devices), but engineered nano-scale particles may present such unique properties that extrapolating from other types of studies may introduce, and not resolve, uncertainty. Some screening-level health effects studies conducted specifically on engineered nano-scale materials have been published and many more are underway. However, it is clear that the extent of research needed to fully and confidently understand the potential for health or environmental risk from engineered nano-scale particles may take years or even decades to complete. In spite of the great uncertainty, there is existing research and experience among researchers that can help to provide a taxonomy of particle properties, perhaps indicating a relative likelihood of risk, in order to prioritize nanoparticle risk research. To help structure this problem, a framework was developed from expert interviews of nanotechnology researchers. The analysis organizes the information as a system based on the risk assessment framework, in order to support the decision about safety. In the long term, this framework is designed to incorporate research results as they are generated, and therefore serve as a tool for estimating the potential for human health and environmental risk.     

Expert Judgment in Risk Analysis and Management: Process, Context, and Pitfalls

The regulation and management of hazardous industrial activities increasingly rely on formal expert judgment processes to provide wisdom in areas of science and technology where traditional "good science" is, in practice, unable to supply unambiguous "facts." Expert judgment has always played a significant, if often unrecognized, role in analysis; however, recent trends are to make it formal, explicit, and documented so it can be identified and reviewed by others. We propose four categories of expert judgment and present three case studies which illustrate some of the pitfalls commonly encountered in its use. We conclude that there will be an expanding policy role for formal expert judgment and that the openness, transparency, and documentation that it requires have implications for enhanced public involvement in scientific and technical affairs.     

Elicitation of Subjective Probabilities when the Initial Endowment is Unobservable

In the framework of subjective expected utility theory we develop two distinct procedures for the elicitation of a person's subjective probabilities when the initial endowment is random and unobservable. Procedures of the first kind rely on the boundedness of the utility function to elicit the person's subjective probabilities directly. Procedures of the second kind infer the person's initial endowment from his choice behavior prior to the application of probability elicitation.     

谈体育课中的"激发教学"

本文论述了在体育课中应用"激发教学"的意义和途径.通过对"教材激发"和"教法激发"的阐释,努力探索出一条体育中"激发教学"的新路子,使体育课堂教学寓教于兴趣之中,增强体质,强化了教学效果,又陶冶了学生的情操.     

Combining Experts’ Judgments: Comparison of Algorithmic Methods Using Synthetic Data

Expert judgment (or expert elicitation) is a formal process for eliciting judgments from subject‐matter experts about the value of a decision‐relevant quantity. Judgments in the form of subjective probability distributions are obtained from several experts, raising the question how best to combine information from multiple experts. A number of algorithmic approaches have been proposed, of which the most commonly employed is the equal‐weight combination (the average of the experts’ distributions). We evaluate the properties of five combination methods (equal‐weight, best‐expert, performance, frequentist, and copula) using simulated expert‐judgment data for which we know the process generating the experts’ distributions. We examine cases in which two well‐calibrated experts are of equal or unequal quality and their judgments are independent, positively or negatively dependent. In this setting, the copula, frequentist, and best‐expert approaches perform better and the equal‐weight combination method performs worse than the alternative approaches.     

Reducing Overconfidence in the Interval Judgments of Experts

Elicitation of expert opinion is important for risk analysis when only limited data are available. Expert opinion is often elicited in the form of subjective confidence intervals; however, these are prone to substantial overconfidence. We investigated the influence of elicitation question format, in particular the number of steps in the elicitation procedure. In a 3‐point elicitation procedure, an expert is asked for a lower limit, upper limit, and best guess, the two limits creating an interval of some assigned confidence level (e.g., 80%). In our 4‐step interval elicitation procedure, experts were also asked for a realistic lower limit, upper limit, and best guess, but no confidence level was assigned; the fourth step was to rate their anticipated confidence in the interval produced. In our three studies, experts made interval predictions of rates of infectious diseases (Study 1, n = 21 and Study 2, n = 24: epidemiologists and public health experts), or marine invertebrate populations (Study 3, n = 34: ecologists and biologists). We combined the results from our studies using meta‐analysis, which found average overconfidence of 11.9%, 95% CI [3.5, 20.3] (a hit rate of 68.1% for 80% intervals)—a substantial decrease in overconfidence compared with previous studies. Studies 2 and 3 suggest that the 4‐step procedure is more likely to reduce overconfidence than the 3‐point procedure (Cohen's d = 0.61, [0.04, 1.18]).     

建设项目绿色创新努力及利他偏好诱导

建设项目绿色创新有赖于相关参与方的协同努力,利他偏好对合作参与方的自身努力与合作努力行为决策存在影响,通过建立项目绿色创新中主导方与成员方间的Stackelberg博弈模型,分析"分散—分散"与"集中—集中"两种决策结构情境下考虑利他偏好影响的绿色创新努力行为决策,得到以下结论：（1）在大多数情形下,利他偏好会对建设项目参与方努力行为产生正面作用,但具体影响程度与影响方向受所处的决策结构情境以及参与方间的利他偏好差异影响;（2）收益分配等因素影响参与方的两类努力行为决策,但是参与方间的利他偏好差异变化会改变收益分配对努力行为的影响方向,即利他偏好通过收益分配间接影响参与方努力决策;（3）收益的公平分配、适度的努力成本以及社会声誉激励可对利他行为形成诱导。由此,在利他偏好之于努力行为决策影响的研究中考虑情境及相关因素的影响,将使得结论更贴近现实。     

The Value of Performance Weights and Discussion in Aggregated Expert Judgments

In risky situations characterized by imminent decisions, scarce resources, and insufficient data, policymakers rely on experts to estimate model parameters and their associated uncertainties. Different elicitation and aggregation methods can vary substantially in their efficacy and robustness. While it is generally agreed that biases in expert judgments can be mitigated using structured elicitations involving groups rather than individuals, there is still some disagreement about how to best elicit and aggregate judgments. This mostly concerns the merits of using performance‐based weighting schemes to combine judgments of different individuals (rather than assigning equal weights to individual experts), and the way that interaction between experts should be handled. This article aims to contribute to, and complement, the ongoing discussion on these topics.     

‘The shops were only made for people who could walk’: impairment,barriers and autonomy in the mobility of adults with Cerebral Palsy in urban England

ABSTRACT

Based on research carried out with a group of adults with Cerebral Palsy in Birmingham, UK, we consider the complex inter-relationship between the accessibility of the urban environment for those with impaired gross motor skills, and the ability of these people to lead full and independent lives. Drawing on a framework that considers mobility as movement, meaning-making and political, we demonstrate the reality of differentiated mobility. For those with bodies that function outside the presumed operating parameters of the model subjects of urban design, mobility may be possible, but is often uncomfortable and even dangerous, with significant associated effects for impaired people’s autonomy. Our study details social and structural, or design, barriers to people’s mobility, demonstrating the inter-connection between individuals’ behaviour and urban design in a manner that questions a clear distinction between the two. We draw upon the notions of emotional work and a commoning approach to mobility in suggesting that further investment in urban accessibility is squarely an issue of social justice.     

精简教材内容 注重教学方法 提高教学质量--浅析《道路勘测设计》课程教学改革

针对目前《道路勘测设计》课程内容多学时少这一主要矛盾,提出了以精简教材内容、注重教学方法、提高教学质量为主的课程教学改革方案。特别强调了应加强启发式教学和学生自学,以求锻炼学生的创造性思维,逐步培养学生独立思考问题和分析问题的能力,亦即注重对学生智能和素质的培养。