The opportunity of switching from road to rail or to a combination of road and rail (intermodal) transport is being considered in many countries with the objective of risk reduction in the transport of dangerous goods. This work presents a quantitative approach based on risk analysis for comparing the hazards of road, rail, and intermodal transport, aimed at defining criteria for selecting the safest transport modality. When comparing road and rail transport, the risk mainly depends on the hazardous characteristics of the product. The size of the containers is generally larger for rail transport than for road transport, and consequently the amount of product potentially released, giving rise to impact areas slightly or significantly larger for rail than for road transport. When comparing road and intermodal transport, route length plays the most significant role: the longer the distance, the safer the intermodal transport.

This study tested between two interpretations of confidence in diagnostic hypotheses: expected probability of being correct and conflict experienced during the diagnostic process. Physicians generated hypotheses for case histories with two plausible diagnoses, one having a higher population base rate but less severe clinical consequences than the other. Case information indicative of the two diagnoses was varied. Generation proportions for the two diagnoses and confidence judgments both deviated from the predictions of a Bayesian belief model, but in different ways. Generation of a hypothesis increased with diagnosis-consistent information and diagnosis base rates, but was not reduced by diagnosis-inconsistent information. Confidence was sensitive to both consistent and inconsistent information, but was not very sensitive to diagnosis base rates. Physician characteristics also affected hypothesis generation and confidence differentially. Female doctors had lower confidence in their diagnoses than male doctors, yet there were no gender differences in hypothesis generation. Experience affected hypothesis generation monotonically via the increased availability of previously diagnosed cases, while confidence first increased and then decreased with doctors' experience. The results are consistent with an interpretation of confidence judgments as an expression of decision conflict rather than an indication of likely diagnosis accuracy.

Bayesian advocates of expected utility maximization use sets of probability distributions to represent very different ideas. Strict Bayesians insist that probability judgment is numerically determinate even though the agent can represent such judgments only in imprecise terms. According to Quasi-Bayesians rational agents may make indeterminate subjective probability judgments. Both kinds of Bayesians require that admissible options maximize expected utility according to some probability distribution. Quasi-Bayesians permit the distribution to vary with the context of choice. Maximalists allow for choices that do not maximize expected utility against any distribution. Maximiners mandate what maximalists allow. This paper defends the quasi-Bayesian view against strict Bayesians, on the one hand, and maximalists and maximiners, on the other.

Decisions based on risk analysis require some form of risk acceptance criteria. Presently the International Maritime Organisation (IMO) has initiated an activity on developing a risk-based approach to safety and environmental protection regulations. Explicit risk estimates are new to the organisation. A limited number of FSA trial apllications have been presented so far. Whilst giving increased general knowledge of the risk level in the industry, the debate about risk acceptance has just started.

The objective of this paper is to outline an approach by which societal risk acceptance criteria may be established. The idea is to discriminate between activities representing different risks and importance to society. The societal risk acceptance criteria are calibrated against occupational fatality rates, and transportation fatality rate for scheduled air traffic worldwide. Examples are given for some different ship types. For the sake of discussion a societal risk acceptance for Near Earth objects colliding with the Earth is also derived. It should be noted that many other criteria would be needed in the decision process, like for example individual risks, criteria based on cost effectiveness, and criteria for environmental consequences. Normally a decision would have to be based on acceptance by all these criteria. Only one specific method to arrive at societal risk criteria is dealt with herein. The examples given for some ship types show that when the importance to the society is accounted for, the established FN acceptance curves vary within 1 to 2 orders of magnitude.

The outlined method may be considered for any type of activity above a certain size. An obvious limitation for the method is represented by activities of high economic value with low labour intensity in remote places, for example exploitation of offshore oil and gas resources.

This paper develops a behavioral model of farmer decision making to analyze the incentives for adoption of a technology that provides information about spatial variability in nutrient availability and enables variable rate application of fertilizers. It examines the implications of uncertainty about the accuracy of the technology on input application and adoption decisions. Risk aversion and uncertainty can lead to the imposition of a risk premium on input use, which create incentives to over or under apply fertilizers. This influences not only the incentives to adopt the technology but also the impact of adoption on pollution. High spatial variability mitigates the disincentives for adoption even if fixed costs are high and farm size is small but the extent to which this occurs depends on the degree of risk aversion and uncertainty. These results have implications for the design and effectiveness of cost–share subsidies to induce adoption and reduce over application of fertilizers.

Physician risk management (RM) has been mandated around the world in an effort to reduce pecuniary and non-pecuniary loss associated with avoidable patient injury. However, there has been little empirical RM assessment to determine whether physicians obtain an increased understanding of the law, clinical obligations defined by law, and reduced numbers of injury suits. Here, 210 US primary care physicians were sent a survey requesting demographic information on RM activities, the definition of negligence, and evaluation of ten patient injury jury verdict case scenarios; 138 physicians responded. Although physicians participated in a broad array of RM activities, none were positively associated with overall concordance with case verdicts; indeed, substantive self-study and RM seminar attendance <24 months ago were associated with worse concordance. Recent RM seminar attendance, clinical practice guideline (CPG) use, and self-study were associated with worse concordance in defendant verdict cases; CPG use was correlated with better concordance in plaintiff verdict cases. Respondent physicians were significantly harsher in case evaluations overall when they used insurer CPGs and for defendant verdict cases when they used insurer CPGs, engaged in substantive self-study, or recently attended RM seminars. No RM method was found to correlate with successful jury verdict prediction; having been sued was negatively correlated with defendant verdict case prediction. Finally, respondent physicians had a higher number of patient injury suits associated with participation in RM malpractice training at the training site, RM seminar training, and RM seminar attendance <24 months ago, or if they acted as an expert/consultant in malpractice cases. Most physicians could not identify the rule of negligence; yet correct identification of the negligence rule was not correlated with concordance, prediction, or number of patient injury suits. Thus, physician RM efforts may not be effective in promoting patient safety, may increase risk of patient injury, and may not reduce pecuniary and non-pecuniary costs associated with patient injury.

When people attempt to evaluate their personal standing on a variety of dimensions, they often compare themselves with others. This assertion was central to the development of social comparison theory (Festinger, 1954), and has stimulated nearly 50 years of research – primarily in the areas of social psychology, clinical psychology, organizational behavior, and sociology. Social comparison processes have been explored in a broad range of domains including coping, negotiation, academic and work performance, happiness, emotion, and motivation. Numerous volumes have appeared on extensions and applications of the theory, including a recent handbook edited by Suls and Wheeler (2000).

This study investigates the relationship between expressed consumption of proteins and attitudes towards GM foods. 600 shoppers in a city centre supermarket were surveyed concerning attitudes towards GM foods and the frequency of consumption of various proteins. In addition, various demographic variables were measured. In terms of demographics, sex was the best predictor of consumption and attitudes, followed by socioeconomic status and age. Attitudes were found to correlate positively with consumption of several proteins. Explanations are offered in terms of the theories of reasoned action, cognitive dissonance and attribution and the health belief model.

Research in USA and the UK has revealed that whilst the incidence of breast cancer is lower in women from black and ethnic minority groups, African and African-American women delay seeking help, have a worse prognosis, and a higher mortality rate. A variety of reasons has been suggested for this: from system delay, to delay by the women arising from educational and socio-economic disadvantage or religious beliefs. Building on this in the UK, from a study conducted in a South London Screening Clinic, a sub-sample of African and African-Caribbean women were interviewed to obtain their narratives of action in delay in seeking help for late-stage breast cancer. The findings suggest that the women were aware of the services offered, were expecting a diagnosis of cancer, but offered a model of fearing extrusion from their community rather than fear of death from the disease, leading to delay in seeking help. The reasons for this are explored and a risk trajectory in biomedicine compared with the African and African-Caribbean women's world is described.

The regulation of risk is high on the political agenda and viewed as an important component of modernizing government. The Environment Agency of England and Wales has responsibilities for regulating and managing a wide range of risks to and from the environment. In some areas of regulation, a structured and explicit treatent of risk is required; in other areas, the approach is more implicit and reliant on professional judgement. This paper presents an overview of the application of risk assessment in the Environment Agency and a summary of recent policy and regulatory drivers. It introduces some emerging issues with respect to current practice in environmental risk assessment.

In a nuclear processing plant, four departments were compared using a 60-item questionnaire measuring safety attitudes and beliefs including the perception of managers' attitudes and behaviour, communication and risk-taking, and attitudes to taking personal responsibility for safety. Results suggest some differences at the conceptual level in addition to departmental differences and large grade differences. It is proposed that there are certainly two and possibly more differing safety cultures within this organization. The implications of this are discussed in terms of policy.

The self-discovery of a suspicious symptom often brings about an emotional turbulence: while recognizing the importance of having the symptom diagnosed promptly, individuals frequently delay diagnosis, seeking to avoid the pain or discomfort associated with the diagnostic process and fearing to hear that they are developing a serious illness. The present paper proposes a rational, economic-oriented approach to explaining individuals' delay behavior, weighing the fear of the diagnostic procedure and of being told the suspected truth against the fear of consequence of further procrastination. Assuming that the money costs of diagnosis and medical treatment are borne by health insurance, a multi-period expected-utility maximization model is constructed to inquire into the individual's decision of whether and to what extent to delay diagnosis. The results rationalize a variety of observed behavior concerning individuals' reaction to suspicious symptoms that differ in their psychic cost of diagnosis, the likelihood of indicating severe illness and the potential damage to health incurred by delayed diagnosis. The desirability of delayed diagnosis to the health insurer and the socially desired solution are finally discussed.

The paper addresses basic issues associated with incorporating human and organizational factors in risk analysis of hazardous systems. A conceptual framework has been developed for systematic incorporating these factors in probabilistic models and the risk assessment to be used for the safety management. The methodology outlined in the paper is a synthesis or generalization of techniques and procedures used for performing HRA in the context of PSA, applying both the quantitative and qualitative methods. The similarities and differences of hierarchical influence diagrams (HIDs) compared with hierarchical structures of the AHP method and the influence diagrams used in the FSA methodology developed by IMO are examined. Illustrative examples are included. Finally a fuzzy extension of the proposed approach is introduced.

It is not uncommon for the invading economist to arrive at radically different conclusions in areas of social inquiry, hitherto left to specialists from other fields. For example, before the arrival of Chicagoan economics, the received wisdom in the criminological field was that deterrent punishments (especially capital punishment) did not work. In this paper, we attend to the simple question: ‘Is religion a beneficial influence on the health of individuals?’ This has not hitherto attracted much attention from economists. However, epidemiological studies have overwhelmingly concluded that the answer to the above question is ‘yes'. In the context of a simple two equation recursive set up, this paper provides sharply contrasting evidence of there being no relationship between the two variables except where an arbitrary five point measure of subjective health status is used. Although the relationship in this case is negative in accordance with the received wisdom, its magnitude is so small that it may be dismissed as inconsequential for reasons discussed in the main body of the paper. This paper deals solely with physical health unlike some of the prior research which also investigates mental health status.

Genetic algorithm search techniques provide an innovative and robust means of optimization in complex, multivariate real-scale problems. In this paper we present an application of genetic algorithms to the optimization of airport operation and development for an increasing traffic situation. The approach is proven successful and much less time consuming compared to traditional what-if analysis. In addition to the base case optimization results, sensitivity analyses both with respect to the economic parameters of the fitness function, subject to the optimization, and with respect to some important genetic algorithm settings have been performed and yield consistent results.

Standards and guidelines often recommend that the warning signal words ‘Danger’, ‘Warning’ and ‘Caution’ are used to denote decreasing levels of hazard on warning signs and labels. However the research into the perceived hazard of these words does not unequivocally support their use in this way. Here we extend the previous research by using a survey methodology and single estimation technique to investigate hazard perceptions of signal words in the UK population. In general our findings support the use of signal words to communicate hazard but we suggest that more research is needed into the specific terms recommended.

This paper describes the HARIA-2 methodology for external emergency planning and analysis. The main aim of the HARIA-2 research project is to investigate the possibility of taking into account not only the physical phenomena, but also sociological aspects in technological emergencies. The methodology has been implemented in two software packages.

1. DEMONSTRATOR, which allows to efficiently simulate various accident scenarios; it can also be used for training rescue services and as a support tool for decision making during real emergencies;

2. PROTOTYPE system, addressing emergency planning issues, developed on a commercial GIS platform (Arc-View 3.2©); it integrates all data bases and models developed, including those simulating population behaviour and the evacuation plan, even though in a simplified mode.

The paper describes the main aspects of the HARIA-2 methodology and two examples of application, namely the Mexico City disaster (1984) and a simulation exercise of evacuation for the Milazzo industrial area.