Ian H. Langford

A quantitative test of the cultural theory of risk perceptions: Comparison with the psychometric paradigm

This paper seeks to compare two frameworks which have been proposed to explain risk perceptions, namely, cultural theory and the psychometric paradigm. A structured questionnaire which incorporated elements from both approaches was administered to 129 residents of Norwich, England. The qualitative risk characteristics generated by the psychometric paradigm explained a far greater proportion of the variance in risk perceptions than cultural biases, though it should be borne in mind that the qualitative characteristics refer directly to risks whereas cultural biases are much more distant variables. Correlations between cultural biases and risk perceptions were very low, but the key point was that each cultural bias was associated with concern about distinct types of risks and that the pattern of responses was compatible with that predicted by cultural theory. The cultural approach also provided indicators for underlying beliefs regarding trust and the environment; beliefs which were consistent within each world view but divergent between them. An important drawback, however, was that the psychometric questionnaire could only allocate 32% of the respondents unequivocally to one of the four cultural types. The rest of the sample expressed several cultural biases simultaneously, or none at all. Cultural biases are therefore probably best interpreted as four extreme world views, and a mixture of qualitative and quantitative research methodologies would generate better insights into who might defend these views in what circumstances, whether there are only four mutually exclusive world views or not, and how these views are related to patterns of social solidarity, and judgments on institutional trust.

Elicitation and truncation effects in contingent valuation studies

Abstract The contingent valuation method (CVM) uses surveys of expressed preferences to evaluate willingness to pay for (generally) non-market, environmental goods. This approach gives the method theoretical applicability to an extensive range of use and passive-use values associated with such goods. However, recent years have seen the method come under sustained empirical and theoretical attack by critics who claim that the expressed preference statements given by respondents to CVM questions are subject to a variety of biases to the extent that “true” valuations cannot be inferred. This debate was reviewed and assessed in the recent report of the US, NOAA “blue-ribbon” panel which gave cautious approval to the method subject to adherence to a rigorous testing protocol. This paper reports findings from the first UK CVM study to generally conform to those guidelines. The major objective of the research reported on here is the analysis of the effects of altering the method of eliciting willingness to pay (WTP) responses. Three WTP elicitation methods are employed: open-ended questions (where the respondent is free to give any answer); dichotomous choice questions (requiring a yes/no response regarding a set WTP bid level); and iterative bidding questions (where a respondent is free to move up or down from a given WTP starting point). Results indicate that respondents experience significant uncertainty in answering open-ended questions and may exhibit free-riding or strategic overbidding tendencies (although this is less certain). When answering dichotomous choice questions respondents seem to experience much less uncertainty although the suggestion that bid levels affect responses cannot be ruled out, and it is clear that respondents behave somewhat differently to dichotomous choice as opposed to open-ended formats. The iterative bidding approach appears to provide a halfway house with respondents exhibiting certain of the characteristics of both the other formats. We concluded that the level of uncertainty induced by open-ended formats is a major concern, and that further research into the microeconomic motivations of individuals responding to iterative bidding and dichotomous choice CV surveys is high priority. A further aim of the analysis was to test for changes in estimated mean WTP induced by the application of different forms of truncation across all elicitation methods. Recommendations are made on appropriate truncation strategies for each elicitation method.

Non-users' Willingness to Pay for a National Park: An Application and Critique of the Contingent Valuation Method

BATEMAN I. J. and LANGFORD I. H. (1997) Non-users willingness to pay for a National Park: an application and critique of the contingent valuation method, Reg. Studies 31, 571‐582. A great deal of the ongoing academic debate concerning the contingent valuation (CV) method has focused upon whether or not the method is suitable for assessing non-use values. This paper presents results from a study examining non-users values for preserving the Norfolk Broads, a wetland area of recognized international importance, from the threat of saline flooding. Discussion of results centres upon the validity of the CV method for eliciting unbiased estimates of non-use value. A graphical representation of findings from a variety of studies is presented to suggest that such results are logically ordered across goods and valuation scenarios. However, as the paper concludes, logicality and validity are not necessarily synonymous. BATEMAN I. J. et LANGFORD I. H. (1997) La volonte des non-usagers de payer les parcs nationaux:...

Bound and path effects in double and triple bounded dichotomous choice contingent valuation

Dichotomous choice contingent valuation questions are relatively inefficient in that large sample sizes are required for a given level of estimation precision. An increasingly common approach to this problem is to supplement the initial question with subsequent dichotomous choice questions in a multiple-bound design. However, a number of commentators have suggested that such designs may generate responses which are internally inconsistent in that the distribution of underlying preferences implied by answers to the initial question may not be the same as that implied by the entire sequence of replies. We consider a variety of potential causes of such inconsistencies and use data from a contingent valuation study with two follow-ups and post survey debriefing focus groups to test both the effects caused by moving from one bound to another and those caused when respondents follow either the bid-increasing path generated by a positive response at a given bid amount, or the bid-decreasing path generated by negative responses. Results indicate that both bound and path effects are significant and generate a pattern corresponding to certain of the causes of inconsistency identified in the paper. Conclusions for the future application of such designs are presented.

Coastal Management for Sustainable Development: Analysing Environmental and Socio-Economic Changes on the UK Coast

Littoral areas of the British Isles present an array of properties and features which have long been exploited by human populations and have contributed to the wealth and the quality of life of the nation. Past and ongoing differentiation in uses of coastal zones has led to conflicts ranging from deleterious effects on supporting ecosystems to symbiosis with human activities. This paper aims to elicit the main forces influencing the development of coastal areas and the means available to assess the present use and manage future exploitation of the coastal zone, following the P-S-I-R Framework and an ecosystem function-based valuation methodology. A variety of pressures and their trends is analysed (climate change, population and tourism changes, port development, hydrocarbon and marine aggregate extraction and pollution). All these factors are examined in the context of the sustainable use of coastal resources and on the basis of an interdisciplinary ecological economics approach.

Accidents to preschool children : comparing family and neighbourhood risk factors

Accidental injury in young children is more common among poorer families and in deprived areas but little is known about how these factors interact. This paper describes a study to measure the contribution of individual family factors and area characteristics in determining risk of accidental injury among preschool children. We conducted a population based study of preschool accident and emergency attendances over two years in and around the city of Norwich, UK. Information on individual families was extracted from the district child health information system while social areas were constructed from adjacent census enumeration districts with homogeneous social and demographic characteristics. Statistical analysis was by multilevel modelling. Accidental injury rates were much higher in deprived urban neighbourhoods than in affluent areas but the multilevel analysis showed that, for all accidents, much of the variation in rates was accounted for by factors at the individual level i.e. male sex, young maternal age, number of elder siblings and distance from hospital, with a smaller, but independent, influence of living in a deprived neighbourhood. The model for more severe injuries was similar except single parenthood was now significant at the level of individuals and the effect of area deprivation was stronger. We conclude that preschool accidental injuries are influenced by factors operating at both the level of individual families and between areas. This evidence suggests that both social policy changes to improve child care among unsupported young families and targeting accident prevention measures at a local level towards deprived neighbourhoods would reduce accidents.

Multilevel Modelling of the Geographical Distributions of Diseases

Multilevel modelling is used on problems arising from the analysis of spatially distributed health data. We use three applications to demonstrate the use of multilevel modelling in this area. The first concerns small area all-cause mortality rates from Glasgow where spatial autocorrelation between residuals is examined. The second analysis is of prostate cancer cases in Scottish counties where we use a range of models to examine whether the incidence is higher in more rural areas. The third develops a multiple-cause model in which deaths from cancer and cardiovascular disease in Glasgow are examined simultaneously in a spatial model. We discuss some of the issues surrounding the use of complex spatial models and the potential for future developments.

Modelling environmental influences on property prices in an urban environment

The aim of this research was to assign money values to the negative impacts associated with road development, more specifically noise and visual intrusion. These impacts do not have observable prices and so have to be calculated indirectly. One way of doing this is to examine their effect upon house prices. The valuations such a method produces can then be included alongside other costs and benefits in the appraisal of a road development. However in order to calculate these prices, one also has to control for the many other factors that affect house prices, in addition to specifying the two road variables. In previous research this has required much time and effort which has consequently limited the scope of such studies. The aim of this project was to use a geographical information system (GIS) and large-scale digital data to derive all the required variables in a quick and efficient manner. The flexibility of a GIS allows a large number of possible explanatory variables to be calculated, leading to a large and complex dataset. This paper describes how such a dataset was modelled and price estimates for road noise and the visual intrusion extracted. It concludes by commenting upon the benefits of using GIS in this type of study and considers the main limitations to their wider adoption.

The potential effects of climate change on winter mortality in England and Wales

In Britain death rates from several important causes, particularly circulatory and respiratory diseases, rise markedly during the colder winter months. This close association between temperature and mortality suggests that climate change as a result of global warming may lead to a future reduction in excess winter deaths. This paper gives a brief introductory review of the literature on the links between cold conditions and health, and statistical models are subsequently developed of the associations between temperature and monthly mortality rates for the years 1968 to 1988 for England and Wales. Other factors, particularly the occurrence of influenza epidemics, are also taken into account. Highly significant negative associations were found between temperature and death rates from all causes and from chronic bronchitis, pneumonia, ischaemic heart disease and cerebrovascular disease. The statistical models developed from this analysis were used to compare death rates for current conditions with those that might be expected to occur in a future warmer climate. The results indicate that the higher temperatures predicted for 2050 might result in nearly 9000 fewer winter deaths each year with the largest contribution being from mortality from ischaemic heart disease. However, these preliminary estimates might change when further research is able to make into account a number of additional factors affecting the relationship between mortality and climate.

Public Attitudes to Contingent Valuation and Public Consultation

The use of cost-benefit analysis (CBA) in environmental decision-making and the contingent valuation (CV) technique as input into traditional CBA to elicit environmental values in monetary terms has stimulated an extensive debate. Critics have questioned the appropriateness of both the method and the technique. Some alternative suggestions for the elicitation of environmental values are based on a social process of deliberation. However, just like traditional economic theory, these alternative approaches may be questioned on their implicit value judgements regarding the legitimacy of the social-political organisation of the process of value elicitation. Instead of making assumptions a priori , research efforts should be focused on the processes by which actual public attitudes and preferences towards the environment can best be elicited and fed into environmental or other public policy decision-making. In the study presented in this paper, support was found for both the individual WTP based approach and a participatory social deliberation approach to inform the environmental decision-making process, suggesting that a combination of both approaches is most appropriate.