Using choice experiments to explore the spatial distribution of willingness to pay for rural landscape improvements

We report findings from a choice experiment survey designed to estimate the economic benefits from policy measures which improve the rural landscape under an agri-environment scheme in the Republic of Ireland. Using a panel mixed logit specification to account for unobserved taste heterogeneity we derive individual- specific willingness to pay estimates for each respondent in the sample. We subsequently investigate the existence of spatial dependence of these estimates. Results suggest the existence of positive spatial autocorrelation for all rural landscape attributes. As a means of benefit transfer, kriging methods are employed to interpolate willingness to pay estimates across the whole of the Republic of Ireland. The kriged WTP surfaces confirm the existence of spatial dependence and illustrate the implied spatial variation and regional disparities in WTP for all the rural landscape improvements

Testing the stability of the benefit transfer function for discrete choice contingent valuation data

We examine the stability of the benefit transfer function across 42 recreational forests in the British Isles. A working definition of reliable function transfer is put forward, and a suitable statistical test is provided. The test is based on the sensitivity of the model log-likelihood to removal of individual forest recreation sites. We apply the proposed methodology on discrete choice contingent valuation data and find that a stable function improves our measure of transfer reliability, but not by much. We conclude that, in empirical studies on transferability, function stability considerations are secondary to the availability and quality of site attribute data. Modellers’ can study the advantages of transfer function stability vis-à-vis the value of additional information on recreation site attributes

Reducing Bias from Choice Experiments Estimates in the Demand for Recreation

In valuing the demand for recreation, the literature has grown from using revealed preference methods to applying stated preference methods, namely contingent valuation and choice modelling. Recent attempts have merged revealed and stated preference data to exploit the strengths of both sources of data. We use contingent behaviour and choice experiments data to show that, with choice experiments exercises, when respondents are asked to choose which improvement programme they prefer for a site with recreational opportunities, failing to consider the information explaining the number of visits that respondents intend to take to a recreational site under each hypothetical programme leads to biased coefficients estimates in the models for the choice experiments data.travel cost, contingent behaviour, choice experiments, revealed preferences, stated preferences, Environmental Economics and Policy, Q51, Q26,

Lexicographic Preferences in Discrete Choice Experiments: Consequences on Individual-Specific Willingness to Pay Estimates

In discrete choice experiments respondents are generally assumed to consider all of the attributes across each of the alternatives, and to choose their most preferred. However, results in this paper indicate that many respondents employ simplified lexicographic decision-making rules, whereby they have a ranking of the attributes, but their choice of an alternative is based solely on the level of their most important attribute(s). Not accounting for these simple decision-making heuristics introduces systemic errors and leads to biased point estimates, as they are a violation of the continuity axiom and a departure from the use of compensatory decision-making. In this paper the implications of lexicographic preferences are examined. In particular, using a mixed logit specification this paper investigates the sensitivity of individual-specific willingness to pay (WTP) estimates conditional on whether lexicographic decision-making rules are accounted for in the modelling of discrete choice responses. Empirical results are obtained from a discrete choice experiment that was carried out to address the value of a number of rural landscape attributes in Ireland.Continuity axiom, Discrete Choice Experiments, Lexicographic Preferences, Mixed Logit, Individual-Specific Willingness to Pay

Using Discrete Choice Experiments to Derive Individual-Specific WTP Estimates for Landscape Improvements under Agri-Environmental Schemes: Evidence from the Rural Environment Protection Scheme in Ireland

Reported in this paper are the findings from two discrete choice experiments that were carried out to address the value of a number of farm landscape improvement measures within the Rural Environment Protection (REP) Scheme in Ireland. Image manipulation software is used to prepare photorealistic simulations representing the landscape attributes across three levels to accurately represent what is achievable within the Scheme. Using a mixed logit specification willingness to pay (WTP) distributions based on the parameter estimates obtained from the individual conditional distributions are derived. These estimates are subsequently adjusted and combined to account for baselines and levels of improvement resulting from the implementation of the REP Scheme. Individual-specific WTP estimates are thus obtained for the contribution of the Scheme to rural landscapes and are subsequently contrasted with the average cost of the Scheme across the Irish adult population. Results indicate that the Scheme contributes substantial benefits to rural landscapes.Agri-environment, Discrete choice experiments, Individual-specific WTP, Mixed logit

Attribute processing in environmental choice analysis: implications for willingness to pay

Data from a discrete choice experiment is used to investigate the implications of failing to account for attribute processing strategies (APSs). The research was designed to elicit the economic benefits associated with landscape restoration activities that were intended to remediate environmental damage caused by illegal dumping activities. In this paper we accommodate APSs using an equality constrained latent class model. By retrieving the conditional class membership probabilities we recover estimates of the weights that each respondent assigned to each attribute, which we subsequently use ensure unnecessary weight is not allocated to attributes not attended to by respondents. Results from the analysis provide strong evidence that significant gains in models fit as well as more defensible and reliable willingness to pay estimates can be achieved using when the APSs are accounted for.Attribute processing strategies, environmental restoration, equality constrained latent class model, multinomial logit model, willingness to pay, Environmental Economics and Policy,

Valuing the Recreational Benefits From the Creation of Nature Reserves in Irish Forests

Data from a large-scale contingent valuation study are used to investigate the effects of forest attributes on willingness to pay for forest recreation in Ireland. In particular, the presence of a nature reserve in the forest is found to significantly increase the visitors' willingness to pay. A random utility model is used to estimate the welfare change associated with the creation of nature reserves in all the Irish forests currently without one. The yearly impact on visitors' economic welfare of new nature reserves approaches half a million pounds per annum, exclusive of non recreational values.Non-market valuation, Contingent valuation, Forest attributes analysis, Nature reserves.

12．グルタミン酸ナトリウムはglucagon like peptide-1の食後早期の分泌を促進し, 食後血糖の上昇を抑制する

The purpose of this study was to compare the growth and nutritional status of infants fed different diets, some of whom received a low-fat formula. Beginning at four to six months of age, 101 infants were fed whole cow\u27s milk, one of two low-fat follow-up formulas, or a standard infant formula until 12 months of age. Weight, recumbent length, and head circumference were measured at one-month intervals. Analyses of status (values at an age) for all examinations showed no significant differences among the feeding groups in status for weight or recumbent length, but there were significant differences in head circumference for boys and for girls after adjustments for the initial values. Head circumferences were smaller in those fed whole cow\u27s milk and relatively large in those fed follow-up formula, but these differences were small and not of clinical significance. Comparisons with national reference data showed growth in weight, recumbent length, and head circumference was normal regardless of feeding group. These results indicate that, during the second half year of infancy, the use of lower fat concentrations in the follow-up formulas did not retard growth in weight, recumbent length, or head circumference