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1.
Serial non-participation is a response behavior that is frequently found in stated choice experiments. One form of serial non-participation is that a varying number of respondents chooses always the zero-price or status quo alternative. The approaches used in the literature to deal with this problem vary from excluding those respondents to using applying latent class models to endogenously allow for different preference structures. However, latent class models also allow to assign respondents to a known class. In this paper we compare specifications of latent class models with and without restrictions. Additionally, we control for differences in the error variance across respondents by applying a scale-extended latent class model. The comparisons are designed to show whether respondents are allocated differently among classes and whether willingness to pay estimates are affected significantly. The data are from a choice experiment regarding management actions to enhance forest biodiversity. The data set is characterized by a high percentage of respondents who were not willing to pay; almost 50% of the respondents always chose the zero price alternative locating this sample rather at the top of the range of respondents who are not willing to pay.  相似文献   

2.
In this paper we present results from two choice experiments (CE), designed to take account of the different negative externalities associated with pesticide use in agricultural production. For cereal production, the most probable impact of pesticide use is a reduction in environmental quality. For fruit and vegetable production, the negative externality is on consumer health. Using latent class models we find evidence of the presence of preference heterogeneity in addition to reasonably high willingness to pay (WTP) estimates for a reduction in the use of pesticides for both environmental quality and consumer health. To place our WTP estimates in a policy context we convert them into an equivalent pesticide tax by type of externality. Our tax estimates suggest that pesticide taxes based on the primary externality resulting from a particular mode of agricultural production are a credible policy option that warrants further consideration.  相似文献   

3.
4.
This study employs mixed logit and latent class models to examine preferences for cattle traits with a focus on heterogeneity among cattle keepers, using choice experiment data of 506 cattle-keeping households in Kenya and Ethiopia. The findings indicate the existence of preference heterogeneity based on cattle production systems. Highly valued cattle traits for the cropping systems include traction fitness and trypanotolerance, while traits associated with herd increase are considered important in pastoral systems. Considering heterogeneity within population segments provides a framework for adapting breeding policy interventions to specific producer segments, by integrating preferred traits in a breed improvement program.  相似文献   

5.
Agricultural applications of nanotechnology are at a relatively early stage and little is known about consumer responses to the technology. Canadian consumer responses to food nanotechnology are examined through the lens of the Food Value Scale. Data from a survey of Canadian consumers are used to evaluate the relative importance of eleven food values to food purchase decisions. We find that taste, safety, nutrition, and price are among the most important food values to Canadians, however, consumers exhibit considerable heterogeneity with respect to the priority placed on these values. A discrete choice experiment (DCE) explores the effect of food values on choice behavior. The DCE is positioned as a sliced apple product with non-browning and antioxidant-enhanced features introduced through the use of nanocoating or a conventional coating method. Random parameters logit (RPL) and latent class models (LCM) confirm the existence of significant preference heterogeneity. The LCM identifies three classes of consumers: “supporters,” “doubters,” and “opponents” who differ in their reaction to nanotechnology and in the relative importance placed on food values such as naturalness, novelty, and convenience. The analysis shows that food values provide additional insights into consumers’ food choices and their attitudes toward novel food technologies.  相似文献   

6.
In an effort to improve productivity and profits, many farmers have replaced traditional livestock breeds with higher yielding alternatives. While such changes may bring about short‐term economic gains, the loss of traditional livestock breeds could result in the loss of an important genetic resource as a variety of important genetic traits adapted to local conditions gradually become less common in the population. This is a particular problem in Africa, where livestock make a substantial contribution to human livelihoods. Using the example of cattle in Kenya's pastoral livestock markets this study uses a choice experiment approach to investigate buyers' preferences for indigenous breeds such as the Maasai Zebu. The analysis employs a latent class approach to characterize heterogeneity in valuations both within and across respondents buying cattle for breeding, slaughter, or resale. The results show that there are at least three classes of buyers with distinct preferences for cattle traits and that most buyers favor exotic rather than indigenous breeds. Such preferences have implications for the conservation of indigenous cattle in Kenya and in other developing countries and suggest that some form of intervention may be required to ensure the preservation of this important animal genetic resource.  相似文献   

7.
Agri‐environmental schemes (AES) have had a limited effect on European agriculture due to farmers’ reluctance to participate. Information on how farmers react when AES characteristics are modified can be an important input to the design of such policies. This article investigates farmers’ preferences for different design options in a specific AES aimed at encouraging nitrogen fixing crops in marginal dry‐land areas in Spain. We use a choice experiment survey conducted in two regions (Aragón and Andalusia). The analysis employs an error component random parameter logit model allowing for preference heterogeneity and correlation amongst the non‐status quo alternatives. Farmers show a strong preference for maintaining their current management strategies; however, significant savings in cost or increased participation can be obtained by modifying some AES attributes.  相似文献   

8.
Benefit transfer is a cost-effective method for estimating the value of environmental goods that relies on information obtained in previous studies. The multiattribute approach of choice experiments should provide advantages in terms of benefit transfer, allowing differences in environmental improvements between sites as well as differences in socioeconomic and attitude characteristics between respondent populations. This article investigates the capability of choice experiment method to be used in environmental benefit transfer when a random parameters approach is used to allow for preference heterogeneity: we find that the inclusion of respondents' taste heterogeneity reduces the magnitude of the transfer error.  相似文献   

9.
One hundred and eighty farmers in the semiarid Makueni district, Kenya, were surveyed using a structured questionnaire. The objective was to assess factors that influence farmers' preference for alternative veterinary service providers following the liberalization of veterinary services. A proportional hazard model was fitted to the data because of its ability to accommodate simultaneously the attributes of both the chooser and the choice. Of the three service providers considered in the study, community‐based animal health workers were the most preferred followed by veterinary surgeons and animal health assistants. Farmers' age and education level were inversely but significantly related to the probability of choosing any of the three service providers. Distance to the preferred service provider was the main choice‐specific attribute with a significant impact on the choice probability. A high preference for community‐based animal health workers was noted suggesting the possibility of poorly trained animal health workers dominating the veterinary services market in remote areas of Kenya. Efforts geared toward the legalization of community‐based animal health workers in Kenya and elsewhere in the developing countries should first address the constraints that hinder the penetration of professional veterinary service providers in remote areas.  相似文献   

10.
We report the results of a study based on revealed and stated preference data on choice of Prosecco wines in retail stores close to the origin of production in Northern Italy. Emphasis is placed on ability to reconcile the utility structure of stated preference data with that underlying revealed preference data. We extend the analysis to cover nonattendance of key attributes, such as price and certification of origin, while controlling for the large range of brand effects.  相似文献   

11.
This study explores the effect of various information processing strategies specifically related to attribute nonattendance in stated choice experiments. Our approach includes two forms of stated choice task nonattendance, each derived from separately framed questions asked immediately following the completion of each choice task. We also evaluate a measure of inferred serial nonattendance based on the posterior distributions of random coefficient estimates. We find that choice task nonattendance question framing statistically impacts marginal utility coefficients and, to a lesser degree, willingness‐to‐pay estimates. While direct questions addressing attribute attendance or nonattendance affect these estimates, inferred indicators of serial nonattendance suggest that many attributes are not likely ignored as often as respondents may indicate. Further research is needed to assess inferred versus stated approaches to modeling respondent information processing strategies.  相似文献   

12.
Farmland can confer significant public good benefits to society aside from its role in agricultural production. In this article, we investigate preferences of rural residents for the use of farmland as a recreational resource. In particular, we use a choice experiment to determine preferences for the development of farmland walking trails. Our modelling approach uses a series of mixed logit models to assess the impact of alternative distributional assumptions for the cost coefficient on the welfare estimates associated with the provision of the trails. Our results reveal that using a mixture of discrete and continuous distributions to represent cost heterogeneity leads to a better model fit and lower welfare estimates. Our results further reveal that Irish rural residents show positive preferences for the development of farmland walking trails in the Irish countryside.  相似文献   

13.
Most literature in landscape perception and preference has focused on aesthetic preference by (groups of) people. Factors that could influence the aesthetic preference, such as landscape dimensions and observer's background characteristics, are far less examined. This may be due to the increasing complexity of the dataset, when variation both in landscape attributes and respondents’ characteristics is to be included in the models. The complex multivariate analysis models that emerge require more sophisticated statistical analysis. Also, the conclusions that result from the traditional analysis sound like, e.g. experts show lower preferences than nonexperts, which is rather deterministic and leaves no room for fuzziness. Latent class analysis provides an opportunity to include fuzziness, by only probabilistically assigning respondents in a latent class in function of the respondent's characteristics. The present paper explores the use of latent class analysis to determine individual differences in the importance appended to several landscape dimensions for landscape aesthetic preference. A questionnaire survey was executed in a spatially stratified sample amongst inhabitants of the city of Ghent (Flanders, Belgium). Latent preference classes are identified of which the cases vary in the level of importance attached to landscape characteristics for aesthetic preference. Care and disturbance appear to have larger effect on preference than naturalness and urbanisation. The effect of care and disturbance on landscape aesthetic preference also most significantly distinguishes between the latent preference classes. The importance of openness for aesthetics is small and not significantly dependent on the individual background of the observer. Respondents’ characteristics that affect the probability of belonging to a latent preference class are environmental behaviour and attitude, actual living environment, age class, education level, and organisation membership. Understanding the basis for differences in landscape preference may respond to tastes and aspirations of the general public, putting landscape planning in the broader context of society.  相似文献   

14.
This article examines two issues concerning the trip–taking behavior of recreational anglers over the course of a season. The first is whether the random component of trip utility is serially correlated across trip occasions. The second is the heterogeneity of preferences among anglers. Recent research has examined heterogeneity among recreational trip–takers using random parameters models. In this article, the population of anglers is, instead, cast as a collection of several subpopulations distinguished by angler preferences, and the method of finite mixtures is used to identify these subpopulations.  相似文献   

15.
In this paper, we apply random utility modelling techniques to rock‐climbing in Scotland. Attributes relevant to choices over rock‐climbing sites were identified from focus groups with climbers, along with a categorisation of principal climbing areas. A survey of climbers yielded 267 responses, which were then used as the basis for modelling. We compare a standard multi‐nominal logit model with a random parameters approach, and look at seasonal differences in behaviour, and at the implications of different treatments of travel time. The random utility models showed that most of the attributes selected were significant determinants of choice. Welfare estimates of changes in site attributes are presented, which are relevant to policy choices currently facing land managers.  相似文献   

16.
Land degradation in the form of soil erosion and nutrient depletion presents a threat to food security and sustainability of agricultural production in many developing countries. Governments and development agencies have invested substantial resources to promote soil conservation practices as part of an effort to improve environmental conditions and reduce poverty. However, limited rigorous empirical work has been done on the economics of soil conservation technology adoption. This article investigates the impact of stone bunds on value of crop production per hectare in low and high rainfall areas of the Ethiopian highlands using cross-sectional data from more than 900 households, with multiple plots per household. We have used modified random effects models, stochastic dominance analysis (SDA), and matching methods to ensure robustness. The parametric regression and SDA estimates are based on matched observations obtained from the nearest neighbor matching using propensity score estimates. This is important, because conventional regression and SDA estimates are obtained without ensuring that there actually exist comparable conserved and nonconserved plots on the distribution of covariates. We use matching methods, random effects, and Mundlak's approach to control selection and endogeneity bias that may arise due to correlation of unobserved heterogeneity and observed explanatory variables.
We find that the three methods tell a consistent story. Plots with stone bunds are more productive than those without such technologies in semi-arid areas but not in higher rainfall areas, apparently because the moisture conserving benefits of this technology are more beneficial in drier areas. This implies that the performance of stone bunds varies by agro-ecology type, suggesting the need for designing and implementing appropriate site-specific technologies.  相似文献   

17.
In this study, we evaluate the preference of consumers in Niger for different tuwo or couscous characteristics using a random utility‐based choice experiment, ordered probit analysis, and tree‐based partitioning. Data were collected through a structured survey administered at four sites. Preferences are estimated for three products (couscous, fermented tuwo, and nonfermented tuwo) made from five pearl millet cutivars. We provide relative valuation for different traits by type of product. Results show that product taste, color, and textural attributes are important, especially for tuwo and couscous. Probit and partitioning results show that taste and color are the first attributes that consumers use to distinguish more preferred millet food products from less preferred millet food products. This should provide some direction for millet breeding programs and food processing of millet.  相似文献   

18.
A random‐coefficients specification of an output distance function is used to measure and decompose productivity growth in German dairy farming. This specification can accommodate heterogeneity with respect to the technology employed by dairy farms, allowing for specialised and non‐specialised farms to be included in the analysis. The proposed modelling approach is favoured by the data when compared with the conventional translog specification of distance functions. The average total factor productivity growth rate for German dairy farms is estimated at 1.1%, with the technical progress component contributing most of this growth.  相似文献   

19.
The search for improved water pricing is central to urban water reform in many countries. Establishing efficient water prices is notoriously difficult, not least because different customers have different demands for water and yet they are presently faced with a one-size-fits-all approach to pricing and service. This is especially challenging where water availability fluctuates widely, as is the case in many parts of Australia, because the impacts of exposure to episodic periods of scarcity can differ markedly. There is now substantial interest in the notion of ‘unbundling’ the water product to provide a better fit between customers' preferences and the level of service received. Following this trend, this study provides important insights into householders' willingness to pay for a range of flexible water options using a choice experiment. The paper reports a relatively underemployed extension to the latent class modelling framework to investigate preference heterogeneity towards urban water products, including purchasing services that involve the provision of environmental and amenity outcomes. The work adds to studies that use choice data to reveal heterogeneity while improving our understanding of household customers' demands. Overall, it also brings into focus questions about the future management of water in urban contexts.  相似文献   

20.
Biodiversity, landscape aesthetics and grazing livestock have considerable relevance for agricultural production, however rarely considered in public landscape preferences research. This paper studies public preferences for pasture usage by the means of a discrete choice experiment using a representative sample of 449 individuals from Germany. Graphical representations of the choice sets were used to assess the preferences for the presence of livestock and typical pasture landscape elements. To account for preference heterogeneity, the paper utilised a latent-class logit model. Four different latent classes were identified. The results showed different preferences between the latent classes, not only in terms of the magnitude of the estimated parameters, but also in terms of the parameter signs. This indicated that there are multiple types of preferred pasture landscapes. Within the groups, the preference for livestock presence did not depend on its density. Furthermore, it was found that point elements were more important for the landscape preference than linear elements. The class membership probabilities were influenced by multiple sociodemographic variables, including the individual’s residence.  相似文献   

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