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1.
Traditional poultry production plays an irreplaceable role in the sustenance of livelihoods in rural Ethiopia. Ironically, however, much has been done to replace indigenous poultry breeds with exotic genetic resources regardless of the importance producers and consumers attach to attributes of the resources. This study aims at informing policy to establish effective indigenous poultry breeding and conservation programs. Discrete choice experiment (DCE) was employed to generate data. Designing of the DCE involved identification, definition, and measurement of attributes of adaptive, productive, and sociocultural importance considering the multiple functions of village chickens. Random parameters logit and the generalized multinomial logit (G‐MNL) models were used to estimate taste parameters. Economic values of traits of chickens were estimated using the utility in willingness‐to‐pay (WTP) space approach, based on G‐MNL model formulation. The results show that important traits of chickens to farmers are mothering ability, diseases resistance, and meat and eggs taste. These findings question the appropriateness, at least in the prevailing production system, of the Ethiopian national government's effort to improve productivity in village poultry by targeting specialized egg‐layer improved chickens. The findings also suggest that poultry breeding programs aiming to provide readily acceptable breed technology by farmers need to prioritize traits of adaptive importance, and mothering ability, instead of focusing on egg productivity only. The key implication is that the unique qualities of the indigenous poultry breeds need to be carefully identified and prioritized before resorting to those that proved to be successful in different production systems.  相似文献   

2.
Data from a farm survey and choice experiment are used to value the benefits of Bt cotton in Pakistan. Unlike previous research on the economic impacts of Bt, which mostly concentrated on financial benefits in terms of gross margins, we also quantify and monetize health and environmental benefits associated with technology adoption. Due to lower chemical pesticide use on Bt cotton plots, there are significant health advantages in terms of fewer incidents of acute pesticide poisoning, and environmental advantages in terms of higher farmland biodiversity and lower soil and groundwater contamination. Farmers themselves value these positive effects at US$ 79 per acre, of which half is attributable to health and the other half to environmental improvements. Adding average gross margin gains of US$ 204 results in aggregate benefits of US$ 283 per acre, or US$ 1.8 billion for the total Bt cotton area in Pakistan.  相似文献   

3.
Choice experiments (CEs) are a relatively new approach to valuing environmental resources. Initial tests of the validity of the approach have either compared benefit estimates generated using CEs with those estimated using contingent valuation (CV) or used more sophisticated hypothesis tests of parameter equality. Although useful, existing tests have been restricted to testing consistency based on a single policy scenario (standard CV). We argue that, although these tests are informative, they fail to take full advantage of the richness of CE data. In particular, CE data allow for the calculation of benefit estimates over a range of policy scenarios (i.e. attribute combinations). A similar range of benefit estimates may be generated by pooling scenarios in a repeated CV study. In this paper, we explore this relationship between CV and CEs by conducting validity tests between a CE model and a repeated CV model over a range of three levels of improved water quality at Clear Lake, IA, USA. Evidence from this test suggests that the CE and CV data are consistent.  相似文献   

4.
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   

5.
Management of livestock diseases is important in ensuring food safety to consumers in both domestic and export markets. Various measures are prescribed under the Sanitary and Phytosanitary Standards (SPS) agreement of the World Trade Organization. In order to prevent the spread of trans‐boundary cattle diseases, the SPS agreement recommends the establishment of Disease‐Free Zones (DFZs). These have been implemented successfully in some major beef‐exporting countries, but in Kenya are still at a pilot stage. To understand Kenyan farmers’ preferences on the type of DFZ that would be readily acceptable to them, a choice experiment was conducted using a D‐optimal design. Results show that farmers would be willing to pay to participate in a DFZ where: adequate training is provided on pasture development, record keeping and disease monitoring; market information is provided and sales contract opportunities are guaranteed; cattle are properly labelled for ease of identification; and some monetary compensation is provided in the event that cattle die due to severe disease outbreaks. Preferences for the DFZ attributes are shown to be heterogeneous across three cattle production systems. We also derive farmers’ preferences for various DFZ policy scenarios. The findings have important implications for policy on the design of DFZ programmes in Kenya and other countries that face similar cattle disease challenges.  相似文献   

6.
In the early 1980s, a paradigm shift occurred in the field of food security, following Amartya Sens (1981) claims that food insecurity is more of a demand concern, affecting the poor's access to food, than a supply concern, affecting availability of food at the national level. Despite the wide acceptance of Sen's thinking, many controversies including the relative importance of supply‐side versus demand‐side variables in causing and solving food insecurity have remained in academic and policy circles. This study develops a recursive household food security model within the framework of consumer demand and production theories following Singh et al. (1986) , and parses out the relative importance of supply‐side versus demand‐side variables in determining household food security in southern Ethiopia. Based on results of a test of full/reduced model and the magnitude of changes in conditional probabilities of food security, we conclude that the supply‐side variables are more powerful determinants of food security than the demand‐side variables.  相似文献   

7.
In this study, we develop a conceptual bioeconomic model of floriculture production with aesthetic benefits, wherein optimal decision rules depend on an intertemporal economic objective to maximize profits subject to economic and biological processes. Necessary conditions of the model identify optimal trajectories (e.g., simultaneous, single, or cycling controls) that define decision rules and economic thresholds for profit maximizing growers producing crops with aesthetic attributes. The necessary conditions also highlight intertemporal trade‐offs between aesthetic benefits and expected future net benefits of arthropod stocks, which have important policy implications. The model is applied to the greenhouse production system of ivy geranium.  相似文献   

8.
This paper analyses the role of risk and rate of time preference in the choice of land contracts. The analysis builds on the risk‐sharing and imperfect market explanations of contract choice. Unique data from Ethiopia, which contain land contract information and experimental risk and rate of time preference measures on matched landlord–tenant partners, are employed in the empirical analysis. The results show that landlord and tenant time preferences are significant determinants of contract choice. For landlords (but not tenants), risk preference is also significant, indicating the importance of financial constraints and production risk in the determination of contract choice. The results are of particular relevance to land market policy in Ethiopia, where production is risk‐prone, financial markets are imperfect, and where there is a major need for the development of vibrant land rental markets.  相似文献   

9.
This research investigates how the public of a middle‐income country, Thailand, values ecosystem services associated with irrigated rice agriculture using a choice experiment. The results show a significant willingness to pay for services such as drought mitigation, water quality and the environment and maintenance of rural lifestyles and rice landscapes. The iterative procedure developed to fully analyze the incidence of attribute nonattendance (ANA) improved the model fit when compared with a multinomial logit model or an ANA model with potentially only one attribute ignored at a time (ANA‐1). Moreover, the inferred probability of the class of respondents having attended all attributes was 45%, compared to 9% with ANA‐1 model. However, it also suggests that 55% of the respondents made their choices by considering only two of the five attributes. Finally, this research also suggests that failing to consider ANA does not change the public ranking of scenarios contrasted by the services they would provide but would overestimate the WTP for these scenarios.  相似文献   

10.
This article investigates the effects of wheat genetic diversity and land degradation on risk and agricultural productivity in less favored production environments of a developing agricultural economy. Drawing production data from a household survey conducted in the highlands of Ethiopia, we estimate a stochastic production function to evaluate the effects of variety richness, land degradation, and their interaction on the mean and the variance of wheat yield. Ethiopia is a center of diversity for durum wheat and farmers manage complex variety mixtures on multiple plots. Econometric evidence shows that variety richness increases farm productivity. Variety richness also reduces yield variability but only for high levels of genetic diversity. Simulations with estimated parameters illustrate how planting more diverse durum wheat varieties on multiple plots contribute to improving farmer's welfare.  相似文献   

11.
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   

12.
Even after controlling for hypothetical biases, some incentive‐aligned value elicitation methods still produce different willingness‐to‐pay (WTP) estimates. In this study, we compare WTP estimates from three incentive‐aligned value elicitation methods: real choice experiment (RCE), real double‐bounded dichotomous contingent valuation (RCVM), and Becker–DeGroot–Marschak auction (BDM). We find that participants’ aggressiveness in obtaining low prices (i.e., “deal‐proneness”) influences WTP estimates in the BDM auction, but not those elicited from the RCE and RCVM. The participants with higher levels of deal‐proneness tend to submit lower bids in the BDM auction. The discrepancies in WTP estimates between different incentive‐aligned procedures are narrower for participants with lower levels of deal‐proneness. Our results indicate that the bids in BDM auctions may be understated and the auction mechanism may induce the “gambling behavior” of people who are deal‐prone. That is, whether the BDM auction is truly incentive‐aligned is again called into question. We also discuss the practical implications for food retailers.  相似文献   

13.
Extreme interannual variability of precipitation within Ethiopia is not uncommon, inducing droughts or floods and often creating serious repercussions on agricultural and nonagricultural commodities. A dynamic climate module is integrated into an economy‐wide model containing a detailed zonal level agricultural structure. This coupled climate‐economic model is used to evaluate the effects of climate variability on prospective irrigation and infrastructure investment strategies, and the ensuing country‐wide economy. The linkages between the dynamic climate module and the economic model are created by the introduction of a climate‐yield factor (CYF), defined at the crop level and varied across Ethiopian zones. Nine sets of variable climate (VC) data are processed by the coupled model, generating stochastic wet and dry shocks, producing an ensemble of potential economic prediction indicators. Analysis of gross domestic product and poverty rate reveal a significant overestimation of the country's future welfare under all investment strategies when climate variability is ignored. The coupled model ensemble is further utilized for risk assessment to guide Ethiopian policy and planning.  相似文献   

14.
Agricultural multifunctionality is the recognition of the joint exercise of economic, environmental and social functions by this sector. Nevertheless, not all these contributions to society are valued in markets, moreover a large share of them are public goods. For this reason, in order to make this concept of multifunctionality operative for the design of public policies, it is necessary to estimate the social demand of such functions. The objective of this article was to implement an empirical application along these lines. For this purpose, the agricultural system of cereal steppes in Tierra de Campos in Spain is taken as a case study. The economic valuation technique used relies on a combined implementation of contingent valuation and the analytical hierarchy process. The results obtained demonstrate the existence of a significant demand for the different attributes included in the multifunctionality concept, although this demand is heterogeneous and is based on the socioeconomic characteristics of individual persons.  相似文献   

15.
In an attempt to identify price stabilization strategies and rationalize public intervention in buffering markets, this article investigates the intertemporal dynamics of commodity prices in Ethiopia. A classical rational expectation model is modified to account for seasonal correlation of shocks. Model predictions are reduced to computable periodic threshold autoregression. Several nonlinearity tests are applied to detect threshold effects. A regime‐switching normalized maximum likelihood method is formulated to estimate thresholds and threshold autoregression parameters using monthly data from Ethiopia for the period 1996–2006. The result indicates the presence of periodic price thresholds that could be formed as a result of speculative storage. Comparison of price movements below and above thresholds indicates that prices are more correlated below the thresholds than above them. However, the effect on error variance is not very strong. Temporal arbitrage, which is the gross return from speculative storage, appears to be modest. The long‐ and short‐term implications of the findings are discussed within the context of ongoing policy debates.  相似文献   

16.
An extensive body of research concerns the valuation of EU certification schemes of quality based on the origin of food products. This literature focuses mainly on stated preferences (SPs) and reported behaviours by the consumers. We combine consumers’ SPs, obtained through a conjoint ranking experiment, with revealed preferences (RP), obtained through a retail scanner database. We evaluate SPs as predictors of RP, and investigate whether SPs and RPs are consistent. Dry‐cured ham in Spain is chosen as the anchor product, mainly because of its broad customer base and long history of origin certification. A ‘trick’ nested logit model with non‐identical and identical samples of consumers is estimated to answer each of the objectives. Results show that, irrespective of the analysed samples, SP can predict general market trends and choices but not accurately predict market shares, and that consumers’ actual behaviour is partly consistent with their SPs. We find that consumers prefer ham produced in Teruel, compared with unspecified Spanish origin. Quality Certification and a Distributor’s Brand are preferred over the alternatives of no quality label or identified with a brand owned by the producer. Interestingly, SPs for the Quality Certification and the distributor’s brand lead to an over‐ and under‐estimation, respectively, of the market share.  相似文献   

17.
This article analyzes households’ choice on tea varieties in Vietnam by using a multinomial logit model. The modeling takes into account the issue of unobserved individual heterogeneity and the endogeneity of some explanatory variables (use of chemical and organic fertilizers). The results show that important factors influencing the decision to adopt one type of tea varieties include income, age, household size, farming contract, and use of organic fertilizers, but also membership of professional associations such as the Tea Association and the Farmers Union.  相似文献   

18.
This study explores consumer acceptance and valuation of a genetically modified (GM) staple food crop in a developing country prior to its commercialization. We focus on the hypothetical introduction of a disease‐resistant GM banana variety in Uganda, where bananas are among the most important staple crops. A choice experiment is used to investigate consumer preferences for various attributes related to the banana (such as bunch size, technology, producer benefit, and price) and examine their opinions on GM foodstuff. Choice data come from 421 banana‐consuming households randomly selected from three regions of Uganda. A latent class model is used to investigate the heterogeneity in consumers’ preferences for selected attributes related to the banana and to profile consumers who are more or less likely to accept GM bananas. Our results reveal that there is significant heterogeneity in consumer preferences across our sample. GM bananas are valued the most by poorer households located in the rural areas of the Eastern region. These food‐insecure households would experience the highest benefits (i.e., welfare gains) from the commercial release of GM bananas. In contrast, urban consumers are less accepting of GM bananas, and they would experience significant welfare losses if GM banana is released. According to our welfare estimates, both the total welfare benefits acquired by the gainers and the total welfare losses borne by the losers of this technology are significant and large. These results suggest the need for further investigation of the overall welfare effects of the introduction of GM bananas on the Ugandan society as a whole.  相似文献   

19.
Climate‐smart agriculture (CSA) is an approach for transforming and reorienting agricultural systems to support food security under climate change. Few studies, however, quantify at the national scale CSA's economic effects or compare CSA to input‐intensive technologies, like fertilizer or irrigation. Such quantification may help with priority setting among competing agricultural investment options. Our study uses an integrated biophysical and economic modeling approach to quantify and contrast the economywide effects of CSA (integrated soil fertility management in our study) and input‐intensive technologies in Ethiopia's cereal systems. We simulate impacts for 20‐year sequences of variable weather, with and without climate change. Results indicate that adopting CSA on 25% of Ethiopia's maize and wheat land increases annual gross domestic product (GDP) by an average 0.18% (US$49.8 million) and reduces the national poverty rate by 0.15 percentage points (112,100 people). CSA is more effective than doubling fertilizer use on the same area, which increases GDP by US$33.0 million and assists 75,300 people out of poverty. CSA and fertilizer have some substitutability, but CSA and irrigation appear complementary. Although not a panacea for food security concerns, greater adoption of CSA in Ethiopia could deliver economic gains but would need substantial tailoring to farmer‐specific contexts.  相似文献   

20.
This study tests the transferability of the nonmarket values of water conservation for domestic and environmental purposes across three south European countries and Australia applying a common choice experiment design. Different approaches are followed to test the transferability of the estimated values, aiming to minimise transfer errors for use in policy analysis, comparing both single‐ and multicountry transfers, with and without socio‐economic adjustments. Within Europe, significant differences are found between implicit prices for environmental water use, but not for domestic water use. In the Australian case study, alleviating restrictions on domestic water use has no significant value. Pooling the three European samples improves the transferability of the environmental flow values between Europe and Australia. Results show that a reduction in transfer error is achieved when controlling for unobserved and observed preference heterogeneity in the single‐ and multicountry transfers, providing additional support for the superiority of socio‐economic adjustment procedures in value transfer.  相似文献   

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