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1.
Evaluating the possible benefits of the introduction of genetically modified (GM) crops must address the issue of consumer resistance as well as the complex regulation that has ensued. In the European Union (EU), this regulation envisions the co‐existence of GM food with conventional and quality‐enhanced products, mandates the labelling and traceability of GM products and allows only a stringent adventitious presence of GM content in other products. All these elements are brought together within a partial equilibrium model of the EU agricultural food sector. The model comprises conventional, GM and organic food. Demand is modelled in a novel fashion, whereby organic and conventional products are treated as horizontally differentiated but GM products are vertically differentiated (weakly inferior) relative to conventional ones. Supply accounts explicitly for the land constraint at the sector level and for the need for additional resources to produce organic food. Model calibration and simulation allow insights into the qualitative and quantitative effects of the large‐scale introduction of GM products in the EU market. We find that the introduction of GM food reduces overall EU welfare, mostly because of the associated need for costly segregation of non‐GM products, but the producers of quality‐enhanced products actually benefit.  相似文献   

2.
This paper explores farmers’ willingness to adopt genetically modified (GM) oilseed rape prior to its commercial release and estimates the ‘demand’ for the new technology. The analysis is based upon choice experiments with 202 German arable farmers. A multinomial probit estimation reveals that GM attributes such as gross margin, expected liability from cross pollination, or flexibility in returning to conventional oilseed rape significantly affect the likelihood of adoption. Neighbouring farmers’ attitudes towards GM cropping and a number of farmer and farm characteristics were also found to be significant determinants of prospective adoption. Demand simulations suggest that adoption rates are very sensitive to the profit difference between GM and non‐GM rape varieties. A monopolistic seed price would substantially reduce demand for the new technology. A monopolistic seed supplier would reap between 45% and 80% of the GM rent, and the deadweight loss of the monopoly would range between 15% and 30% of that rent. The remaining rent for farmers may be too small to outweigh possible producer price discounts resulting from the costs of segregating GM and non‐GM oilseed rape along the supply chain.  相似文献   

3.
How much might the potential economic benefit from enhanced farm productivity associated with crop biotechnology adoption by Australia and New Zealand (ANZ) be offset by a loss of market access abroad for crops that may contain genetically modified (GM) organisms? This paper uses the Global Trade Analysis Project (GTAP) model to estimate effects of other countries' GM policies without and with ANZ farmers adopting GM varieties of various grains and oilseeds. The gross economic benefits to ANZ from adopting GM crops under a variety of scenarios could be positive even if the strict controls on imports from GM‐adopting countries by the European Union are maintained, but not if North‐East Asia also applied such trade restaints. From those gross economic effects would need to be subtracted society's evaluation of any new food safety concerns and negative environmental externalities (net of any new environmental and occupational health benefits), as well as any extra costs of segregation, identity preservation and consumer search.  相似文献   

4.
The unintended presence of traces of genetically modified (GM) crops in the harvests of non‐GM crops plays a prominent role in the debate over the coexistence of GM and non‐GM crops. One way to address the issue is the formation of GM‐free or GM‐only clubs. We model the decisions of individual farmers to cultivate either GM or non‐GM crops and combine this with a game theoretic model of club formation to investigate the feasibility of such clubs. We consider two liability regimes: GM farmers are liable or they are not. We consider two benchmarks: Nash equilibrium without negotiations and the efficient allocation and compare those with partial co‐operation through a Coasean club. We find that in both regimes a relatively large club can form but they are not always necessary to reach the efficient allocation. In fact, if farmers can freely decide under profit maximisation what to cultivate, they reach 95% of an efficient allocation. This holds independent of the property rights system and provides strong support for coexistence policies based on ex‐post liability such as in the US and Spain.  相似文献   

5.
This paper develops a model of differentiated consumers to examine the consumption effects of genetic modification (GM) under alternative labelling regimes and segregation enforcement scenarios. Analytical results show that if consumers perceive GM products as being different than their traditional counterparts, GM affects consumer welfare and, thus, consumption decisions. When the existence of market imperfections in one or more stages of the supply chain prevents the transmission of cost savings associated with the new technology to consumers, GM results in welfare losses for consumers. The analysis shows that the relative welfare ranking of the ‘no labelling’ and ‘mandatory labelling’ regimes depends on: (i) the level of consumer aversion to GM products; (ii) the size of marketing and segregation costs under mandatory labelling; (iii) the share of the GM product in total production; and (iv) the extent to which GM products are incorrectly labelled as non‐GM products.  相似文献   

6.
A stochastic optimization model was developed to determine optimal testing strategies, costs, and risks for dual marketing of genetically modified (GM) and non‐GM wheat in an export supply chain. The optimal testing strategy is derived that minimizes disutility of additional system costs due to testing and quality loss. Cost components were estimated including those related to testing, quality loss, and a risk premium to induce shippers to undertake dual marketing as opposed to handling only non‐GM crops. Uncertainties were incorporated for adventitious presence and commingling, variety declaration, and test accuracy. Sensitivities were performed for effects of variety risks and declaration, penalty differentials, buyer tolerances, risk aversion, and GM adoption. Results indicate testing and segregation can be performed at a relatively low cost and risk to buyers.  相似文献   

7.
While much effort has been devoted to estimating market premiums for non‐genetically modified (GM) food, the results of such research are largely silent about the preferences for the public good aspects, or externalities, of GM food production. For public goods, the closest substitute of private consumption decisions is voting on referenda. In November 2005, 55.7% of 2 million Swiss voters approved a five‐year moratorium (ban) on the commercial cultivation of GM plants in Switzerland. The present study examines how individual voting decisions were determined by: (i) socioeconomic characteristics; (ii) political preference/ideology; and (iii) agreement with a series of arguments in favour and against the use of GM plants in Swiss agriculture. The analysis is based on the data of the regular voter survey undertaken after the national‐level voting in Switzerland. The results suggest that current concerns about the use of genetically engineered plants in agriculture may not automatically decrease with higher levels of education/knowledge and generational change. Furthermore, analysis of voter motives suggests that public support for a ban on GM crops may be even larger in other countries, where industrial interests in crop biotechnology are less pronounced.  相似文献   

8.
Opponents of the voluntary labelling scheme for genetically modified (GM) food products often argue that consumers have the “right to know” and therefore advocate mandatory labelling. In this article, we argue against this line of reasoning. Using experimental auctions we show that the quality of the signal generated by a mandatory labelling scheme is affected by the number of labels in the market. If there are two labels, one for GM products and one for non‐GM products, mandatory and voluntary labelling schemes generate a similar degree of uncertainty about the quality of products that do not carry a label.  相似文献   

9.
High transaction costs and an absence of institutional infrastructure in developing countries prevent comprehensive enforcement of intellectual property rights and generate obstacles to the adoption of genetically modified (GM) crop technology. Governments of developing countries that are members of the World Trade Organization are faced with two options when licensing GM crop technology: (1) attempt to regulate GM crops to the standards of the Agreement on Trade‐Related Aspects of Intellectual Property (TRIPS) or (2) allow a black market in GM seeds and risk trade retaliation from the GM innovator's host country through a TRIPS trade complaint. This paper develops a conceptual model that frames the adopting country's range of licensing options, including a new levy system, and derives welfare measures for each option. The model illustrates how a levy on GM technology can be a welfare‐increasing policy for developing countries, and the operation of a levy is discussed. The conceptual model is applied to Brazil's soybean market and quantitative economic surplus measures are estimated within a calibrated welfare model for a range of licensing scenarios. The model's results suggest that a levy may interfere with the long‐term prospects for innovators to collect monopoly rents in adopting countries.  相似文献   

10.
Two of the experimental methods used to estimate willingness‐to‐pay (WTP) for a non‐market good, the Becker‐DeGroot‐Marschak (BDM) mechanism and the non‐hypothetical choice experiment (nHCE) often lead to significantly different WTP estimates, complicating the choice between the methods. In Zambia the same group of researchers used both techniques to evaluate WTP for orange maize, which provides more vitamin A than other varieties. This provided an opportunity to analyse the sources of the difference. In the BDM experiment, one group of respondents was provided with more training opportunities than the other, and made higher bids. Accounting for lexicographic behaviour in the nHCE reduced the estimated WTP. These two design factors together resulted in a decrease in the WTP difference for orange maize (1,279–632 ZMK) although the difference remains statistically significant. More training was also shown to eliminate the effects of different orders in which maize varieties were presented.  相似文献   

11.
This study investigates heterogeneous consumer preferences for nanofood and genetically‐modified (GM) food and the associated benefits using the results of choice experiments with 1,117 US consumers. We employ a latent class logit model to capture the heterogeneity in consumer preferences by identifying consumer segments. Our results show that nano‐food evokes fewer negative reactions compared with GM food. We identify four consumer groups: ‘Price Oriented/Technology Adopters’, ‘Technology Averse’, ‘Benefit Oriented’, and ‘New Technology Rejecters’. Each consumer group has a distinctive demographic background, which generates deeper insights into the diversified public acceptance of nano‐food and GM food. Our results have policy implications for the adoption of new food technologies.  相似文献   

12.
Some argue that the lack of modern agricultural development in the former socialist countries of Central and Eastern Europe has made cutting‐edge biotechnology attractive. However, enthusiasm for planting genetically modified (GM) crops varies greatly in the enlarged European Union (EU) and especially among the New Member States (NMS); the Czech GM maize area is progressively growing whereas Hungary imposed a de facto ban on GM crops. Remarkably, the Hungarian ban was not supported by any cost–benefit assessment. In the literature, ex ante impact assessments of monopolistically priced technologies are often based on cross‐sectional comparisons of average cropping budgets. Such assessments ignore heterogeneity of farmers and underestimate the true impact of these technologies because of homogeneity bias. Therefore, we propose an improved method by explicitly modelling farmer heterogeneity under imperfect information, and assess the potential value and benefit sharing of GM crops in the two NMS using a stochastic partial equilibrium model. The total potential value of GM crops is estimated at €82 million for both countries, of which €60 million (73%) accrues to farmers and €22 million (27%) to the gene developers and the seed industry. This is in line with the literature on global benefit sharing of first‐generation GM technologies.  相似文献   

13.
In this paper, we generalise existing approaches to the treatment of stated attribute non‐attendance data in discrete choice experiments by allowing attribute specific impacts. We implement this approach by employing an extended hierarchical Bayes logit model specification. To illustrate this approach, we consider data collected to examine Indian consumers’ preferences for traditional aromatic rice varieties. Our results regarding stated attribute non‐attendance reveal that, our new approach shrinks marginal utilities of non‐attenders substantially compared to stated attenders, with significant differences in the shrinkage between some of the attributes. In addition, our results reveal the way in which non‐attendance of attributes interact with each other and the impact that this has on the distribution of willingness to pay estimates.  相似文献   

14.
Genetically modified (GM) crops are popular in many regions of the world, but their deployment in Africa is hindered by safety concerns and regulatory issues, although the continent is in dire need of boosting its food production. Although consumers' acceptance of GM food has been analyzed in many continents, no such studies have been conducted in Africa. Therefore, a survey of 604 consumers was conducted in Nairobi, Kenya, in 2003, to gauge consumers' awareness of GM crops, their willingness to pay (WTP) for GM food, and the factors that influence their WTP. Consumers' knowledge of GM crops was limited and only 38% of the 604 respondents were aware of GM crops. People in higher education and income groups were more aware than others. Regardless, people were generally appreciative of the technology, and a large majority (68%) would be willing to buy GM maize meal at the same price as their favorite brand. Consumers were, however, concerned about possible side effects, especially on the environment and biodiversity. WTP was estimated using a double‐bounded dichotomous choice model, and the mean WTP was found to be 13.8% higher than the average price of non‐GM maize meal. Perceptions of health risk, and ethical and equity concerns had a negative influence on the likelihood of purchasing GM maize meal, whereas trust in government to ensure food quality had a positive influence on WTP. People with at least some secondary education and those in the high‐income category were more likely to purchase GM maize meal at the same price. The study concludes that, because awareness is still low, appropriate communications are needed to involve the consumer in the debate. Consumers' acceptance in this study was high, but the research needs to be expanded to rural areas, where most consumers live, and other survey methods need to be explored.  相似文献   

15.
We investigate consumer demand for genetically modified (GM) rice in urban China, using a relatively large survey of urban consumers in 2013 and the contingent valuation method. Our results show that respondents discount their WTP for first, second and third generation of GM rice by 31%, 34% and 36%, respectively, compared with non‐GM rice, indicating substantial aversion to GM rice by Chinese consumers. The level of consumers’ subjective knowledge of GM rice has a significantly negative impact on their WTP for GM rice, implying that GM rice in China has become a ‘special food’ with an unreliable image.  相似文献   

16.
Policy makers, journalists and other commentators have hailed genetically modified (GM) crops as a ‘pro‐poor’ success in the developing world. Their confidence appears to be justified by the encouraging conclusions reached by academic studies on the performance and impacts of GM crops, which seem to provide convincing evidence of substantial benefits for smallholders in developing countries. However, a detailed, critical examination of studies on transgenic, insect‐resistant cotton in China, India and South Africa demonstrates that the technology's impacts have been evaluated and represented in selective and misleading ways. The performance and impacts of GM crops have in fact been highly variable, socio‐economically differentiated and contingent on a range of agronomic, socio‐economic and institutional factors. The shortcomings of the GM crop‐impacts literature have done a disservice to public and policy debates about GM crops in international development and impeded the development of sound, evidence‐based policy.  相似文献   

17.
Implementation of the Water Framework Directive (WFD) represents a fundamental change in the management of water in Europe with a requirement that member states ensure ‘good ecological status’ for all water bodies by 2015. Agriculture is expected to bear a major share of WFD implementation costs as it is compelled to reduce the emission of diffuse water pollutants. The research outlined here comprises interdisciplinary modelling of agricultural land use, hydrology and consequent water quality effects to consider both agricultural costs and the non‐market recreational use (and potentially non‐use) values that implementation of the Directive may generate. A theme throughout the research is the spatial distribution of the costs and benefits of WFD implementation, which is addressed through the use of GIS techniques in the modelling of agricultural land use, the integration of land use and hydrological models, and the estimation, aggregation and transfer of the economic value of the benefits.  相似文献   

18.
In the continuing debate over the impact of genetically modified (GM) crops on farmers of developing countries, it is important to accurately measure magnitudes such as farm‐level yield gains from GM crop adoption. Yet most farm‐level studies in the literature do not control for farmer self‐selection, a potentially important source of bias in such estimates. We use farm‐level panel data from Indian cotton farmers to investigate the yield effect of GM insect‐resistant cotton. We explicitly take into account the fact that the choice of crop variety is an endogenous variable which might lead to bias from self‐selection. A production function is estimated using a fixed‐effects model to control for selection bias. Our results show that efficient farmers adopt Bacillus thuringiensis (Bt) cotton at a higher rate than their less efficient peers. This suggests that cross‐sectional estimates of the yield effect of Bt cotton, which do not control for self‐selection effects, are likely to be biased upwards. However, after controlling for selection bias, we still find that there is a significant positive yield effect from adoption of Bt cotton that more than offsets the additional cost of Bt seed.  相似文献   

19.
The water reforms undertaken in the Murray–Darling Basin, Australia since 2007 have been viewed as a model for other countries seeking to respond to water insecurity. Here, a policy review is provided of this water reform and whether it delivers on key environmental objectives in the 2007 Water Act (the Act). The evaluation includes a review of the 2012 Basin Plan, a key instrument of the Act, and complementary policies associated with the acquisition of water entitlements for the environment via direct (reverse tenders) and indirect (infrastructure subsidies) means. Using the objects of the Act as a benchmark, an evaluation is provided of the following: (i) planned reductions in irrigation water extractions in the 2012 Basin Plan; (ii) risks associated with the 2018 amendments to the Basin Plan that, collectively, allow for an increase in irrigation water extractions of some 22 per cent, relative to the sustainable diversion limits specified in the 2012 Basin Plan; (iii) Basin‐scale environmental outcomes achieved, as of the end of 2018; and (iv) economic effects of direct and indirect methods of acquiring water for the environment. Findings from the review generate the “Do's” and “Do Nots” of water reform for Australia, and possibly other countries, when managing the trade‐offs between water for irrigation and the environment.  相似文献   

20.
Landscape Clubs: Co-existence of Genetically Modified and Organic Crops   总被引:1,自引:0,他引:1  
The possibility of increased production of genetically modified (GM) crops in agriculture accentuates the need to examine the feasibility of GM and non‐GM technologies co‐existing on a common physical landscape. Using the theory of clubs, this paper examines the possibility of co‐existence for GM and organic wheat technologies through the formation of an organic club with an endogenously determined buffer zone. Given the available data on prices, and yields, it is shown that a club can be created in which GM and organic agricultural production technologies can economically co‐exist in the same physical landscape. Specifically, co‐existence results in an increase in economic welfare over a situation where only GM technology is used but is not Pareto superior because producers in the buffer zone will incur injury. We show that organic producers in the club can compensate producers in the buffer zone and still be better off. Hence, the compensation principle holds. La possibilité de production accrue de cultures génétiquement modifiées (GM) accentue la nécessité d'examiner la faisabilité de coexistence des technologies GM et non GM dans un même paysage agricole. À l'aide de la théorie des clubs, le présent article a examiné la possibilité de coexistence des technologies de culture de blé GM et de blé biologique en créant un club ?biologique? comprenant une zone tampon déterminée de façon endogène. Compte tenu des données disponibles concernant les prix et les rendements, il est montré qu'il est possible de créer un club au sein duquel les technologies de production de cultures biologiques et GM peuvent économiquement coexister dans un même paysage naturel. Spécifiquement, la coexistence engendre une augmentation du bien‐être économique par rapport à une situation où seule la technologie GM est utilisée, mais elle n'est pas Pareto supérieure parce que les producteurs dans la zone tampon subiront des dommages. Nous montrons que les producteurs de cultures biologiques membres du club peuvent indemniser les producteurs de la zone tampon tout en demeurant en bonne position. Le principe de compensation tient donc.  相似文献   

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