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1.
Development of genetically modified (GM) crops is challenging the functions of the grain marketing system. A stochastic optimization model was developed in this study to determine optimal testing strategies. The model chooses the optimal testing strategy that maximizes utility (minimizes disutility) of additional system costs due to testing and rejection, and allows the estimation of the risk premium required for sellers to undertake the dual marketing of GM and non-GM segregations over a non-GM system. Costs are estimated for a vertically integrated grain export chain including testing, rejection, and a risk premium. The model includes elements of costs and risks of adventitious commingling at all stages of the marketing chain, variety declaration, grower truth-telling, and accuracy of testing technologies. Sensitivities were evaluated for the effects of GM adoption, risk parameters, variety declaration, and tolerance levels.  相似文献   

2.
An analytical model was developed to explore prospective costs and risks of alternative testing strategies for a marketing system in Canada which markets both genetically modified (GM) and Non‐GM wheats. The problem is solved using stochastic optimization, base case results are defined, and sensitivities conducted to evaluate impacts of selected variables. Added costs include: testing, rejection, and a risk premium which is required for handlers to be indifferent between the current and the proposed dual system. Protocols would require testing at the point of loading at the primary elevator, and export elevator, and supplementing this information with some form of grower variety declaration. There are several sources of inherent risks in such a system. For buyers, the cumulative impact of these is the risk of receiving GM content in a Non‐GM shipment. For sellers, it is the risk of having a Non‐GM shipment rejected. For sellers, the risk of rejection was typically less than 2%, and for buyers, the risk was typically less than 0.02%. Nous avons élaboré un modèle analytique pour explorer les coûts et les risques potentiels de la mise en place de nouvelles stratégies pour analyser le grain si le Canada décidait de commercialiser du blé génétiquement modifié (GM) et du blé non génétiquement modifié (NGM). Le problème est résolu à l'aide d'une optimisation stochastique; des scénarios de référence sont définis et des tests de sensitivité sont effectués pour évaluer l'impact de variables sélectionnées. Les coûts supplémentaires comprennent les coûts d'analyses, les coûts liés au rejet ainsi qu'une prime de risque exigée pour que les manutentionnaires demeurent indifférents entre le système actuel et le système double proposé. Les protocoles obligeraient la tenue d'analyses au point de chargement du silo primaire ainsi qu'au silo terminal, auxquelles s'ajouterait une certaine forme de déclaration du céréaliculteur sur la variété. Ce genre de système comporte plusieurs sources de risques inhérents. Pour les acheteurs, l'impact cumulatif est le risque de recevoir un chargement de blé NGM contenant du blé GM. Pour les vendeurs, c'est le risque qu'un chargement de blé NGM soit rejeté. Pour les vendeurs, le risque de rejet était généralement inférieur à 2%, et pour les acheteurs, le risque était généralement inférieur à 0.02%.  相似文献   

3.
The introduction of new generation agricultural products has generated an increased need for efficient and accurate product segregation across a number of Canadian agricultural sectors. As a key component of wheat handling in the Canadian grain industry, grading of wheat for value‐added blending has historically been accomplished by visual identification. As of 2008 in Canada, visual identification was eliminated for all primary classes of wheat and replaced by an alternative system of wheat declaration. Given the high costs of testing each truck and railcar for quality assurance, the declaration system must rely on incentives and trust as there is now considerable potential for accidental or opportunistic misrepresentation throughout the grain supply chain. This research attempts to identify cost‐effective handling strategies and policies so as to maintain the integrity of the supply chain under the new declaration system. An agent‐based simulation model is developed to capture the effects of individual heterogeneity as well as behavioral adaption to the declaration system within the modern wheat supply chain. The simulated results are used to identify superior testing strategies for handlers, along with the relative risks and costs associated with each of the testing strategies.  相似文献   

4.
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   

5.
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   

6.
Researchers have often attributed the farm–wholesale price spread, after adjusting for marketing costs, as compensation for marketing firms' risk bearing. However, price spreads in excess of marketing costs can also be due to marketing firms' exercise of market power. In settings where both imperfect competition and marketer risk aversion are plausible, a modeling framework must be sufficiently general to accommodate both types of behavior. This article develops and estimates such a model in the context of fresh produce marketing and develops the implications for analysis of supply‐control programs. The model is applied to the production and marketing of Chinese cabbage in Taiwan and specifically to the analysis of supply‐control programs implemented in this industry by the Taiwanese government. The empirical results provide little support for the hypothesis that marketing firms exhibit risk averse behavior, but they do show that marketing firms exercise oligopsony power in procurement of the product from farmers, and that this power is positively related to the quantity supplied in each market period. This provides a heretofore unexplored impetus for supply controls intended to raise producer incomes. However, such controls are also rendered less effective by imperfect competition because marketing firms capture part of the benefits from supply reduction.  相似文献   

7.
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   

8.
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   

9.
Supermarkets, wholesalers, and tomato growers in Guatemala   总被引:3,自引:0,他引:3  
The article shows the asset‐related determinants and the impacts of the participation of small farmers in supermarkets versus traditional market channels in Guatemala. Compared to farmers selling only to the traditional market channels, farmers selling to supermarket channels are larger (but are in the upper tier of the “small farmer” category), have more capital, and are much more specialized in commercial horticulture in general and in tomatoes in particular. While they have higher yields, they also have higher input use, including use of chemicals. In fact, they severely overuse pesticides and fungicides. Moreover, these greater input expenditures mean that their profit rates are roughly similar to those of farmers in the traditional market channel. Supermarket‐channel farmers prefer the more demanding wholesale‐supermarket channel because it offers lower risks and lower transaction costs to market, a variety of quality grades of tomatoes, all year long. In turn, the supermarkets, who do not buy direct but rather source from a few specialized‐dedicated wholesalers, rely on this year‐round supply, lower transaction costs, and consistency of quality.  相似文献   

10.
This study focuses on how subsidized crop insurance affects crop choices. Crop insurance may change farm investments by reducing risks and providing subsidies. First, actuarially fair insurance reduces risks in crop production and marketing, holding the expected return constant. Second, insurance subsidies encourage farms to purchase crop insurance, which increases the expected return to insured risky crops. Farms also have many self‐insurance mechanisms such as crop diversification or working off the farm. We derive conditions under which (1) unsubsidized and actuarially fair crop insurance or (2) insurance premium subsidies lead to more investment in a risky higher return crop. We then examine the role of self‐insurance for these conditions. The impact of premium subsidies is decomposed into a direct profit effect and an indirect coverage effect. These effects are explained by substitutions between market insurance and self‐insurance and between a risky crop and a safe crop. We discuss each effect as a combination of subsidy and risk effects. Numerical illustrations show that an insurance subsidy has a larger impact on risky crop investments compared to that of an input subsidy when farms are more risk‐averse and have high costs of self‐insurance. The framework provides a novel way to evaluate subsidized crop insurance programs.  相似文献   

11.
This paper builds on the literature on the economic effects of the second‐generation, consumer‐oriented genetically modified products (GMPs). It analyses the market and welfare impacts of the introduction of these new products in markets, like the EU, that mandate the segregation and labelling of the first‐generation, producer‐oriented GMPs. Developing an empirically relevant model of heterogeneous consumers and producers, the study determines the effects of the consumer‐oriented GMPs on the markets of conventional, GM and organic products, and the welfare of consumers and agricultural producers. Analytical results indicate that the market effects of the new GMPs are case specific and depend on: (i) the consumer valuation of the quality‐enhancing attribute of the new GMP; (ii) the level of consumer aversion to GMOs; (iii) the strength of consumer preference for organic products; and (iv) the production costs and marketing margins in the different supply channels. The policy on the labelling of the first‐generation GMPs does not affect the impacts of the second‐generation GMPs on the quantities and market shares of the different products. However, it does affect their price effects and welfare implications. The introduction of consumer‐oriented GMPs under a mandatory labelling regime can result in losses for some GM consumers and all producers of the conventional product.  相似文献   

12.
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   

13.
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   

14.
In many arid and semi‐arid regions whether or not to desalinate seawater has long been a non‐issue and policy debates are focused on the timing and extent of the desalination activities. We analyze how water scarcity and demand structure, on the one hand, and cost reduction via R&D programs, on the other hand, affect the desirable development of desalination technologies and the time profiles of fresh and desalinated water supplies. We show that the optimal R&D policy is of a non‐standard most rapid approach path (NSMRAP) type, under which the state of desalination technology — the accumulated learning from R&D efforts — should approach a pre‐specified target process as rapidly as possible and proceed along it thereafter. The NSMRAP property enables a complete characterization of the optimal water policy. The renewable nature of the fresh water stock permits a non‐monotonic behavior of the optimal stock process: under certain conditions, the stock is depleted, to be fully or partly) refilled at a later date.  相似文献   

15.
Farmers in sub‐Saharan Africa are constrained by large transaction costs associated with marketing of their livestock. However, transaction costs are often not taken into account in the analysis of factors hampering the development of livestock marketing in this region. This article empirically measures the influence of transaction costs on the offtake from cattle grazed on natural rangelands in Uganda. The study is based on the monitoring of 696 cattle transactions in three districts of Uganda from August 2004 to August 2005. The estimated models suggest that proportional transaction costs represented by the state of roads, distance to markets, and time taken to reach the market are important variables constraining market participation. In order to raise offtake from the national herd, it is essential to explicitly address these costs. One potential solution is collective action in marketing of livestock in which proportional and fixed transaction costs are reduced and shared among the group members.  相似文献   

16.
Growth and liberalization of world trade have increased the risks of introduction of quarantine plant pests into importing countries. Import inspection of incoming commodities is a major tool for prevention of pest introductions related to world trade, but inspection capacities are limited. This article develops a theoretical and an empirical model for the optimal allocation of inspection effort for phytosanitary inspection of imported commodities when the inspecting agency has a limited capacity. It is shown that the optimal allocation of inspection effort equalizes marginal costs of pest introduction across risky commodity pathways. The numerical illustration finds the optimal allocation of inspection effort of chrysanthemum cuttings imported in the Netherlands. The numerical results suggest that ceteris paribus , greater inspection effort should be allocated to pathways whose inspection yields a greater reduction in the expected costs of pest introduction. The numerical results also suggest that import inspection has a high marginal benefit. In particular, we found that each additional euro of the inspection capacity decreases the expected costs of pest introduction from 18 to 49 euros, depending on the initial inspection capacity.  相似文献   

17.
The United States (US) exports more than US$6 billion in agricultural commodities to the European Union(EU) each year, but one issue carries the potential to diminish this trade: use of biotechnology in food production. The EU has adopted more stringent policies towards biotechnology than the US. Understanding differences in European and American policies towards genetically modified (GM) foods requires a greater understanding of consumers’ attitudes and preferences. This paper reports results from the first large‐scale, cross‐Atlantic study to analyse consumer demand for genetically modified food in a non‐hypothetical market environment. We strongly reject the frequent if convenient assumption in trade theory that consumer preferences are identical across countries: the median level of compensation demanded by English and French consumers to consume a GM food is found to be more than twice that in any of the US locations. Results have important implications for trade theory, which typically focuses on differences in specialization, comparative advantage and factor endowments across countries, and for on‐going trade disputes at the World Trade Organization.  相似文献   

18.
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   

19.
A seven‐year comparative study of grid pricing versus average pricing of slaughter cattle was conducted to evaluate carcass quality market signals. The primary objectives of the study are to determine: (1) if market signals sent through the grid pricing system indicate an improvement in the grid incentive mechanism over time, (2) how changes in the grid premium and discount structure associated with carcass quality affect the market risk premium, and (3) if changes in price risk (variance) affect producer marketing decisions. An Exponential‐Autoregressive‐Conditional‐Heteroskedasticity‐in‐Mean (EARCH‐in‐Mean) modeling procedure was adopted. Empirical results suggest that the grid premium and discount structure is slowly adjusting carcass quality market signals to encourage marketing on a grid and discourage marketing by the pen. The inclusion of the conditional variance in the empirical model indicates that variance associated with the carcass quality risk premium adds financial risk associated with the adoption of grid pricing.  相似文献   

20.
Pollen‐mediated gene flow is one of the main concerns associated with the introduction of genetically modified (GM) crops. Should a premium for non‐GM varieties emerge on the market, ‘contamination’ by GM pollen would generate a revenue loss for growers of non‐GM varieties. This paper analyses the problem of pollen‐mediated gene flow as a particular type of production externality. The model, although simple, provides useful insights into coexistence policies. Following on from this and taking GM herbicide‐tolerant oilseed rape (Brassica napus) as a model crop, a Monte Carlo simulation is used to generate data and then estimate the effect of several important policy variables (including width of buffer zones and spatial aggregation) on the magnitude of the externality associated with pollen‐mediated gene flow.  相似文献   

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