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51.
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   
52.
Coffee is produced in equatorial and subequatorial regions of the world, which are also most affected by El Niño Southern Oscillation (ENSO). ENSO events have a tendency to amplify weather conditions such as droughts or excess precipitation in the affected regions, resulting in production shortage or excess supply, subsequently impacting agricultural commodity prices. In this research we assess effects of ENSO events on world coffee price dynamics using the monthly data between March 1989 and December 2010. We employ smooth transition autoregression framework to examine nonlinear dynamics of ENSO and coffee prices, and illustrate the results of this research using generalized impulse‐response functions. We find that ENSO events indeed have short‐term impacts on coffee prices. The research findings are of interest to coffee producers and intermediaries in the coffee markets as well as researchers in the fields of environmental and development economics.  相似文献   
53.
征信法规建设的滞后使得中国人民银行分支机构征信工作缺乏法律依据,一定程度上制约了征信执法效能的发挥。为提高征信执法效能,应进一步完善《征信管理条例》并使之尽早出台,加快制定企业征信方面相关办法、《个人信用信息基础数据库管理办法》实施细则和信用评级方面相关办法等。  相似文献   
54.
Soil fertility decline and soil management for crop production are important economic issues for grain growers in north-eastern Australia. In that region, there is evidence of soil fertility decline which is attributed to past crop management practices. The questions addressed in this article are first, whether components of soil fertility can be improved by better management and second, by how much soil fertility would change. Soil fertility for crop production is considered in terms of soil organic carbon and nitrogen. A stochastic dynamic economic analysis of soil fertility management for wheat production is presented. A sequential analysis of first deriving the optimal nitrogen stock and application rates is followed by an assessment of tillage, stubble, and fertilizer strategies to obtain an optimal level of soil organic carbon. The recommended management practices are consistent with emerging management trends in the region. The derivation of optimal levels of soil fertility for agricultural purposes has other policy implications, which we discuss.  相似文献   
55.
The use by farmers of futures contracts and other hedging instruments has been observed to be low in many situations, and this has sometimes seemed to be considered surprising or even mysterious. We propose that it is, in fact, readily understandable and consistent with rational decision making. Standard models of the decision about optimal hedging show that it is negatively related to basis risk, to quantity risk, and to transaction costs. Farmers who have less uncertainty about prices and those with a diversified portfolio of investments have lower optimal levels of hedging. If a farmer has optimistic price expectations relative to the futures market, the incentive to hedge can be greatly reduced. And finally, farmers who have low levels of risk aversion have little to gain from hedging in terms of risk reduction, in that the certainty‐equivalent payoff at their optimal hedge may be little different than the certainty equivalent under zero hedging. These reasons are additional to the argument of Simmons (2002) who showed that, if capital markets are efficient, farmers can manage their risk exposure through adjusting their leverage, obviating the need for hedging instruments.  相似文献   
56.
Recent increases in food and other commodity prices have highlighted concerns that many poor countries are net food importers and higher food prices would worsen their trade balances. In this article, we analyze the changes in food trade balances associated with the 32% increase in food prices from 2000/2001 to 2004/2005. We find a small deterioration in food trade balances of low‐income countries and an improvement in middle‐income countries. The deterioration is most severe for countries in conflict and small island states, so attention should be placed first on these countries and on a few very‐low‐income countries that are also vulnerable. Because low‐income countries as a group had much lower agricultural GDP growth rates than middle‐income countries, the answers to food vulnerability in low‐income countries should probably be addressed within the context of incentives for agricultural production.  相似文献   
57.
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   
58.
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   
59.
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   
60.
Dutch glasshouse firms are facing the introduction of a system of tradable CO2 emission quotas. This paper employs a non‐parametric method for modelling tradable CO2 emissions of Dutch glasshouse firms. The method is capable of generating shifts in CO2 emissions across the sample of firms. Moreover, changes in volumes of outputs produced and inputs used are computed. Results show that firms using a conventional heating technology will be net purchasers of CO2 emissions, whereas firms using more advanced heating technologies will sell part of their emission quota.  相似文献   
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