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31.
We study the optimal timing of adoption of a cleaner technology and its effects on the rate of growth of an economy in the context of an AK endogenous growth model. We show that the results depend upon the behavior of the marginal utility of environmental quality with respect to consumption. When it is increasing, we derive the capital level at the optimal timing of adoption. We show that this capital threshold is independent of the initial conditions on the stock of capital, implying that capital-poor countries tend to take longer to adopt. Also, country-specific characteristics, as the existence of high barriers to adoption, may lead to different capital thresholds for different countries. If the marginal utility of environmental quality decreases with consumption, a country should never delay adoption; the optimal policy is either to adopt immediately or, if adoption costs are “too high”, to never adopt. The policy implications of these results are discussed in the context of the international debate surrounding the environmental political agenda.   相似文献   
32.
随着互联网的普及,以信息技术改造传统银行业务和开展网上银行服务己成为银行业发展的必然趋势。整合技术接受模型与任务-技术匹配模型,构建了我国个人网上银行服务的采纳模型,并采用结构方程模型方法对影响我国个人用户采纳网上银行服务的因素进行了实证研究。研究结果表明,任务-技术匹配通过感知有用性和感知易用性正向显著影响个人用户对网上银行服务的使用意愿;感知有用性正向影响使用意愿的作用大于感知易用性;而感知风险与结构保证对使用意愿的影响不显著。  相似文献   
33.
This paper examines relationships between crop insurance and input technology decisions among Chilean wheat farmers. Using nationwide farm‐level data, a bivariate probit model is estimated. We investigate the extent to which the adoption of production input technologies is associated with farmers’ participation in the insurance program. We find that relationships between insurance and technology decisions are significant only for family farmers. In particular, there is a negative relationship between participation in the insurance program and the adoption of modern irrigation. Interpretations based on the role of input technologies on insurance adoption and adverse selection behaviours are discussed.  相似文献   
34.
While it is often recognised that agricultural technology adoption decisions are intertwined and best characterised by multivariate models, typical approaches to examining adoption and impacts of agricultural technology have focused on single technology adoption choice and ignored interdependence among technologies. We examine farm‐ and market‐level impacts of multiple technology adoption choices using comprehensive household survey data collected in 2010/11 and 2012/13 in Ethiopia. Economic surplus analysis combined with panel data switching endogenous regression models are used to compute the supply shift parameter (K‐shift parameter), while at the same time controlling for the endogeneity inherent in agricultural technology adoption among farmers. We find that our improved technology set choices have significant impacts on farm‐level maize yield and maize production costs, where the greatest effect appears to be generated when various technologies are combined. The change in maize yield and production costs results in an average 26.4% cost reduction per kilogram of maize output (the K‐shift parameter). This increases the producer and consumer surpluses by US$ 140 and US$ 105 million per annum, respectively. These changes in economic surplus help to reduce the number of poor people by an estimated 788 thousand per year. We conclude that deliberate extension efforts and other policies that encourage integration of technologies are important for maize technologies to yield their full potential at both farm and market levels.  相似文献   
35.
We examine factors affecting the adoption of improved cassava varieties of 217 households in the Cauca Department in southwest Colombia. Using DNA fingerprinting through Single Nucleotide Polymorphisms (SNPs), we identified different cultivars in farmers fields. We also used this information to remove possible bias in the adoption model that could have resulted from a misclassification of improved varieties (IVs). As a result, we found that farmers substantially overestimate their use of IVs and there are important differences in the determinants of adoption between farmer self‐identification and DNA fingerprinting. This finding implies that the incorporation of DNA fingerprinting in IV adoption studies is important to ensure the accuracy of future agricultural economic research and the relevance of subsequent policy recommendations.  相似文献   
36.
Tef is the most important crop in Ethiopia and is well-adapted to growing environments, but grain yields are low. The government is therefore promoting the adoption of improved varieties, inorganic fertilizers and new planting techniques. This study gathered information on the use of new agronomic practices and barriers to their adoption through a semi-structured questionnaire administered to 60 farmers or respondents from each of 4 districts of Tigray region in northern Ethiopia viz Laelay-Maichew, Medebay-Zana, Ahferom and Alamata. Data were coded and analysed using SPSS software. Except for animal feed and crop rotation, there were significant differences between districts in the relative importance of several criteria for different uses. Improved varieties were used by the majority of respondents in all districts and fertilizers in all except Alamata where severe moisture stress dictated the choice of variety and reduced fertilizer application. Weed control was mainly by hand except in Alamata where chemical control was common because of the predominance of broad-leaved weeds. Transplanting maximized the yield of tef, but a cost–benefit analysis showed that row sowing was more profitable. The study concluded that new varieties better adapted to the likelihood of reduced rainfall and that respond efficiently to fertilizer inputs need to be developed. Until suitable technologies are available, high labour costs would in part dictate some agronomic practices, even if this led to lower yields.  相似文献   
37.
Even though diversified agroforestry systems can provide sustainable livelihoods and a resilient production of different goods, adoption remains limited in Bolivia. We examine major obstacles to agroforestry adoption and possible incentives proposed by farmers and civil-society organizations, and relate them to governance and international mechanisms that might play a role in agroforestry adoption. Market access for produce from diversified agroforestry remains difficult, as does its processing and transport. Moreover, farmers have difficulties in achieving the quantities and homogenous quality demanded by markets in the major cities. But most importantly, farmers and civil-society organizations saw little government support, although ‘ecological production in harmony with Mother Earth’ is prescribed by law and the constitution. Agroforestry farmers needed support most urgently in the initial phase, when investment costs are high and returns low. They suggested affordable credits, subsidies for diversified farming systems, and insurance against fire. We identified important albeit small steps towards developing markets for agroforestry products, but government support – mostly in the form of diesel subsidies, materials, and infrastructure – mainly benefitted large-scale monocultures and cattle ranching. In response to this, interviewees opted for strengthening farmers’ organizations, for demanding support with the help of civil-society organizations, and for disseminating best practices.  相似文献   
38.
Export agriculture offers potentially high returns to smallholder farmers in developing countries, but also carries substantial market risk. In this article we examine the intertemporal welfare impact of the timing of a farmer's entry into the export pineapple market in southern Ghana. We examine whether farmers who never cultivated pineapple are better or worse off than farmers who decided to adopt pineapple earlier or later relative to their peers and experienced a significant adverse market shock several years prior to our endline survey. We use a two‐stage least squares model to estimate the causal effect of duration of pineapple farming on farmer welfare. Consistent with economic theory, we find that earlier adoption of the new crop brings greater welfare gains than does later uptake. But we find that the gains to later uptake of pineapple—just before the market shock—are small in magnitude, just 0.1 standard deviations of a comprehensive asset index, indicating that the gains to adoption may be precarious and depend on the context, in particular on the severity of prospective market shocks.  相似文献   
39.
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   
40.
The impacts of adopting agricultural innovation and technology are widely examined. This paper synthesises 154 studies, which yielded a total of 600 estimates of the impact of adopting agricultural innovation and technology on production, social and economic outcomes. Using meta‐regression analysis, the empirical results show that the reported impact of adopting agricultural innovation and technology rises significantly over time, notwithstanding a significant publication bias. Whether studies find significant impacts of adopting agricultural innovation and technology depends on the use of experimental research designs, parametric method, endogenous switching regression and region. Our results show a large bias in the literature towards agricultural innovations and technologies that focus on high‐yielding varieties and thus, neglect other forms of complementary innovations and technologies.  相似文献   
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