首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
This study evaluates the impact of a long‐term research collaboration between the Senegalese Institute for Agriculture Research (ISRA), and the Bean/Cowpea Collaborative Research Support Program (CRSP) funded by the U.S. Agency for International Development (USAID). Adoption of the primary outputs from this collaboration, a nonchemical cowpea storage method and two short‐season cowpea varieties, were tracked through a series of farmer interviews in 1996, 1997, and 2004 in the main cowpea growing area of Senegal. Combined with information from an impact assessment in the late 1980s, this study draws on ex‐post adoption data from most of the product life cycle for the storage technology. The 2004 survey found that 60.4% of cowpea production in the main cowpea growing area of Senegal is stored in metal drums and that 69% of households use this storage technology; ISRA/CRSP improved short season varieties were determined to account for 3.6% of cowpea production. Baseline economic analysis of the most recent survey data, which includes benefits and costs of the storage technology and improved varieties, reveal an IRR to donor funding of 13%. The benefits of these technologies appear to be evenly distributed in the rural population on the basis of gender and ethnic background. Comparison of the rates of technology adoption over time, however, reveals that use of the storage technology may be decreasing; inclusion of this technology disadoption trend reduces the IRR by only 0.4% from the baseline estimate. Overall, estimated returns reveal that this collaboration has been a good investment for the U.S. and Senegalese governments, and other donors.  相似文献   

2.
The impact of social networks on hybrid seed adoption in India   总被引:4,自引:0,他引:4  
This article adds to the literature about the impact of social networks on the adoption of modern seed technologies among smallholder farmers in developing countries. The analysis centers on the adoption of hybrid wheat and hybrid pearl millet in India. In the local context, both crops are cultivated mainly on a subsistence basis, and they provide examples of hybrid technologies at very different diffusion stages: while hybrid wheat was commercialized in India only in 2001, hybrid pearl millet was launched in 1965. The analysis is based on surveys of wheat and millet farmers in the state of Maharashtra. Comprehensive data on farmer characteristics and social interactions allow for identifying individual networks, thereby improving upon previous research approaches that employed village-level variables as proxies for network effects. Using econometric models, we find that individual social networks play an important role for technology adoption decisions. While village-level variables may be used as suitable proxies at later diffusion stages, they tend to underestimate the role of individual networks during early phases of adoption.  相似文献   

3.
Understanding what determines the geographic spread of innovations can help guide the funding and implementation of research and extension programs. Our approach uses household survey data as model parameters, to simulate behavior across the entire surveyed population and avoid the aggregation bias associated with representative‐farm models. Such a “heterogeneous agent” approach allows us to infer the distribution of a technology's impacts across one set of households, and predict the potential for spreading to another set that shares similar characteristics with respect to natural resource endowments and farming systems. We apply the technique to new cassava varieties in West Africa, finding a strongly poverty‐alleviating impact, with substantial spillover potential from Nigeria to neighboring countries.  相似文献   

4.
The article analyzes how controlling for differences in land types (defined by position on a low‐scale toposequence) affects estimates of farm technical efficiency for rice farms in eastern India. Contrasting previous research, we find that farms are considerably more technically efficient when efficiency estimates are carried out at the plot level and control for plot characteristics rather than at the farm level without such controls. Estimates show farms cultivating modern varieties are technically efficient and plots planted with traditional varieties on less productive lands (upland and midupland) operate close to the production frontier. Significant technical inefficiency is found on more productive lands (medium and lowland plots) planted with traditional rice varieties. The finding that these smallholder rain‐fed rice farms are efficient cultivators on some plots contrasts with previous findings of farm‐level inefficiency (i.e., rejects overarching explanations linked to farm operator ignorance or lack of motivation) and suggests more complex explanations are required to address the inefficiency that is present.  相似文献   

5.
Sustainable agricultural intensification is an urgent challenge for Sub-Saharan Africa. One potential solution is to rely on local farmers' knowledge for improved management of diverse on-farm resources and integration among various farm enterprises. In this article, we analyze the farm-level impact of one recent example, namely the integrated aquaculture–agriculture (IAA) technologies that have been developed and disseminated in a participatory manner in Malawi. Based on a 2004 survey of 315 respondents (166 adopters and 149 nonadopters), we test the hypothesis that adoption of IAA is associated with improved farm productivity and more efficient use of resources. Estimating a technical inefficiency function shows that IAA farms were significantly more efficient compared to nonadopters. IAA farms also had higher total factor productivity, higher farm income per hectare, and higher returns to family labor.  相似文献   

6.
This article shows that the observed sample adoption rate does not consistently estimate the population adoption rate even if the sample is random. It is proved that instead the sample adoption rate is a consistent estimate of the population joint exposure and adoption rate, which does not inform about adoption per se. Likewise, it is shown that a model of adoption with observed adoption outcome as a dependent variable and where exposure to the technology is not observed and controlled for cannot yield consistent estimates of the determinants of adoption. The article uses the counterfactual outcomes framework to show that the true population adoption rate corresponds to what is defined in the modern policy evaluation literature as the average treatment effect (ATE), which measures the effect or impact of a "treatment" on a person randomly selected in the population. In the adoption context, a "treatment" corresponds to exposure to the technology. The article uses the ATE estimation framework to derive consistent nonparametric and parametric estimators of population adoption rates and their determinants and applies the results to consistently estimate the population adoption rates and determinants of the NERICA (New Rice for Africa) rice varieties in Côte d'Ivoire. The ATE methodological approach developed in the article has significant policy implications with respect to judging the intrinsic merit of a new technology in terms of its potential demand by the target population independently of issues related to its accessibility and in terms of the decision to invest or not in its wide-scale dissemination.  相似文献   

7.
Agroclimatic conditions and agricultural research and development (R&D) including plant breeding activities by the public sector are some of the most significant exogenous factors in the agricultural sector. However, the effects of the interactions between these two sets of factors on agricultural productivity have not been studied widely in developing countries, despite potentially important implications on their plant breeding strategies. Using three‐wave panel data of agricultural households in Nigeria and spatial data on various agroclimatic parameters, we show that agricultural productivity and technical efficiency at the agricultural household level is significantly positively affected by the similarity of agroclimatic conditions between locations where agricultural households are located, and locations where major plant breeding institutes are located. These results hold after controlling for various socioeconomic characteristics of these households, including their physical distances to the breeding institutes. Findings are robust across parametric and nonparametric specifications such as Data Envelopment Method, and after addressing potential endogeneity of agroclimatic similarity and agricultural inputs variables in the production function. Productivity effects due to the locations of plant breeding institutes and resulting agroclimatic similarity can be potentially sizable given Nigeria's past productivity growth speed.  相似文献   

8.
This study employs the propensity score matching model to examine the impact of the adoption of water conservation and intensification technologies on farm output and income among small-scale lowland rice farmers in the Northern Region of Ghana. The matching was conducted based on the Mahalanobis distance combined with the propensity score. Balancing tests by checking the mean standardized absolute bias in the matched sample were conducted as well as a sensitivity analysis was conducted to check for hidden bias due to unobservable selection. The empirical results show a positive and significant impact of the adoption of bunds technology on input demand as well as a positive but insignificant impact on output supply and net returns. Adopters of the dibbling technology were found to have higher output supply, whereas no statistically significant difference was found between the incomes of adopters and nonadopters of dibbling seed method. The results, however, reveal a positive and significant effect on output and net returns when the dibbling method is combined with intensified weeding. The estimates were found to be relatively insensitive to hidden bias.  相似文献   

9.
10.
There is a lack of evidence for impact at scale of vegetable research and development, although the importance of vegetables for human nutrition and smallholder incomes is generally understood. We therefore study adoption and impact of improved tomato and African eggplant varieties developed through international agricultural research, released by national agricultural research and extension systems, and supplied to farmers by private seed companies in East and Southern Africa from 1990 to 2014. The study finds that in 2014, varieties developed by the World Vegetable Center accounted for 50% of tomato and 98% of African eggplant commercial seed production in East and Southern Africa. For Tanzania alone, investment in crop improvement generated economic gains of US$ 255 million for tomato and US$ 5 million for African eggplant up to 2014. The internal rate of return is 26% for tomato and 12% for African eggplant, though we project the latter to increase to 26% by 2024 as the variety was released only in 2007. These findings support the view that agricultural policy and investment reoriented towards contemporary nutritional challenges will give high returns to investment.  相似文献   

11.
This article attempts to integrate the production‐ and the efficiency‐based approaches for evaluating the impact of extension on farms' performance. For this purpose the nonneutral production frontier model is used, and the empirical analysis refers to a sample of farms from Crete, Greece. The empirical results support the proposed formulation instead of either the production‐ or the efficiency‐based formulations as extension was found to have a statistically significant effect on closing both the technology and management gaps. Public and private extension services were found to be competitive in the production function and complementary in the technical inefficiency effect function. In addition, farms using both public and private extension services achieved a higher degree of technical efficiency than those using either public or private extension services, and farms with no extension services were found to be the least efficient.  相似文献   

12.
We hypothesize that hog production can be characterized by complementarities between new technologies, worker skills, and farms size. Such production processes are consistent with Kremer's O‐ring production theory in which a single mistake in any one of several complementary tasks in a firm's production process can lead to catastrophic failure of the product's value. In hog production, mistakes that introduce disease or pathogens into the production facility can cause a total loss of the herd. Consistent with predictions derived from the O‐ring theory, we provide evidence that the most skilled workers concentrate in the largest and most technologically advanced farms and are paid more than comparable workers on smaller farms. These findings suggest that worker skills, new technologies, and farm size are complements in production. The complementarities create returns to scale to large hog confinements, consistent with the dramatic increase in market share of very large farms over the past 20 years.  相似文献   

13.
Limited empirical evidence exists on how multiple binding constraints influence the adoption of improved technologies by smallholder farmers. This article uses the case of groundnut variety adoption in Uganda to investigate the role of information, seed supply, and credit constraints in conditioning technology uptake. New data from a household survey in seven groundnut growing districts (n = 945) indicate that 8% of farmers lack information on new varieties, while 18% and 6% of farmers, respectively, cannot adopt mainly due to seed supply and capital constraints. A tobit‐type specification that considers all nonadopters as being uninterested in the technology (i.e., corner solutions) would lead to inconsistent parameter estimates and incorrect conclusions in this context. We therefore estimate a modified multi‐hurdle specification of demand for new varieties, taking into account how information, seed supply, and capital constraints jointly determine adoption probability and intensity. The study reveals new empirical insights on why agricultural technology adoption in Africa has lagged behind: slow uptake is not mainly due to a lack of economic incentives, but rather a reflection of information, seed supply, and credit constraints that prevent farmers from translating their desired demand into adoption of modern varieties. Policy implications are discussed.  相似文献   

14.
There have been sharp increases in nonfarm income among farm households in Central Luzon for the last few decades. This study attempts to identify the effects of the increasing nonfarm income on the use of tractors and threshers and on the employment of hired labor as a substitute for family labor. We found that while the increased nonfarm income positively affects the ownership of tractors, it has no significant impact on the use of agricultural machines due presumably to the development of efficient machine rental markets. We also found that the increased nonfarm income leads to the increased use of hired labor, thereby releasing family labor to nonfarm jobs.  相似文献   

15.
This paper evaluates the effect of the Rural Capacity Building Project (RCBP), which aimed at promoting growth by strengthening the agricultural service systems in Ethiopia, and by making them more responsive to smallholders’ needs, in particular women farmers. We examine the gender‐differentiated impact of the RCBP using panel data on 1,485 geographically dispersed households in project and control kebeles. We find that women farmers’ access and satisfaction with extension services increased significantly immediately after the start of the project, but that effect did not last into the medium term. The project led to an increase in the adoption of high‐value crop farming, area of land cultivated, and economic participation of household members, benefiting male‐ and female‐headed households equally. Results point to the positive impact of incorporating women's needs and constraints in the design of the agricultural extension system. However, the project was not able to reduce the preexisting gender gap in agricultural outcomes.  相似文献   

16.
This study uses an agent‐based model for ex ante assessment of agricultural innovations. The model builds on whole farm mathematical programming (MP) and extends the methodology with a spatial representation of the system, the heterogeneity of farm households and landscapes, and the interaction between farm households. We apply the model in a northern Thai watershed to study the potential of four innovations to increase the profitability of litchi orchards. Cost‐benefit analysis shows that each innovation would increase the profitability of litchi growing; however, the results of the agent‐based model show that at current price levels these innovations alone would not be enough to stem the decline in the area under litchis. The model was validated and the sensitivity of the results tested for variations in the irrigated water supply and liquidity. We report on how farmers responded to these results and discuss the implications for other areas in northern Thailand.  相似文献   

17.
The decoupling of direct payments from production introduced in the reform of the Common Agricultural Policy is expected to make production decisions more market‐oriented and farmers more productive. However, ex‐post analyses of the productivity of farms have yet to uncover any evidence of a positive impact of the decoupling policy on farm productivity. Using Irish, Danish, and Dutch farm‐level data, we identify whether the decoupling policy has contributed to productivity growth in agriculture and farm product adjustment behavior. We find some evidence that the decoupling policy had significant positive effects on farm productivity and behavioral changes related to farm specialization.  相似文献   

18.
Biofortified staple foods are currently being developed to reduce problems of micronutrient malnutrition among the poor. This partly involves use of genetic modification. Yet, relatively little is known about consumer acceptance of such second‐generation genetically modified (GM) foods in developing countries. Here, we analyse consumer attitudes towards provitamin A GM cassava in the north‐east of Brazil. Based on stated preference data, mean willingness to pay is estimated at 60–70% above market prices for traditional cassava. This is higher than the results from similar studies in developed countries, which is plausible given that micronutrient malnutrition is more severe in developing countries. GM foods with enhanced nutritive attributes seem to be well received by poor consumers. However, the results also suggest that acceptance would be still higher if provitamin A were introduced to cassava through conventional breeding. Some policy implications are discussed.  相似文献   

19.
Classical innovation adoption models implicitly assume homogenous information flow across farmers, which is often not realistic. As a result, selection bias in adoption parameters may occur. We focus on tissue culture (TC) banana technology that was introduced in Kenya more than 10 years ago. Up till now, adoption rates have remained relatively low. We employ the average treatment effects approach to account for selection bias and extend it by explicitly differentiating between awareness exposure (having heard of a technology) and knowledge exposure (understanding the attributes of a technology). Using a sample of Kenyan banana farmers, we find that estimated adoption parameters differ little when comparing the classical adoption model with one that corrects for heterogeneous awareness exposure. However, parameters differ considerably when accounting for heterogeneous knowledge exposure. This is plausible: while many farmers have heard about TC technology, its successful use requires notable changes in cultivation practices, and proper understanding is not yet very widespread. These results are also important for other technologies that are knowledge‐intensive and require considerable adjustments in traditional practices.  相似文献   

20.
This article aims to evaluate the impact of the 2005 reform of the Common Agricultural Policy (CAP) on farm production choices as a treatment effect (TE). This impact is measured through alternative metrics of the short‐term changes of the output vector. The heterogeneity of the response to the reform is assessed by estimating both average and quantile TE. As this heterogeneous response may depend on the different farm‐level CAP support, a multivalued treatment approach is adopted and applied to treated units (i.e., supported farms). This approach is applied to a balanced panel of Italian FADN farms observed over years 2003–2007. Results show that the 2005 reform of the first pillar of the CAP actually had an impact in (re)orienting short‐term farm production choices but this response is largely heterogeneous and concentrated in the lower levels of support.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号