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1.
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   

2.
Adoption of agricultural technology is often sequential, with farmers first adopting a new technology on part of their lands and then adjusting their use of the new technology in later years based on what was learned from the initial partial adoption. Our article explains this experimental behavior by using a dynamic adoption model with Bayesian learning, in which forward‐looking farmers take account of future impacts of their learning from both their own and their neighbors’ experiences with the new technology. We apply the analysis to a panel of U.S. soybean farmers surveyed from 2000 to 2004 to examine their adoption of the genetically modified (GM) seed technology. We compare the results of the forward‐looking model to that of a myopic model, in which farmers maximize current benefits only. Results suggest that the forward‐looking model fits data better than the myopic model does. And potential estimation biases arise when fitting a myopic model to forward‐looking decision makers.  相似文献   

3.
We examine smallholder farmers’ willingness to pay for agricultural technology and whether information is a constraint to adoption of certified maize seed in Northern Uganda. The uptake of improved maize varieties by smallholder farmers in Uganda remains persistently low, despite the higher yield potential compared to traditional varieties. A recently growing body of literature identifies information constraints as a potential barrier to adoption of agricultural technologies. We used incentive compatible Becker‐DeGroot‐Marschak auctions to elicit willingness to pay for quality assured improved maize seed by 1,009 smallholder farmers, and conducted a randomised evaluation to test the effect of an information intervention on farmers’ knowledge of seed certification. Our results show that the randomised information treatment enhanced farmers’ knowledge of certified seed. However, using the information treatment as an instrumental variable for knowledge, we find no evidence of a causal effect of knowledge on willingness to pay, suggesting that even though farmers are information constrained, this constraint does not affect adoption of certified seed directly. Nevertheless, only 14% of sampled farmers were willing to pay the market price, which corresponds closely with actual observed demand for certified seed in the previous season. This suggests that there are other barriers to adoption than information and awareness.  相似文献   

4.
Risk,learning, and technology adoption   总被引:1,自引:0,他引:1       下载免费PDF全文
This article explores how decision makers learn and use information, with an application to the adoption of biotechnology in agriculture. The empirical analysis relies on experimental and survey data measuring risk preferences, learning processes, and the adoption of genetically modified (GM) seeds among U.S. grain farmers. While controlling for risk aversion, we link individual learning rules with the cognitive abilities of each decision maker and their actual GM adoption decisions. We find evidence that very few individuals are Bayesian learners, and that the population of farmers is quite heterogeneous in terms of learning rules. This suggests that Bayesian learning (as commonly assumed in the analysis of agricultural technology adoption) is not an appropriate characterization. In addition, we do not find a strong relationship between observed learning styles and the timing of GM seed adoption. To the extent that learning is a key part of the process of technology adoption, this suggests the presence of much unobserved heterogeneity in learning among farmers.  相似文献   

5.
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   

6.
Dry‐land legumes, well adapted to drought‐prone areas, have largely been neglected in the past despite the good opportunities they offer for income growth and food (and nutritional) security for the poor. This study evaluated the adoption and impact of two farmer and market‐preferred and disease‐resistant pigeonpea varieties that were developed and promoted in semi‐arid Tanzania. The new varieties were resistant to fusarium wilt, a fungal disease devastating the crop. However, farmers wanting to adopt new varieties did not adopt due to seed access constraints and under‐developed seed delivery systems. Adoption of new varieties is therefore analyzed using an augmented double hurdle model that allows estimating variety adoption conditional on seed access thresholds accounting for the additional information on sample separation. The study identifies the crucial role of seed access (local supply), extension, education, participatory decision making, capital, and household assets in determining adoption. The social economic benefits of the technology and policies for improved seed access were further analyzed using the extended economic surplus method (DREAM model). Even under restrictive assumptions, overall discounted benefits were found to be quite attractive, indicating the need for additional efforts to scale‐up the success story. Analysis of changes in research benefits from relaxing the seed access constraint showed that net gains would increase by up to 30% if farmer access to improved seeds can be assured. Smallholder farmers are the major beneficiaries along with consumers and rural net‐buyers who gain from productivity‐induced lower market prices.  相似文献   

7.
The potential impact of climate change on Taiwan's agriculture   总被引:1,自引:0,他引:1  
This paper intends to estimate the potential impact of climate change on Taiwan's agricultural sector. Yield response regression models are used to investigate the climate change's impact on 60 crops. A price‐endogenous mathematical programming model is then used to simulate the welfare impacts of yield changes under various climate change scenarios. Results suggest that both warming and climate variations have a significant but non‐monotonic impact on crop yields. Society as a whole would not suffer from warming, but a precipitation increase may be devastating to farmers.  相似文献   

8.
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   

9.
This study was carried out to assess cotton farmers’ willingness to pay (WTP) for pest management services in northern Benin. Targeted staggered control (TSC) has been introduced to reduce pesticide use in cotton cropping and generate an estimated benefit of FCFA48,800 (€74.40) per cotton hectare accruing from increased productivity and reduced pesticide cost. However, TSC application requires extra time for pest identification and scouting, and its adoption remains low due to the lack of funding to boost farmers’ awareness and cover training costs. An interval regression model was used to analyze responses to a double‐bounded contingent valuation survey with data collected from 300 cotton farmers. The results showed that 87.3% of cotton farmers were willing to pay for TSC services. Annual WTP per cotton hectare was estimated at FCFA16,962 (€25.80), revealing an existing demand for TSC adoption. Respondents' WTP was driven by farm and socio‐economic characteristics. Financial mechanisms managed by farmers could thus potentially foster technology adoption, and in turn, generate economic and environmental benefits.  相似文献   

10.
Double blind field experiments and experimental auctions were conducted with bean and cowpea farmers in Tanzania and Ghana to gauge the relative demand for three types of seed products that differ in price and quality: certified, quality declared, and recycled. Whether the cost differential makes these seeds qualitatively different products as reflected in their perceived performance, and whether that translates into farmers’ willingness to pay price premiums, are the research questions addressed by this study. Results indicate that, all else equal, there were significant differences in the perceived quality of the seed products evaluated. Farmers were willing to pay significantly more for their higher rated seed relative to their lower rated seeds. However, for a majority of farmers the magnitude of the premium they are willing to pay for a higher quality seed is less than the current price differential between certified seed and grain. Research and policy implications of these results for legume seed system are discussed.  相似文献   

11.
This article examines the magnitude and sources of yield variation among adopters of improved cowpea varieties in northern Nigeria promoted through farmer‐to‐farmer diffusion. The results reveal important efficiency differences between the lead farmers who have contacts with breeders and the follower farmers who get technology and information from the lead farmers. Differential adoption of the package of seed, insecticide, fertilizer, and recommended cereal‐cowpea cropping pattern provides much of the explanation for yield variation among adopters. The component often missing, and hence accounting for much of the yield variation, is the crop management technology relating to the cereal‐cowpea cropping pattern. No efficiency variation is attributed to the source of technology and information, such as whether improved cowpea was obtained from breeders or lead farmers. Technology source has a rather indirect influence on efficiency through its effect on package adoption where breeders promote greater package adoption among the lead farmers than the lead farmers do among the follower farmers. Possible ways of disseminating crop management technological information through the farmer‐to‐farmer technology diffusion are recommended to better exploit the yield and profitability potentials of improved cowpea varieties in northern Nigeria.  相似文献   

12.
Kenya is a globally recognized maize “success story.” As the overall percentage of maize farmers growing hybrids tops 80% and the seed industry matures, the slow pace of hybrid replacement on farms, and the continued dominance of the seed industry by Kenya Seed Company, may dampen productivity. Our econometric analysis identifies the factors that explain farmer demand for hybrid seed, and the age of hybrids they grow, considering hybrid seed ownership. Male‐headed households with more education, more assets, and more land plant more hybrid seed. Scale of seed demand per farm is differentiated by agroecology. We find a strong farmer response to the seed‐to‐grain price ratio, which we interpret as evidence of a commercial orientation even on household farms. However, despite the dramatic increase in the number of hybrids sold and the breadth of seed suppliers as seed markets liberalize, an older hybrid still dominates national demand.  相似文献   

13.
In 2013, Ethiopia's Agricultural Transformation Agency introduced the Wheat Initiative to increase smallholder productivity. In this article, we measure the impacts of the Wheat Initiative package of technologies, and its marketing assistance component alone, on yields among a promotional group of farmers. The package includes improved techniques, improved inputs, and a guaranteed market for the crop. Relying on crop‐cut measures and farmers’ own assessments, we find that full package led to an average 14% higher yields. Implementation of the Wheat Initiative was successful in making certified seed and fertilizer accessible to farmers and increasing their uptake, though only 61% of the intervention group adopted row planting and few farmers received marketing assistance. The measured yield difference may underestimate the true yield difference associated with the technology because of incomplete adoption of the recommended practices by intervention farmers and adoption of some practices by control farmers.  相似文献   

14.
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   

15.
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   

16.
In India, pearl millet is a typical subsistence crop. Nonetheless, use of hybrid seeds is widespread. The first pearl millet hybrids were introduced in 1965 by the public sector. Yet, starting in the late 1980s, market liberalisation led to an increasing role of private companies in seed development and distribution. Although several studies showed that proprietary pearl millet hybrids are more productive than public hybrids and open‐pollinated varieties, the impacts of privatisation on farmers’ technology access and overall innovation rates are not yet well understood. This paper analyses the dynamics of adoption using duration models and farm survey data collected in the state of Maharashtra. The results show that education, short distances to main information sources and good market infrastructure speeded up the adoption of pearl millet hybrids. Likewise, the increasing role of private seed companies had a positive and accelerating effect on technology diffusion in the small farm sector.  相似文献   

17.
With the decline of cotton especially in the marginal cotton areas, farmers have been using more of the cotton‐financed inputs on the cereals. The cotton para‐statal company (CMDT) has made a virtue out of this recommending diversification for these regions. Following the world price spike in 2010, the Malian government responded with a substantial price increase for cotton in 2011 of 38% to rejuvenate the Malian sector. This article looks at the impact of this price policy in the cotton economy and the potential of new cereal technology and marketing strategy to raise incomes and facilitate the diversification. Given the importance of the marketing decision of selling later after the recovery of cereal prices from the harvest collapse, a discrete stochastic programming model was developed for three‐stage decision making. Then, the recent changes in the cotton economy and government fertilizer subsidies were analyzed along with the introduction of the new technology marketing of sorghum. Cotton and maize continue to dominate the economy but the combined sorghum technology marketing increases farmers’ incomes by 16% to 21% and eases the return to normal cotton prices, after the 2011 price spike, as well as the removal of the fertilizer subsidies.  相似文献   

18.
The current article explores the characteristics that distinguish early from late adopters of GM corn and measures the productivity impacts of early adoption, for a sample of farmers in Minnesota and Wisconsin. The results of the adoption analysis confirm that size, education as well as specialization are positively correlated with early adoption. In addition, these results also show that farms that are mostly worked by family labor but hire some off‐farm labor are more likely to adopt GM seeds earlier in the diffusion process. The productivity analysis demonstrates the superiority of stacked varieties. At the same time, we find no evidence of a direct impact of experience on yields. Given the previously documented impact of early adoption on the use of stacked varieties, we conclude that experience plays a role through the adoption of these new technologies but does not play a role in allowing the producer to use the technology more efficiently, once it has been adopted.  相似文献   

19.
Agricultural diversification and integrated pest management in Bangladesh   总被引:1,自引:0,他引:1  
We study factors associated with a shift toward diversified, high‐valued vegetable crops and the incentives associated with the use of IPM methods for vegetable producers in Bangladesh. The primary objective is to measure how IPM technologies affect the crop and technology choices of low‐income rice farmers. A three‐season household optimisation model is used to study crop and technology choice under price and yield uncertainty. The model is parameterised using data from vegetable farms and experimental IPM trials conducted in Bangladesh. Simulation results show that access to IPM technology and IPM availability combined with access to credit increase household welfare and lead to higher rates of vegetable adoption. Off‐farm employment opportunities work against vegetable cultivation and IPM use by risk‐averse farmers. Implications for policy and extension efforts are highlighted.  相似文献   

20.
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   

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