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91.
This article uses a novel experimental approach to measure consumer willingness to pay (WTP) for wine attributes. We invited customers of a local supermarket who had selected a bottle of wine to purchase to participate in a valuation experiment. Integrating their original wine choice into the experiment, each participant evaluated six alternative wines, generating a rich set of data on willingness to pay and consumer characteristics. The data from the experiment allow us to compare standard shelf price‐based wine attribute valuation estimates with estimates using WTP data and an increasing amount of information about individual consumers. The full model employs individual fixed effects to estimate WTP parameters without bias from consumer sorting or supply side influences. Our WTP estimates for wine attributes differ markedly from previous attribute value estimates. Consumers in our sample display clear and stable preferences for wine varieties, but less clear preferences for appellations. Our results suggest caution is needed in using market prices to estimate parameters of the consumer valuation function for product attributes.  相似文献   
92.
We develop methods for inference in nonparametric time-varying fixed effects panel data models that allow for locally stationary regressors and for the time series length T and cross-section size N both being large. We first develop a pooled nonparametric profile least squares dummy variable approach to estimate the nonparametric function, and establish the optimal convergence rate and asymptotic normality of the resultant estimator. We then propose a test statistic to check whether the bivariate nonparametric function is time-varying or the time effect is separable, and derive the asymptotic distribution of the proposed test statistic. We present several simulated examples and two real data analyses to illustrate the finite sample performance of the proposed methods.  相似文献   
93.
The Women, Infants, and Children (WIC) Program is considered a crucial component of the social safety net in the United States, yet there is limited supporting evidence on the effects of WIC on the nutritional well‐being and food security of infants and young children. Using data from the National Health and Nutrition Examination Survey, we apply recently developed partial identification methods to jointly account for unobserved counterfactual outcomes and systematic underreporting of WIC participation. Under nonparametric assumptions, we find that WIC reduces the prevalence of child food insecurity by at least 3.6 percentage points (20%).  相似文献   
94.
Using household level data from rural Kenya, this article explores whether and how farm households respond to unfavorable agricultural production environments, including any ex post adjustments in off‐farm labor supply in response to unexpected weather shocks. While controlling for a wide range of educational, demographic, and other locational factors, we examine how long‐term weather conditions and specific rainfall shocks influence a household's decision to engage in, and their earnings from, the off‐farm labor market. We find that rural households engage in off‐farm work as a long‐term strategy to deal with the effects of anticipated weather conditions on their farming operations. The analysis does not reveal major short‐term adjustments in off‐farm engagement as a result of specific, unexpected rainfall shocks; these households do however rely on remittance income and petty agricultural wage labor under these circumstances. Holding other factors constant, and conditional on participation, households in areas with a more productive local agriculture tend to earn more from off‐farm work especially in the informal/business sector than their counterparts in regions with a less productive agriculture. As expected, a vibrant local economy in the form of public investment increases the probability of off‐farm participation.  相似文献   
95.
We examine the relationship between participation in nonagricultural labor activities and farming production decisions, focusing on the use of inputs. Using longitudinal data for Vietnam from 1993 to 1998, we find that households engaged in nonagricultural labor spend significantly more on seeds, services, hired labor, and livestock inputs. This is consistent with the hypothesis that nonagricultural labor income relaxes credit constraints to farming.  相似文献   
96.
Off‐farm labour decisions of a sample of Kansas farmers are evaluated. The central question of our analysis pertains to whether 1996 US farm policy reforms may have altered the decisions to work off the farm. The effects of policy decoupling on off‐farm labour are complex: different aspects of policy changes can have opposing effects on off‐farm work decisions. Essentially, this makes this issue an empirical question. Results show that the introduction of fixed, decoupled payments in 1996 might have reduced the likelihood of off‐farm labour participation. However, the new policy environment may have increased farm households’ revealed aversion to risk, motivating a higher participation in non‐farm labour markets. The effects of 1996 policy reforms on farm income variability could have been attenuated by changes in US crop insurance programmes and by an increase in emergency assistance payments towards the end of the 1990s. The reduction in price supports may have increased the motivation for working off the farm. The net effect of the overall reforms on off‐farm work participation is not likely to have been large.  相似文献   
97.
We estimate the perceived costs of legal requirements (‘coexistence measures’) for growing genetically modified (GM) Bt maize in Germany using a choice experiment. The costs of the evaluated ex‐ante and ex‐post coexistence measures range from zero to more than €300 per measure and most are greater than the extra revenue the farmers in our survey expect from growing Bt maize or than estimates in the literature. The cost estimates for temporal separation, the highest in our evaluation, imply that the exclusion of this measure in Germany is justified. The costliest measures of the ones that are currently applied in Germany are joint and strict liability for all damages. Our results further show that neighbours do not cause a problem and opportunities for reducing costs through agreements with them exist. Finally, we find that farmers’ attitudes towards GM crops affect the probability of adoption of Bt maize. Our results imply that strict liability will deter the cultivation of Bt maize in Germany unless liability issues can be addressed through other means, for example, through neighbours agreements.  相似文献   
98.
The article examines the effect of membership in farmer groups (MFG) on adoption lag of agricultural technologies and farm performance in Burundi, the Democratic Republic of Congo and Rwanda. We use duration and stochastic production frontier models on farm household data. We find that the longer the duration of MFG, the shorter the adoption lag and much more so if combined with extension service delivery. Farmer groups function as an important mechanism for improving farm productivity through reduced technical inefficiency in input use. We discuss policy implications under which farmer groups are a useful channel to reduce adoption lag, and the means through which improved farm performance can be achieved.  相似文献   
99.
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   
100.
Aflatoxins are a common health hazard in tropical countries, especially in rural areas. New methods to reduce aflatoxin levels in food staples, as well as cheaper test methods, are being developed, but consumers’ willingness to pay (WTP) for these improvements is unknown. A survey was conducted with a representative sample of rural consumers (1,344 in total, 63% women) in all major maize‐production zones of Kenya. The survey included an experimental auction with maize products of different qualities. The results showed that many rural consumers were aware of aflatoxins, but few understood their health risks. Respondents were willing to pay a premium for maize tested for aflatoxins and labeled, but asked a high discount for maize that was visibly contaminated with moldy grain. The premium was higher for respondents with education and in regions with aflatoxicosis outbreaks. Knowledge of aflatoxins substantially reduced the overall WTP, but did not increase the WTP for tested maize. Welfare analysis indicates that mandatory testing would result in substantial benefits if the cost of testing can be lowered to below the premium.  相似文献   
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