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1.
This paper determines the cropland use associated with the dietary patterns of 16 European countries and investigates sources of variation in land use between and within these countries. The analysis combines food availability data at the household level with country-specific land use data for food items. The household food availability data is obtained from a standardized and post-harmonized databank, developed in the Data Food Networking Project (DAFNE). The results show large differences between the land use of the 16 European countries, ranging from ±1500 m2 (Ireland) to ±3000 m2 (Malta) to supply an average person’s food demand. Major reasons for this divergence include disparities in total caloric food availability and in national yields. The composition of the diet is only a minor source of variation. Using food consumption data at the household level makes it also possible to look for sources of variation within countries. This paper investigates sources of variation within countries by examining the influence of education of the household head on land use associated with food consumption. The analysis shows that diets of people with only elementary education need on average 20% more land than diets of people with a higher education (2302 m2 and 1948 m2, respectively). The basis of this difference is the higher caloric availability for people with only an elementary education; the influence of differences in the composition of the diet is negligible. Variation in land use between countries is thus caused by the different agricultural productivities and caloric availabilities, and the major source of variation within countries is the caloric availability. The composition of the diet is only a minor source of variation, both between and within countries. The results implicate that highly educated people have a lower demand for land.  相似文献   

2.
We estimate a model of drug demand and supply that incorporates insurance, advertising, and competition between branded and generic drugs within and across therapeutic classes. We use data on antiulcer drugs from 1991 to 2010. Our simulations show that generics and “me-too” drugs each increased consumer welfare more than $100 million in 2010, holding insurance premiums constant. However, insurance payments in 2010 fell by nearly $1 billion due to generics and rose by over $7 billion due to me-too antiulcer drugs.  相似文献   

3.
Sequestering carbon in soils of agro-ecosystems   总被引:1,自引:0,他引:1  
Soils of the world’s agroecosystems (croplands, grazing lands, rangelands) are depleted of their soil organic carbon (SOC) pool by 25–75% depending on climate, soil type, and historic management. The magnitude of loss may be 10 to 50 tons C/ha. Soils with severe depletion of their SOC pool have low agronomic yield and low use efficiency of added input. Conversion to a restorative land use and adoption of recommended management practices, can enhance the SOC pool, improve soil quality, increase agronomic productivity, advance global food security, enhance soil resilience to adapt to extreme climatic events, and mitigate climate change by off-setting fossil fuel emissions. The technical potential of carbon (C) sequestration in soils of the agroecosystems is 1.2–3.1 billion tons C/yr. Improvement in soil quality, by increase in the SOC pool of 1 ton C/ha/yr in the root zone, can increase annual food production in developing countries by 24–32 million tons of food grains and 6–10 million tons of roots and tubers. The strategy is to create positive soil C and nutrient budgets through adoption of no-till farming with mulch, use of cover crops, integrated nutrient management including biofertilizers, water conservation, and harvesting, and improving soil structure and tilth.  相似文献   

4.
Maize is the most important food staple in Eastern and Southern Africa, with a highly seasonal production but relatively constant consumption over the year. Farmers have to store maize to bridge seasons, for food security and to protect against price fluctuations. However, the traditional storage methods do not protect grain well, resulting in large postharvest losses. Hermetically sealed metal silos kill storage pests by oxygen deprivation without pesticides. Popular in Central America, they are now being promoted in Africa, but their impact here has not yet been studied. This study used propensity score matching to evaluate the impact of metal silos on duration of maize storage, loss abatement, cost of storage, and household food security. Metal silo adopters (N = 116) were matched with non-adopting farmers from a representative sample of 1340 households covering the major maize-growing zones in Kenya. The major effect of the metal silos was an almost complete elimination of losses due to insect pests, saving farmers an average of 150–200 kg of grain, worth KSh9750 (US$130). Metal silo adopters also spent about KSh340 less on storage insecticides. Adopters were able to store their maize for 1.8–2.4 months longer, and to sell their surplus after five months at good prices, instead of having to sell right after the harvest. The period of inadequate food provision among adopters was reduced by more than one month. We conclude that metal silos are effective in reducing grain losses due to maize-storage insects, and that they have a large impact on the welfare and food security of farm households. The initial cost of metal silos is high (KSh20,000/1.8 ton) and therefore policies to increase access to credit, to reduce the cost of sheet metal, and to promote collective action can improve their uptake by smallholder farmers.  相似文献   

5.
Farm production diversity has the potential to influence the diversity of household diets, an important nutrition outcome associated with the nutrient adequacy of diets and the nutritional status of individuals. Yet, little empirical research has assessed the relationship between farm diversity and diet diversity or the plausible causal mechanisms that may operate between these two constructs. This research examines cross-sectional data from the Malawi Third Integrated Household Survey (IHS3), a nationally representative sample of farming households in Malawi, implemented from March 2010–March 2011 as part of the World Bank Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA). These data were used to determine the relationship between farm production diversity and household dietary diversity, and to identify determinants of this relationship. Two indicators of dietary diversity, a modified Household Dietary Diversity Score (HDDS), and the Food Consumption Score (FCS), were calculated along with three indicators of farm production diversity including the Simpson’s Index, a metric accounting for both species richness and evenness. In multiple regression analyses, adjusting standard errors for the complex survey design of the IHS3 and controlling for the effects of several covariates on household dietary diversity, farm production diversity was consistently positively associated with dietary diversity (P < 0.0001). The association of increased farm diversity as measured by a combined crop and livestock measure on dietary diversity was significantly greater in woman-headed households compared to those headed by men (HDDS: P = 0.008; FCS: P = 0.076). The positive association of farm diversity with dietary diversity was also greater in wealthier households (P < 0.05). Consumption of legumes, vegetables and fruits was especially strongly associated with greater farm diversity. More diverse production systems may contribute to more diverse household diets. However, this relationship is complex; it may be influenced by gender, wealth, control of household decisions, the relative market-orientation of a household’s agricultural production, and the specific nature of farm diversity.  相似文献   

6.
This research tests a multistage model of trust in business-to-business (B2B) relationships. The model contains three forms of trust, each with unique drivers and consequences for buyer–supplier relationships. An exploratory qualitative study (N = 38) and four quantitative studies (NTotal = 616) validate the distinct stages (N1 = 140, N2 = 144, N3 = 152) and provide an overall test of the model (N4 = 180), using structural equation modeling techniques. The results support the proposed modeling of the stages and highlight a positive effect of reputation on calculative trust. Conflict resolution, communication, and sympathy positively affect cognitive trust. However, shared values do not significantly drive affective trust. Interdependence also exists among the three trust forms, both directly and indirectly. That is, calculative trust does not affect investments in relationship or confidential communication, but cognitive trust influences these constructs indirectly, through the mediation of affective trust. Affective trust also leads directly to greater investments in relationship and generates additional confidential communication.  相似文献   

7.
Our ability to research dietary changes over time and their effects on health is limited by challenges in accurately measuring food consumption. In countries where dietary surveys are scarce and rarely nationally representative, household budget surveys may serve as a useful alternative for assessing food consumption. The objective of this study was to evaluate how well household acquisition data reflects the actual intake of ultra-processed foods, using data from the 2008 to 2009 Brazilian Household Budget Survey. The food acquisition module was conducted for all households selected for the survey (n = 55,970) and a subsample corresponding to 25% of the households (n = 13,569) was randomly selected for the individual food intake module, which was conducted for all individuals aged 10 years or older (n = 34,003). Ultra-processed foods were defined as formulations made by the food industry mostly or entirely from substances extracted from foods or obtained with the further processing of constituents of foods or through chemical synthesis, with little if any whole food. Examples included candies, cookies, chips, sugar-sweetened beverages, and ready-to-eat dishes. Our results showed an important agreement between the estimates of ultra-processed food consumption obtained from household acquisition data and individual intake inside-the-home data, particularly for the relative (% of total energy) consumption of these foods. Our study thus indicates that household budget surveys are quite promising for tracking population-level changes in the consumption of ultra-processed foods. The trend toward increased consumption of food away from home in other low- and middle-income countries indicates that future household budget surveys should include the collection of these data.  相似文献   

8.
Although considerable progress has been made in understanding the determinants of risk perception and in identifying the necessary components of effective food risk and benefit communication, this has not been matched with the development of efficient and appropriate communication tools. Little work has been done examining the implications of the explosion of new media and web technologies, which may offer potential for improving food risk and benefit communication. First, this study examines the views of stakeholders (n = 38) and experts (n = 33) in the food domain on the potential use of these emerging media for food risk/benefit communication. Based on in-depth interviews in six European countries (Belgium, Ireland, Italy, Latvia, Spain and The Netherlands), strengths, weaknesses, opportunities and threats (SWOT) of social media in food risk and benefit communication were identified. Second, a Strategic Orientation Round (SOR) was used to evaluate the relative importance of the SWOT components according to stakeholders (n = 10) and experts (n = 13). Results show that both stakeholders and experts confirm a future role of social media in food risk and benefit communication. Strengths as speed, accessibility and interaction make social media an interesting tool in crisis communication or issue awareness raising. Weaknesses as the lack of a filter, low trust, the risk of information overload and a communication preference for traditional media are acknowledged.  相似文献   

9.
The potential for irrigation investments in Kenya is highly dependent upon geographical, agronomic and economic factors that need to be taken into account when assessing the long-term viability and sustainability of planned projects. This study analyzed large dam-based and small-scale irrigation potential and investment needs for Kenya based on agronomic, hydrological, and economic factors. The analysis of small-scale irrigation expansion shows that the potential for investment in small-scale projects in Kenya ranges from 54,000 ha to 241,000 hectares, with an internal rate of return from 17% to 32%. For the dam-based investment analysis, under low-cost assumption, 58 dams of 73 are profitable (IRR > 0). At high cost level, the number is 52. If we raise the IRR cutoff value to 12%, 32 dams are economically feasible. We showed that there is considerable scope for the expansion of both dam-based and small-scale irrigation in Kenya, and we also provided a strategic prioritization for investments in irrigation schemes and projects.  相似文献   

10.
Food security in an important public policy issue. In 2015, approximately 1 in 8 U.S. households experienced food insecurity at some point in the year. Low-income families are at higher risk for food insecurity than other families, and these families may also face higher levels of disruption (e.g., moves, loss of income, or individuals entering or leaving the household) than other families. I use data from the Survey of Income and Program Participation to explore the relationship between food insecurity, the household’s history during the previous year, and SNAP participation. The results indicate that a number of aspects of the household’s recent experience including negative income shocks, moves, and both increases and decreases in household size increase the probability of being food insecure while SNAP participation is estimated to reduce the probability of being food insecure.  相似文献   

11.
Information is often distributed asymmetrically in exchange relationships, opening the door for opportunistic behaviors. Yet extant research has found that information asymmetry may decrease opportunism and increase performance in some contexts. Also contrary to expectations, information sharing has been found to decrease performance in some contexts. This study uses meta-analytic techniques to reconcile these contradictory findings. The results indicate that organizational setting, product type, market type, relationship duration, and construct operationalization can account for the inconsistent findings reported in extant research. Of particular interest: 1) information asymmetry is related negatively to performance in goods settings and positively to performance in services settings; 2) information asymmetry produces stronger deleterious effects in interorganizational (versus intraorganizational) settings; 3) information sharing generates stronger favorable effects in consumer (versus industrial) markets; and 4) the negative relationship between information sharing and opportunism is weaker in relationships that are 6 + years old.  相似文献   

12.
Many electricity demand estimates have been obtained based on the assumption that consumers optimize with respect to known marginal prices, but increasing empirical evidence suggests that consumers are more likely to respond to average prices. Under this assumption, this paper develops a new strategy based on Generalized Method of Moments to estimate household electricity demand. Our demand estimation approach uses publicly available expenditure data and utility-level consumption data from several major U.S. cities, complementing studies that use individual billing data which are richer yet often proprietary. We estimate the price elasticity near − 0.50, which is at the upper end (in magnitude) among the estimates from previous studies. This could have important implications for policy analysis such as those on climate policies that may affect electricity prices.  相似文献   

13.
14.
Manufacturers increasingly engage in servitization and as a result offer services in combination with their products (i.e., product-service systems, PSS). However, while servitization in theory seems to be a promising strategy, in practice, the bundling of services with product offerings does not always result in the expected performance outcomes. In this paper, we propose a framework that helps manufacturers to overcome this servitization paradox. The underlying premise of our framework is the need to give primacy to the value customers derive from PSS. The framework builds on the idea that products and services differ with regard to the value that is created by the tangible elements and the interaction moments between manufacturers and customers; this is presented in a 2 × 2 matrix. Subsequently, this paper provides guidelines for identifying PSS that are effective in terms of value creation. First, the product and service elements of the PSS should have sufficient autonomous value to be sold separately on the market. Secondly, they should come from different quadrants of the 2 × 2 matrix. Lastly, the combination of product and service elements should create synergy. Through a survey among product and service developers and an experimental auction among customers we validate our ideas.  相似文献   

15.
The aim of this paper is to investigate the demand for broadband services in Greece and to estimate the price elasticity of the demand for ADSL and ISDN services as well as the cross-price elasticity between the two services. The empirical analysis uses the 384 kbps connections since for the period examined, over 85% of the total ADSL customers in Greece are connected at this bandwidth. The empirical analysis is based on an ad-hoc specification of the demand equation, with no reference to the utility maximization problem of the representative consumer. The results of the analysis show that both demands are inelastic. In addition, cross-price elasticity for ADSL is negative, indicating that ISDN is a complement to ADSL, whereas the demand for ISDN is almost neutral to ADSL.  相似文献   

16.
A proposal to lower the bulk tank Somatic Cell Count (SCC) maximum for United States of America (US) Grade “A” milk producers was not adopted by the National Conference on Interstate Milk Shipments in 2011 or 2013. The proposal would have made the US Grade “A” limit consistent with many other international standards, including that of the European Union (EU). Some US states, however, have proactively adopted their own SCC limit to mirror the EU limit. The purpose of this study was to analyze the impacts on Wisconsin dairy producers if Wisconsin should adopt the current EU limit and compliance criterion. Analyses were done on SCC results for Wisconsin Grade “A” and Grade “B” dairy producers reported each month to the Wisconsin Department of Agriculture, Trade and Consumer Protection (WDATCP) during January 1, 2009–December 31, 2012. Results were evaluated against the current US Grade “A” and EU compliance criteria for SCC and the percentage of (producer × month) combinations in compliance was determined. If the current EU SCC compliance criterion was in place, 86.7–94.3 and 64.3–77.3% of Wisconsin Grade “A” and “Grade “B” (producer × month) combinations, respectively, would have been in compliance for the years 2009–2012. Compliance of Wisconsin Grade “A” and Grade “B” producers with the existing US SCC compliance criterion during the same period was 99.3–99.7% and 87.9–93.9% (producer × month combinations) respectively. An analysis of a subset of Wisconsin Grade “A” producers indicated that smaller-volume producers were less likely than larger-volume producers to meet the EU criterion.  相似文献   

17.
The potential global demand for biofuels and the implications of this for land use and its interaction with food agriculture is reviewed. It is expected that biofuels will form an important element of global transport energy mix (in the order of 20–30% of total requirement) over the next 40 years and beyond. Over this time, there will be a transition from so called first generation biofuels, based on commodity agricultural crops with food/feed uses, to advanced biofuels, sometimes called second and third generation biofuels, based primarily upon lignocellulosic feedstocks. It remains unclear whether these advanced biofuels, based on lignocellulosic materials, will entirely replace first generation or if second generation will be supplemental to first generation. This expansion in biofuels will be coupled to a substantial increase in alternative fuels (electricity, hydrogen, biogas and natural gas) and modal shifts. Biofuel production from agricultural commodity crops that exhibit strong sustainability criteria will remain important (e.g. sugarcane) with supportive and competitive aspects for food security.Land requirement projections estimated for a range of potential biofuel development trajectories range widely and are inherently uncertain. Under the most active scenario that delivers substantive greenhouse gas reductions in transport by 2050 (relative to 2005 levels), approximately 100 Mha of additional land is projected. In the ‘business-as-usual’ scenario, in which transport energy demand rises by 80% by 2050 from present levels, a land use requirement of 650 Mha is projected.Significant potential exists for producing biofuels that possess high productivity and sustainability profiles through continued research, development and demonstration. Policy and regulation at a global level, that focuses biofuel development on these goals in ways that are synergistic with food agriculture, will simultaneously help to decarbonise transport and maintain a diverse and financially robust agricultural (and forestry) sector.  相似文献   

18.
Increased fertilizer use will likely be crucial for raising and sustaining farm productivity in Africa, but adoption may be limited by ineffectiveness under certain conditions. This article quantifies the impacts of soil characteristics on maize response to fertilizer in Zambia using a nationally representative sample of 1453 fields, combining economic, farm management and soil analysis data. Depending on soil regimes, average maize yield response estimates range from insignificant (0) to 7 maize kg per fertilizer kg. For the majority of farmers, the estimated average value cost ratio is between 1 and 2, meaning fertilizer use would be fiscally rational, barring uncertainty and transfer costs. Since transfer costs exist and outcomes are uncertain, however, many farmers may sensibly pause before deciding whether to adopt fertilizer. This suggests shifting the emphasis of chronically low fertilizer use in Africa away from explanations of “market failure” toward greater emphasis on improving fertilizer efficacy.  相似文献   

19.
Nonlinear pricing is prevalent in industries such as health care, public utilities, and telecommunications. However, this pricing scheme introduces bias into estimating elasticities for welfare analysis or policy changes. I develop a local elasticity estimation method that uses nonlinear price schedules to isolate consumers' expenditure choices from selection and simultaneity biases. This method improves over previous approaches by using commonly-available observational data and requiring only a single general monotonicity assumption. Using claims-level data on health insurance with two nonlinearities, I am able to measure two separate elasticities, and find that elasticity declines from − 0.26 to− 0.09 by the second nonlinearity. These estimates are then used to calculate moral hazard deadweight loss. This method enables estimation of many policies with nonlinear pricing which previous tools could not address.  相似文献   

20.
Food environments are potential targets for interventions to reduce obesity prevalence, particularly in island settings that are typically dependent on food imports. This observational study aimed to characterise the availability, quality and price of foods and beverages in a nationally representative sample of grocery stores in Malta using the Nutrition Environment Measures Survey for Stores (NEMS-S) instrument, and to examine the association between area-level density of different types of food stores and the likelihood of children living in these areas being overweight or obese. Fieldwork was carried out between March and May 2014. There was a strong positive correlation between store size and NEMS-S score (p = <0.001), suggesting that smaller grocery stores generally offered a smaller range of products and fewer healthy food/beverage options than larger supermarkets. Across all stores, median prices of certain ‘healthier’ versions of foods were more expensive than their less healthy alternatives. A significant association between risk of childhood overweight, and density of confectionery stores in children’s locality of residence, was found (OR 1.19; 95% CI: 1.04, 1.37). These baseline findings highlight opportunities to improve the food environment in Malta to support more healthful eating, and may be of particular interest to public health practitioners in island settings.  相似文献   

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