共查询到20条相似文献,搜索用时 15 毫秒
1.
Christopher B. Barrett Shane M. Sherlund Akinwumi A. Adesina 《Agricultural Economics》2008,38(1):21-34
This article introduces a method for estimating structural labor supply models in the presence of unobservable wages and deviations of households' marginal revenue product of self‐employed labor from their shadow wage. This method is therefore robust to a wide range of assumptions about labor allocation decisions in the presence of uncertainty, market frictions, locational preferences, etc. We illustrate the method using data from rice producers in Côte d'Ivoire. These data, like previous studies, reveal significant systematic differences between shadow wages and the marginal revenue product of family farm labor. We demonstrate how one can exploit systematic deviations, in the present case related to household characteristics such as the land/labor endowment ratio, to control for both unobservable wages and prospective allocative inefficiency in labor allocation in structural household labor supply estimation. 相似文献
2.
This article explores the dynamics of smallholder technology adoption, with particular reference to a high‐yielding, low external input rice production method in Madagascar. We present a simple model of technology adoption by farm households in an environment of incomplete financial and land markets. We then use a probit model and symmetrically censored least squares estimation of a dynamic tobit model to analyze the decisions to adopt, expand, and disadopt the method. We find that seasonal liquidity constraints discourage adoption by poorer farmers. Learning effects—both from extension agents and from other farmers—exert significant influence over adoption decisions. 相似文献
3.
Benjamin Davis Paul Winters Thomas Reardon Kostas Stamoulis 《Agricultural Economics》2009,40(2):119-123
This article introduces the articles in Agricultural Economics , vol. 40 no. 2 (March 2009). First, we introduce their objectives in a brief review of existing literature on developing country trends in rural income diversification, in particular rural nonfarm employment (RNFE) and its impact on farm technology choice in crops and livestock, and thus on agricultural modernization and diversification. Then we preview the key points of the articles, which use distinctive primary datasets from Albania, Bulgaria, China, India, Mexico, Nigeria, the Philippines, Senegal, and Vietnam to document the impacts of RNFE and their implications for farm technology and farm activity. 相似文献
4.
Xiaowei Jia Ankush Khandelwal David J. Mulla Philip G. Pardey Vipin Kumar 《Agricultural Economics》2019,50(Z1):41-50
This article provides an overview of how recent advances in machine learning and the availability of data from earth observing satellites can dramatically improve our ability to automatically map croplands over long periods and over large regions. It discusses three applications in the domain of crop monitoring where machine learning (ML) approaches are beginning to show great promise. For each application, it highlights machine learning challenges, proposed approaches, and recent results. The article concludes with discussion of major challenges that need to be addressed before ML approaches will reach their full potential for this problem of great societal relevance. 相似文献
5.
Takashi Yamano 《Agricultural Economics》2007,37(2-3):141-149
Although the long-term economic impacts of the AIDS epidemic on orphans have been major concerns, few studies have investigated the impacts of orphan status into adulthood. Therefore, this article examines the education attainment and land inheritance of former orphans, who have lost at least one parent before reaching the age of 15 years, by using household surveys in Kenya. We find about a one-year lower educational attainment among former maternal orphans compared with former nonorphans among adults who started schooling before the Free Primary Education program introduced in 1974 but not among adults who started schooling after 1974. On inherited land, we find no significant difference between households headed by former orphans and nonorphans, after controlling for land owned by parents, numbers of brothers and sisters, and birth order among brothers. 相似文献
6.
Is a reduced share of agriculture in the economy an obstacle for the agricultural sector to play an important role in poverty alleviation? What is the key channel, if any, by which agriculture is benefiting the poor in Chile that would be worthwhile to promote in other countries? By answering these questions we expand the literature on poverty and composition of growth by proposing a methodology that allows to disentangle the mechanisms by which agricultural growth can be poverty reducing. We find that in Chile agriculture plays a large role in reducing poverty, and most of this effect is channeled through the labor market. 相似文献
7.
Dutch glasshouse firms are facing the introduction of a system of tradable CO2 emission quotas. This paper employs a non‐parametric method for modelling tradable CO2 emissions of Dutch glasshouse firms. The method is capable of generating shifts in CO2 emissions across the sample of firms. Moreover, changes in volumes of outputs produced and inputs used are computed. Results show that firms using a conventional heating technology will be net purchasers of CO2 emissions, whereas firms using more advanced heating technologies will sell part of their emission quota. 相似文献
8.
If future demand for maize in Latin America and the Caribbean region (LAC) is to be met from local sources, domestic production must continue to increase. Because further expansion in the area planted to maize is precluded by the limited availability of arable land, future increases in production will have to rely heavily on the spread of productivity‐enhancing hybrid technology. Until now, the diffusion of hybrid maize in LAC has been quite variable. Using data from 18 countries, we investigate factors affecting the hybrid maize diffusion rate. Our findings validate conventional profitability‐based explanations of producer adoption behavior, but they also confirm the importance of supply‐side factors, thereby providing empirical support for the life cycle theory of seed industry development. We conclude that if policy makers in LAC are to accelerate the diffusion of hybrid maize, they will have to ensure an environment in which it is not only profitable for producers to adopt improved germplasm, but also profitable for the seed industry to produce and sell high‐quality seed. 相似文献
9.
This article seeks to provide an explanation for the relationship between domestic maize price in South Africa and world maize prices in order to evaluate comovement and transmission of world prices to domestic prices in sub‐Sahara African countries. This is done by comparing nested and nonnested models that capture different forms of nonlinearity in the price spread. Adopting a Bayesian approach that allows for comparison of models using Bayes factor, we found that the relationship between South African price and world price for maize indicates the presence of nonlinearity in price transmission with three regimes that is triggered by the price spread in previous period. 相似文献
10.
David Zilberman Eunice Kim Sam Kirschner Scott Kaplan Jeanne Reeves 《Agricultural Economics》2013,44(Z1):95-102
New discoveries in life sciences and the challenge of climate change are leading to the emergence of the bioeconomy where basic methods of advanced biology are applied to produce a wide array of products while also improving environmental quality. The emergence of the bioeconomy is a continuing evolutionary process of transition from systems of mining nonrenewable resources to farming renewable ones. This transition benefits from the modern tools of molecular biology that have expanded the human capacity to breed new organisms and utilize them to increase productivity in agriculture and fisheries as well as produce a wide array of products that were extracted in the past. This transition is leading to the integration of the agricultural sector with the energy and mineral sectors. The introduction of biotechnology has already improved the productivity of medicine as well as agriculture but, in the case of agriculture, has encountered resistance and regulatory constraints. The evolution of the bioeconomy requires continuous public investment in research and innovation as well as the establishment of a regulatory framework and financial incentives and institutions that would lead to continuous private sector investment in the development and commercialization of new products. One of the biggest challenges is the development of a regulatory framework that would control possible human and environmental externalities from new biotechnology products and, at the same time, not stifle innovation. 相似文献
11.
Rich-country support programs for cotton and sugar producers are frequently claimed to be detrimental for developing-country farmers. This study investigates whether a reduction in protectionist policies for Organization for Economic Cooperation and Development cotton and sugar producers would have a measurable effect on the welfare of Indian farmers. The fact that these sectors are intensively regulated within India might suggest that any such effect will be small. However, this study shows econometrically that prices in Indian rural markets closely follow world prices, and that Indian farmers are flexible in the medium to long run in changing production according to price signals from these markets. Depending on the crop and the nature of liberalization, producer surplus increases from 4.2% to 22.3% in the long run. 相似文献
12.
Rural poverty dynamics: development policy implications 总被引:2,自引:0,他引:2
Christopher B. Barrett 《Agricultural Economics》2005,32(S1):45-60
13.
Despite improvements in production incentives, agricultural output in Africa remained sluggish through the 1990s. Low use of purchased inputs may be part of the cause of persistently low productivity in African agriculture. This article analyzes the roles of relative prices and transactions costs in explaining low use of chemical inputs among Tanzanian coffee growers. A sample selection model indicates that output prices exert great influence on input purchases and that both fixed and variable transactions costs affect input use decisions. Travel costs in input and output markets have distinct effects on input usage, implying distinct avenues for interventions to promote more intensive use of agricultural inputs. 相似文献
14.
Ayal Kimhi 《Agricultural Economics》2006,35(1):1-9
This article examines the relationship between maize productivity and plot size in Zambia. It offers a unique empirical approach. First, it focuses on maize, which is the major crop on small and medium size farms in Zambia, but also accounts for the endogenous determination of the size of the plot devoted to maize. Previous studies have used total farm size or harvested area. Second, it corrects for selectivity in maize cultivation. Third, it controls for differences in land quality and weather conditions across districts. Finally, it offers a structural interpretation of the above framework by modeling farm decisions as a sequential, two‐stage process, in which land is first allocated to the different crops based on the information set of the farmers at the time of planting, and the yield is affected by subsequent application of inputs, the quantities of which may depend on additional information that is revealed after planting. We use this recursive structure and the differences in the information sets over time to identify the model. The results show that the endogeneity of plot size is very important in this analysis. When considering plot size as an exogenous explanatory variable, we find a monotonic positive relationship between the yield of maize and plot size, indicating that economies of scale are dominant throughout the plot size distribution. However, when we correct for the endogeneity of plot size, we find that the inverse relationship dominates the economies of scale in all plots up to 3 ha, which constitute 86% of our sample. These results suggest that market imperfections should be targeted by any policy aimed at increasing maize productivity in Zambia. 相似文献
15.
Survey data are used to examine the determinants of a “social clause” in international trade negotiations. Proponents of such a clause argue that the inclusion of labor laws, environmental impacts, and other social issues in international trade negotiations would ensure fair competition, an equitable distribution of the benefits of free trade, and, in the case of labor, protect the basic rights of workers. Opponents see these arguments as a disguised form of protectionism and self‐interest based on the protection of labor‐intensive industries in developed countries. Results from a logit model indicate a decreased likelihood for the inclusion of a social clause in international trade negotiations across farm sizes. In particular the results suggest that agricultural producers with annual gross sales including government payments between US$500,000 and US$999,000, are 40% less likely to want labor laws, environmental impacts, and food safety standards to be included as part of international trade negotiations. The results also show that agricultural producers with college experience or college degrees are less likely to want these social interventions while second generation farmers and first generation farmers with a master's degree want labor laws, environmental impacts, and food safety standards to be included as part of international trade negotiations. 相似文献
16.
This article provides a theoretical framework, based on optimal control theory, to analyze farm households' land‐use intensification decisions in forest‐based shifting cultivation (slash‐and‐burn) agroecosystems. The main results from the analysis generally coincide with the “Population Pressure Hypothesis” (PPH) as an important driver of soil degradation due to the so‐called “fallow crisis” or “deprived land‐use intensification” in shifting cultivation. However, the model also shows, from a supply perspective, that such a vicious circle of lower yields and greater forest land clearing may be avoided when the production elasticity of on‐farm labor outweighs the elasticity of substitution between farm labor and soil fertility. Furthermore, using data from shifting cultivating households from Yucatán, Mexico, we calibrate the effect of changes in population density. The numerical analysis suggests that by contrast to better‐off households, when population density increases, poorer shifting cultivating households' optimal labor allocation strategy is to further extensify land use by clearing more forest in the village common property land, or ejido land. 相似文献
17.
Muhammad E. Qureshi Sumaira E. Qureshi Malcolm K. Wegener 《Agricultural Economics》2007,36(1):113-122
Sugar mills produce a range of byproducts during the process of extracting sugar from cane. Mill mud is one of the byproducts produced in significant volume. The practice of spreading mill mud onto cane fields close by the mill has been the primary means of disposing of mill mud for many years. The continued application of mill mud at high rates, without appropriate recognition of its nutrient content, the soil condition, crop nutrient requirements, slope of the land, or proximity of application sites to environmentally sensitive areas has raised a number of concerns in recent years, including overfertilization, heavy‐metal contamination, leaching, and offsite impacts from drainage to waterways. This study develops a regional mathematical programming model to determine optimal rates of mill mud application for various soil types and distances from the mill in the Mackay region in central Queensland, Australia. The optimal application rate of mill mud varies according to soil type and by distance from the mill. Lower rates of mill mud application are economically desirable at greater distances from the mill. However, when the cost of mill mud application is shared between growers and the mill operator, the optimal application rates are reduced at some locations while increasing at others. 相似文献
18.
Based on a random sample of 240 farm households in Chiang Mai province, Thailand, this study shows that—contrary to widespread belief—Karen farm households are well-integrated into markets. Average levels of market integration are 31% for gross farm output, 35% for variable inputs, 49% for food consumption, and 80% for net family income. By estimating a two-stage least squares (2SLS) regression model, this study finds that integration into output markets is positively associated with a diversification of land use away from rice monoculture, more intense contact with nearby urban centers, and a greater number of roads connecting the village to the outside world. Controlling for these factors, the distance to urban centers does not impede market integration; distant villages are equally well integrated into output markets. The study further finds that integration into output markets improves farm productivity and net per capita income. Concerns about market integration are discussed. Results have implications for Thai policy makers who have recently placed increasing emphasis on the concept of "sufficiency economy" in order to promote the well-being of rural people. 相似文献
19.
Modeling differentiated quality standards in the agri-food sector: the case of meat trade in the enlarged EU 总被引:1,自引:0,他引:1
Quality standards play an increasingly important role in international agri-food trade, and their functioning as nontariff barriers to trade is widely discussed. We argue that food quality standards imposed by importing countries are more than just border measures and can have profound effects on the market structure of the exporting industry, thereby significantly influencing the supply response. We develop a stylized oligopoly model that accounts for compliance costs (fixed and variable) and investigate alternative policy options to explore different mechanisms an importing county may use to enhance the quality of its imports. The model explicitly recognizes the coexistence of complying and noncomplying firms, which is a situation often found in low-income countries where a small modern export-oriented segment invests in meeting foreign quality standards. We use the adjustment of the Polish meat sector to the tight EU food quality standards as an empirical example. The simulations show that a subsidy scheme can promote compliance with standards and can contribute to an upgrade of the industry in the exporting country, but its marginal effectiveness is diminishing. 相似文献