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1.
    
Fixed transactions costs that prohibit exchange engender bias in supply analysis due to censoring of the sample observations. The associated bias in conventional regression procedures applied to censored data and the construction of robust methods for mitigating bias have been preoccupations of applied economists since Tobin [Econometrica 26 (1958) 24]. This literature assumes that the true point of censoring in the data is zero and, when this is not the case, imparts a bias to parameter estimates of the censored regression model. We conjecture that this bias can be significant; affirm this from experiments; and suggest techniques for mitigating this bias using Bayesian procedures. The bias-mitigating procedures are based on modifications of the key step that facilitates Bayesian estimation of the censored regression model; are easy to implement; work well in both small and large samples; and lead to significantly improved inference in the censored regression model. These findings are important in light of the widespread use of the zero-censored Tobit regression and we investigate their consequences using data on milk-market participation in the Ethiopian highlands.  相似文献   

2.
    
Government subsidy to crop insurance has been advocated as a policy alternative to support growth of agricultural production and farmers' income in China since the country joined the WTO. However, cautions have been raised as the crop insurance program may impact the environment negatively. This study tries to explore farmers' behaviors with regard to agrochemical use with household data applied to a simultaneous equation system consisting of disaggregated input models. It is found that decisions on fertilizer, pesticides, and agro‐film applications do have different impacts on crop insurance participation, and are influenced by the latter in different ways. It is also implied that encouraging farmers' participation in crop insurance under current low‐premium and low‐indemnity terms does not have a significantly negative impact on the environment.  相似文献   

3.
    
Studies of fertilizer use in sub-Saharan Africa have been dominated by analyses of economic and market factors having to do with infrastructure, institutions, and incentives that prevent or foster increased fertilizer demand, largely ignoring how soil fertility status conditions farmer demand for fertilizer. We apply a switching regression model to data from 260 farm households in western Kenya in order to allow for the possibility of discontinuities in fertilizer demand based on a soil carbon content (SCC) threshold. We find that the usual factors reflecting liquidity and quasi-fixed inputs are important on high-SCC plots but not on those with poorer soils. External inputs become less effective on soils with low SCC, hence the discernible shift in behaviors across soil quality regimes. For many farmers, improved fertilizer market conditions alone may be insufficient to stimulate increased fertilizer use without complementary improvements in the biophysical conditions that affect conditional factor demand.  相似文献   

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Does access to off-farm income complement or compete with agricultural production? This article explores the effect of off-farm income on agricultural production activities, using data from the 2003 Mexico National Rural Household Survey. We first discuss the theoretical conditions under which access to off-farm income may influence production in an agricultural household model. Instrumental-variable (IV) estimation methods are then used to test whether agricultural production activities, technologies, and input use differ between households with and without access to off-farm income. We find that off-farm income has a negative effect on agricultural output and the use of family labor on the farm, but a positive impact on the demand for purchased inputs. There is also a slight efficiency gain in households with access to off-farm income. Findings offer insights into how household production evolves as rural households increasingly engage in off-farm income activities.  相似文献   

6.
    
Watershed conservation is widely recognized as a major strategy for rural development throughout the developing world. In India, the apparent success of participatory approaches to watershed development resulted in a decentralization of project planning, implementation, and management to local communities at the village scale. We explore the effectiveness of this so‐called community‐based approach in achieving sustainable soil and water conservation in four semi‐arid regions in India, and analyze what factors explain project success. We confirm the result of earlier studies that participatory approaches are more effective in establishing soil and water conservation in the short run. However, our main result is that investments in community organization fail to ensure household commitment to maintenance in the longer term. Without better returns to investment in soil and water conservation and without local institutions to coordinate investment in the long run, the sustainability of participatory watershed management is seriously threatened.  相似文献   

7.
    
Shifting cultivators manage soil not only by adjusting soil use on already‐cleared lands, as in continuous cultivation, but also by clearing forests to obtain new fertile soils. This study examines the crucial link between on‐farm soil conservation and deforestation in shifting cultivation by modeling forest clearing as an investment in soil for a private farmer. More generally, by doing so the study attempts to integrate deforestation and soil conservation models which have been separately developed in the literature. Our policy goal is to arrest tropical deforestation—as destruction of global commons—caused by land degradation in shifting cultivation while improving the well‐being of poor shifting cultivators. Our integrated approach enables joint policy analyses of deforestation and land degradation. Three welfare‐enhancing policies are considered. The first is agricultural and nonagricultural subsidies affecting farm and nonfarm income opportunities. The second is fiscal and tenure policies affecting discount rates. Our question is whether the link between forest clearing and soil fertility alters the outcomes of these two standard macroeconomic policies commonly found in the literature. The third policy (or program) is various soil conservation measures affecting soil regeneration and erosivity on already‐cleared lands. This article examines a very important question which has received little attention in previous theoretical works: can soil conservation reduce deforestation? This study confirms anti‐deforestation effects of the promotion of nonfarming activities—a common and often emphasized finding in previous works—among shifting cultivators. More importantly, it also demonstrates that improving various soil conservation measures not only discourages forest clearing among shifting cultivators but also tends to have greater effects on forest protection than promoting nonfarming activities. Contrarily, agricultural price subsidy or technological progress gives rise to the opposite outcome, and lowering the farmer's discount rate or improving tenure security encourages him/her to clear more forests just to accumulate soil.  相似文献   

8.
Using first-hand data from the 2009 Employment and Informal Sector Survey (EESIC) in the two largest cities of the Republic of Congo, Brazzaville and Pointe-Noire, we analyze the impact of education on labour market outcomes, and identify the segments where education pays off the most. Multivariate analyses of the risk of unemployment and sectoral choice indicate that young people face serious difficulties in the labour market: for most of them, their only choice is to remain unemployed or to join the informal sector. To measure the specific impact of schooling on earnings, we address issues related to sample selection and endogeneity of education in the earnings function. The results shed light on heterogeneity in the returns to schooling across the two main cities and institutional sectors. An important finding is that the informal sector does not systematically lag behind the formal sectors in terms of returns to education. We emphasize convex returns to education, meaning that the last years in secondary and tertiary schooling yield the highest returns, while those of primary education are generally lower. This convexity is also apparent in the informal sector, where education (albeit on another scale) again appears as an important determinant of earnings.  相似文献   

9.
  总被引:4,自引:0,他引:4  
Although most rural households are involved in the farm sector, the nonfarm sector has grown significantly in recent decades, and its role in rural development has become increasingly important. This article examines the effect of participation in nonfarm activities on crop expenses of farm households in Nigeria. The relationship is modeled using a nonseparable agricultural household model that suggests that participating in nonfarm activities can relax the credit constraints facing farm households and reduce risk thereby helping households improve farm production and smooth consumption over time. The results show that participation in nonfarm activities by Nigerian farmers has a positive and significant effect on crop expenses and in particular on payments for hired labor and inorganic fertilizers. Separate analysis of the six geopolitical zones in Nigeria indicates that it is in the South-South and South-East zones where nonfarm participation appears to induce more hiring of labor. The results support the hypothesis that nonfarm participation helps relax liquidity constraints but suggests how that liquidity is used is zone-specific. In general, the results also indicate that liquidity is used more to pay for inputs into staple production as opposed to cash crops.  相似文献   

10.
Why do men and women adopt agricultural technologies at different rates? Evidence from Ghana suggests that gender‐linked differences in the adoption of modern maize varieties and chemical fertilizer result from gender‐linked differences in access to complementary inputs. This finding has important policy implications, because it suggests that ensuring more widespread and equitable adoption of improved technologies may not require changes in the research system, but rather introduction of measures that ensure better access for women to complementary inputs, especially land, labor, and extension services.  相似文献   

11.
    
The double hurdle model is used to analyse the off‐farm labour decisions of small‐scale agricultural household members in the Shamva District of Zimbabwe. The approach permits the joint modelling of the decision to participate in the labour market and the decision regarding the amount of time allocated to work. Results indicate that a number of variables (notably, gender, education and assets) indeed have effects which are qualitatively and quantitatively different in terms of participation and hours worked. Overall, the empirical analysis confirms the importance of individual characteristics (such as gender and education) and household/farm characteristics (e.g. land area accessible to the household, productive assets, remittances and the agricultural terms of trade) in influencing the labour market decisions of rural household members.  相似文献   

12.
This paper analyses organic farming entry decisions using a piece-wise linear depiction of policy. Our goal is to ascertain, from the available but limited information, whether Danish and UK policy measures toward organic agriculture have affected participation. Despite considerable interest in the growth of organic farming there has been little systematic analysis of it, although it is commonly believed that enhanced income levels have played a part. Whilst analyses of organic farming policy have provided extensive reviews of instruments applied, generally speaking, the spirit of those enquiries takes as datum that organic policies have had the desired impacts. Yet such conjectures remain mostly untested. Hence, there is a need to examine systematically if there exist relationships between the introduction of organic farming policies and the growth of organic farming, and whether particular policy measures are more effective than others. Here, we take a first step in this endeavor by undertaking an econometric analysis of the relationship between 14 organic farming policy measures and participation rates in Denmark and the UK during 1989–2007. Using two response variables – the numbers of farmers converted to organic production and the total land area under organic practice – we implement a simple, Bayesian methodology and evaluate the stepwise-linear impacts of policy. Extensions for future work are discussed. Six policy measures in the two study countries were found to be significant influences on participation, five of them direct supply-side instruments. For the UK, all of the policies are annual subsidies for organic farmers once conversion was complete. For Denmark, the policies are the introduction of organic subsidies for non-dairy farms, the extension of subsidies beyond 1997 and support for the costs of marketing services.  相似文献   

13.
    
In this article we address the question of farm–nonfarm linkages at the household level in Senegal. We examine whether increasing off-farm employment opportunities for rural households—resulting from increased horticulture exports and associated agro-industrialization—has benefitted the smallholder farm sector through investment linkages. We use data from a household survey in the main horticulture export region in Senegal. We find that access to unskilled employment in the export agro-industry has contributed to the alleviation of farmers' liquidity constraints, resulting in increased smallholder agricultural production.  相似文献   

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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   

16.
    
We predict the potential demand of smallholder farmers for genetically transformed varieties of a food crop, the cooking banana of the East African highlands. Farmer demand for planting material is derived in an agricultural household model that accounts for variety traits and missing markets. The demand for candidate host varieties is predicted using a Zero‐Inflated Poisson (ZIP) regression system. The fitted model is used to illustrate the sensitivity of farmer demand for improved planting material to (a) investments in research and development, represented by the effectiveness of gene insertion and expression, and (b) other public investments in education, extension, and market infrastructure that support diffusion. By comparing the characteristics of agricultural households we demonstrate that the choice of host variety can have social consequences, favoring one rural population compared with another. Clients for transgenic banana planting material are likely to be poorer, subsistence‐oriented farmers in areas greatly affected by biotic constraints. A model of this type might be useful in assessing the investments needed to support the systematic dissemination of improved planting material. The approach can be generalized to other crop biotechnologies for smallholder farming systems, particularly in developing economies.  相似文献   

17.
    
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   

18.
    
This study measures the economic impact of the first phase of the Cocoa Livelihood Program (CLP‐I), a current World Cocoa Foundation (WCF) project, sponsored by the Bill and Melinda Gates Foundation and aimed at improving the livelihood of over 200,000 small cocoa producers in sub‐Saharan Africa via training, crop diversification, and farmer‐based organizations. Using data collected from 2,048 pre‐ and post‐CLP‐I interviews of cocoa producers in Ghana, Cote d'Ivoire, Nigeria, and Cameroon, the results show that yield enhancements attributable to CLP‐I are 32%, 34%, 50%, and 62% in Ghana, Côte d'Ivoire, Nigeria, and Cameroon, respectively. Using a total program cost of $151–$200 per beneficiary and estimated annual benefits of $109–$322 per beneficiary over 25 years, the benefit‐cost ratios are estimated to range from $18 to $62 for every dollar spent on human capital development. These results suggest the WCF should endeavor to increase the number of farmers who receive all, not some, of the components of the program. This would not only help ensure that each producer obtains as much human capital as possible from each of the training programs but increases the probability of reaching the CLP goal of doubling the income of cocoa‐growing households.  相似文献   

19.
    
Child labor continues to be a major problem in developing countries, particularly in agricultural countries. The latest ILO global report points out that nine out of every ten child laborers is involved in the agricultural sector. The focus of this article is on the rural sector in India, a country where child labor continues to be prevalent. A number of factors have been found to significantly influence the extent of child labor. This article will focus on the type of technology utilized in the agricultural sector. Technology is divided into two types: biochemical and mechanical. The empirical results indicate that biochemical technology has both positive and negative effects on child labor. However, mechanical technology is found to have a statistically significant and negative impact on child labor.  相似文献   

20.
  总被引:1,自引:0,他引:1  
Land degradation poses a serious problem for the livelihoods of rural producers. Furthermore, there is rarely enough private investment taking place to commensurate the scale of the problem. This article examines the role of tenure insecurity, resource poverty, risk and time preferences, and community‐led land conservation on differentiated patterns of household investment in land conservation in northern Ethiopia. We control for biophysical, household characteristics, market access conditions, and village level factors. Investments in soil bunds and stone terraces are specifically studied so as to capture the link between these various factors and the durability of conservation investments. We introduce the distinction between the determinants of the decision to invest and how much to invest in conservation. Regression results show that publicly led conservation programs seem to significantly stimulate private investment. A host of plot‐level variables and household perceptions of returns on conservation investments, expressed in terms of perceived improvements in land quality and increased crop yields, were found to be critical to the decision to invest and intensify soil conservation. The evidence on the significance of households' attitudes toward risk aversion suggests the important role of risk and the household's risk‐bearing capacity in the decision to intensify conservation measures. At the same time, tenure security indicators and households' resource endowments (resource poverty) had weaker effects in increasing willingness to invest and the level of investment made. The policy implications of these results point to the importance of agricultural research and extension efforts that target technologies which reduce household risk and poverty while enabling sustainable investments in conservation measures by individual households.  相似文献   

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