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1.
Over the past century, U.S. farmers have been offered a steady stream of new agricultural technologies, and more recently, experienced climate change. Because these two events have been occurring simultaneously, identifying their separate effects is difficult, and misimputation is easy. This article explicitly examines the economics of technical change and the interaction between weather and technology as revealed in a half century of panel data on U.S. Midwest rainfed state‐average corn yields. Observed yields reflect two components: yield potential and damage to the potential caused by weather and pests. Yield potential is modeled as a stochastic production frontier where nitrogen fertilization, public corn research, and introduction and adoption of biotech corn seeds impact yield potential and excess heat impacts nitrogen productivity. The yield‐damage/damage‐control function permits biotech corn plants to abate adverse effects of weather and pest events. Results include the following: nitrogen use, public corn research, and biotech seed‐corn adoption increase yield potential; soil moisture stress reduces yield potential, and excess heat severely reduces nitrogen productivity. Biotech corn plants abate yield damage caused by soil moisture stress but not excess heat.  相似文献   

2.
The paper investigates the linkages between technological change and production risk, with an application to corn. The effects of technology on risk exposure are analyzed. We define technological progress to be risk‐increasing (risk‐decreasing) if it increases (decreases) the relative risk premium. The analysis is applied to panel data from Wisconsin research stations. Conditional moments (including mean, variance and skewness) of corn yield, grain moisture and corn profit are estimated for different sites. We investigate how the trade‐off between expected return and the risk premium varies over time and over space. The empirical results indicate that technological progress contributes to reducing the exposure to risk as well as downside risk in corn production, although this effect varies across sites. They also stress the role of the relative maturity of corn hybrids as a means of managing risk.  相似文献   

3.
In this research, we examine the effects of El Niño southern oscillation (ENSO) on market dynamics of major vegetable oil prices. We adopt a smooth transition vector error correction modelling framework to analyse the impacts of ENSO events on the vegetable oil prices and, more interestingly, to investigate the asymmetric nature of the ENSO dynamics and price responses to ENSO shocks. The results confirm self‐exciting type nonlinearities in the ENSO dynamics, and presence of the so‐called transactions cost band in the system of vegetable oil prices. These nonlinearities yield the history‐specific asymmetries in the vegetable oil price dynamics, wherein effects of ENSO shocks on the ENSO dynamics and the vegetable oil prices vary considerably between different ENSO regimes. In general, positive deviations, El Niño events, result in the vegetable oil price increase, while negative deviations, La Niña events, result in decrease in the prices. We illustrate these effects using generalised impulse‐response functions and the derived asymmetry measures.  相似文献   

4.
Agrobiodiversity can provide natural insurance to risk‐averse farmers by reducing the variance of crop yield, and to society at large by reducing the uncertainty in the provision of public‐good ecosystem services, for example, CO2 storage. We analyze the choice of agrobiodiversity by risk‐averse farmers who have access to financial insurance, and study the implications for agrienvironmental policy design when on‐farm agrobiodiversity generates a positive risk externality. While increasing environmental risk leads private farmers to increase their level of on‐farm agrobiodiversity, the level of agrobiodiversity in the laissez‐faire equilibrium remains inefficiently low. We show how either one of the two agrienvironmental policy instruments can cure this risk‐related market failure: an ex ante Pigouvian subsidy on on‐farm agrobiodiversity and an ex post payment‐by‐result for the actual provision of public environmental benefits. In the absence of regulation, welfare may increase rather than decrease with increasing environmental risk, if the agroecosystem is characterized by a high natural insurance function, low costs, and large external benefits of agrobiodiversity.  相似文献   

5.
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   

6.
We investigate how self‐protection from the adoption of Improved Maize Varieties (IMV) and off‐farm income affects risk premiums for smallholder maize producers in Uganda. To unbundle these effects, we specify the cost of risk to explicitly capture four risk components—mean, variance, skewness, and kurtosis. Using unique plot‐level panel data for Uganda, we estimate and test moments of a flexible production function based on an expanded form of the Johnson SU family distribution and proceed to simulate the degree of responsiveness of risk premiums and welfare estimates to marginal changes in the share of land under IMV and off‐farm income. Scenarios of joint adoption of IMV accompanied with low and high application of inorganic fertilizer, and the effect of off‐farm income when there is high and low supply of farm labor are examined. Results show that the use of IMV and off‐farm income substantially reduces risk premiums and the individual effect is much higher under low fertilizer application and high supply of farm labor, respectively. Thus implying that self‐protection is likely to reduce the propensity for index insurance especially if its design fails to consider the reduction in downside risk.  相似文献   

7.
Using a stochastic production frontier to model potato production in Bolivia, we quantify the costs of environmental and activity diversification (AD) in the form of efficiency losses and yield forgone. We find that efficiency decreases with the number of fields in a geographical cluster, distance between the dwelling and a particular field, discontinuity between fields, and off‐farm income. However, environmental diversification (ED) is more detrimental than AD. Using spatial analysis of field and household efficiency measures, we assess production vulnerability to climatic shocks and the potential of ED in mitigating shocks. We find important spatial clusters of low and high efficiencies at the field level suggesting that climatic shocks influence efficiency measures. Household‐level efficiency measures exhibit random spatial patterns suggesting that on average households can mitigate the adverse effects of shocks through ED.  相似文献   

8.
Households in developing countries are often highly exposed to risk and despite households’ risk strategies negative shocks often result in substantial welfare losses. Given the possibility that weather risks in particular might be further increasing, there is renewed policy attention on improving households’ risk management strategies. This article provides an overview of insights learned from recent randomized control trials on predictions coming out of the theoretical literature on households’ ex ante risk management. It reveals new puzzles and questions regarding households’ inter‐temporal decision making under risk, and draws lessons for effective policy design.  相似文献   

9.
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   

10.
Rural households in the semiarid Northern Ethiopian highlands are net buyers of food. Crop failure due to erratic and unpredictable rainfall occurs frequently and leads to food shortages and income shocks. The renting out of land may be one of the coping responses of households exposed to shocks. We developed a theoretical household model for poor landlord households capturing their contract choice response to downside production shocks. We tested econometrically whether contract choice may depend on poverty, capital constraints, production risk and random shocks. The multinomial logit model estimates show that poor households experiencing random shocks are more likely to choose fixed‐rent contracts as a distress response to shocks, suggesting that fixed‐rent contracts may be used to meet immediate needs, but at the expense of future incomes. We also found that fixed‐rent contracts are preferred when ex ante production risk is low, while sharecropping is more likely where production risk is high. Finally, we found an indication that the choice of a fixed‐rent contract as a coping response to shocks comes as a last resort after all other means of coping are exhausted.  相似文献   

11.
We evaluate yield risk reduction through weather index, area yield index and farm yield insurance contracts for wheat farms in Kazakhstan by employing data from 1980 to 2002. We use the usual mean variance (MV) approach and also a second‐degree stochastic dominance (SSD) criterion. While MV is not necessarily consistent with the expected utility (EU) theory, SSD results only in a minimum but EU‐consistent benefit from insuring. Differences in the estimation results for both approaches underline the advantage of applying both criteria to analyse the risk‐reducing potential of crop insurance. Bootstrapping results show that none of the analysed insurance schemes provides statistically significant risk reduction for every single farm. In addition, weather‐based index insurance is found to provide less risk reduction than area yield insurance based on the rayon (county) yield. Moreover, rayon yield index insurance can reduce yield risk more effectively for Kazakhstan's wheat producers than farm yield insurance with a low strike yield.  相似文献   

12.
This article examines how corn prices affect the demand for feed grains and the supply of livestock outputs. The differential approach to the theory of the multiproduct firm is employed to examine ex ante decisions about feed grain demand and livestock supply. The estimation results suggest that livestock producers have little flexibility in adjusting the demand for corn in response to an increase in corn prices. The substitutable relationship between corn and distillers’ grains contributes to alleviating pressures on feed costs in response to high corn prices. In addition, the estimation results highlight that the composition of livestock supply can be altered by changes in livestock prices. On the basis of the estimated elasticities, the decompositions of profit‐maximizing input demand are conducted to examine the effects of changes in corn prices on feed grain demand and livestock supply. The decomposition results reveal that an increase in corn prices reduces corn demand but raises the demand for distillers’ grains mainly due to the substitution effects of corn price changes. The decomposition results also show that an increase in the price of corn reduces cattle supply but raises the supply of chicken and pork due to the output relationships in supply.  相似文献   

13.
Using 4‐year panel data collected from surveying 640 farmers from leading maize producing provinces in China, this study analyses how maize farmers cope with anticipated risks from bad weather by strategically adjusting variety portfolios, with particular interest in farmers' strategies in choosing and combining new and old varieties. While diversification was commonly demonstrated to be an effective means to reduce risk in most previous studies, our empirical results indicate that, in facing anticipated risks from bad weather, Chinese maize farmers tend to use fewer new varieties and allocate more land to old varieties. The lack of knowledge about weather tolerance of new varieties might be the major reason for this practice. As new varieties often have higher yield potential relative to old varieties due to technological progress, this finding suggests that Chinese maize farmers might be trading yield potential against risk reduction from bad weather. Furthermore, this study shows that maize farmers' variety adoption is significantly related to farmers' land conditions as well as their access to credit markets and technique extensions, suggesting that a well‐designed policy intervention could offset or partially offset the anticipation of adverse weather impacts on farmers' variety choices and therefore on maize production.  相似文献   

14.
This paper contributes to the contentious topic of whether shocks to agricultural commodity prices are permanent or transitory. This is an important issue with regards to forecasting, economic modelling of agricultural prices and risk management. Past studies have not accounted for important characteristics of agricultural prices that matter when testing whether shocks to prices are permanent or transitory. These include the presence or absence of a deterministic trend, the possible break in the trend, non‐stationary volatility, and the problem of the initial deviation of commodity prices from their long‐run mean or trend. We conduct a comprehensive test that incorporates all these characteristics known to plague agricultural commodity prices. Though the conclusion is mixed, the balance is in favour of agricultural price shocks being permanent in nature. This result departs from the general view that in theory, agricultural prices should be stationary, suggesting that the controversy of whether shocks to agricultural prices are temporary or permanent is not yet over.  相似文献   

15.
In rainfed production systems throughout India, agricultural activities are dependent upon the summer monsoon, and any aberration in monsoon rainfall patterns can have severe consequences for rice production. There is considerable policy interest in designing programs to lower small‐scale farmers’ exposure to these types of risk given the regularity with which adverse monsoon events occur. This paper introduces a field experiment conducted with two risk management options in the state of Odisha: a drought‐tolerant rice cultivar; and a weather index insurance product designed to complement the performance of the cultivar. Uptake rates for the cultivar itself and for the joint product are compared across two years alongside an analysis of factors that predict uptake. Results indicate high levels of demand for both the products, albeit with a significant degree of price sensitivity. But this sensitivity is agnostic to the nature of price reductions, suggesting that public investments that lower the costs of risk management may be sufficient to encourage broad uptake, without necessarily relying upon distortionary subsidies as is so often done. Sustained demand between years one and two is primarily explained where individuals were indemnified in year one and had a large number of peers also purchasing the product.  相似文献   

16.
Intra‐annual (within crop year) price volatility and inter‐annual (between crop years) price volatility are measured for wheat, maize, rice, barley, oats and rye. A set of explanatory variables is used in a pooled regression to explain variations in these price volatilities. With low cereal stocks, supply (yield) shocks (defined here as volatilities, as for the price volatilities) mostly influence inter‐annual volatility while other influential factors are the crude oil price and exchange rate. Cereal demand and interest rate shocks combined with low stocks affect intra‐annual volatility, while other explanatory factors include exchange rate and crude oil price shocks. The derivatives market activity appears to have no significant effect on either intra‐ or inter‐annual volatility. In contrast, large cereal stocks and a well‐functioning international cereal market reduce the effects of shocks in the explanatory variables on both intra‐ and inter‐annual volatilities.  相似文献   

17.
Incentives influence behaviour while an understanding of farmer behaviour facilitates the control and prevention of infectious livestock disease. This paper lays out several perspectives on how information problems and other externalities affect biosecurity incentives. We use the principal–agent framework to examine livestock disease management in the presence of potential moral hazard and adverse selection. Moral hazard may apply to biosecurity decisions while adverse selection may apply to disease reporting. The example of compensation policies illustrates the importance of creating appropriate incentives: compensation must be sufficient to ensure early reporting but not so large as to discourage appropriate levels of biosecurity effort. Other cases of externalities are more diffuse than those modelled using principal–agent analysis, placing emphasis on third‐party effects and coordination problems. Three examples are provided. One concerns free‐riding when facing an endemic disease pool that can be managed by limiting sources and flows. Another regards coordination failure when securing against an exotic disease where farmer efforts complement and communicating actions are important. The last arises from absence of a risk market where an adverse infrastructural support externality could be managed by disease outbreak insurance.  相似文献   

18.
In this paper, we model production technology in a state‐contingent framework. We assume that all the firms use the same stochastic technology, but they may have different risk attitudes and information sets, and ex post they may operate in different production environments. Firms maximise ex ante their preference function subject to a stochastic technology constraint; in other words, they are assumed to act rationally, thereby leaving no room for either technical or allocative inefficiency. We provide a simple parametric functional form to represent the state‐contingent technology. Using simple numerical examples, we illustrate how optimal input–output choices are dramatically affected when firms have different preferences and information sets. Thus, we show that the observed disparateness of production choices among different firms can actually be attributed to the stochastic nature of the decision environment.  相似文献   

19.
This paper investigates the dynamics of agricultural price volatility based on a quantile autoregression (QAR) model. The QAR model provides a flexible representation of the distribution of price and its dynamics. The approach is applied to U.S. wheat and corn markets over the period of 1980–2017. This period is of significant interest as it covers important changes in agricultural policy and increased reliance on markets. The price analysis is conducted conditional on stocks held in the previous period. We show how increasing previous stocks shift the price distribution to the left and decreases the odds of facing price spikes (by shifting down the upper tail of the price distribution). Our analysis also examines the effects of changing public stocks on prices. For both wheat and corn, this reflects changing agricultural policy, contrasting the 1980s (when public stocks were relatively high) with the post-2005 period (when public stocks became zero). We document how higher public stock ratio during the previous period did not lower the odds of facing price spikes. Applied to the wheat and corn markets, we also uncover evidence of local dynamic instability in the upper tail of the price distribution, suggesting that price instability becomes more pronounced when previous stocks are low.  相似文献   

20.
Production risk is an inherent characteristic of agriculture and changes in production risk will affect the welfare of risk‐averse producers. Using standard concepts from the literature on uncertainty, we introduce a welfare measure which comprises total factor productivity (TFP), production risk and farmer risk preferences, and which reflects the impact on producer welfare of changes in production technology. An empirical application is carried out using data from a sample of Spanish dairy farms which shows how the positive impact of increases in TFP on welfare can be offset by increases in the risk premium (‘cost of risk’) to the point where welfare may decrease.  相似文献   

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