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1.
An elicitation format prevalently applied in discrete choice experiments (DCE) is to offer each respondent a sequence of choice tasks containing more than two choice options. However, empirical evidence indicates that repeated choice tasks influence choice outcomes through order effects. The study reported in this article employs a split sample approach based on field surveys to expand the research on effects of repeated‐binary DCE elicitation formats. A single‐binary elicitation format is used as the baseline. Our results indicate that choice outcomes may vary across the single‐binary and repeated‐binary elicitation formats. The choice between the two elicitation formats may imply a trade‐off between decreased choice precision in the single‐binary and order effects that may be explained by strategic misrepresentation of preferences, cost uncertainty effects and reference effects in the repeated‐binary elicitation format.  相似文献   

2.
Following the abolition of the milk quota in 2008, farmers in Switzerland strongly increased the use of concentrate feed in milk production. Against this background, the Swiss government introduced the voluntary grassland‐based milk and meat (GMF) programme in 2014, which combines economic incentives with feeding restrictions to reduce the reliance on concentrate feed and increase the use of grass feed. We analyse the economic and ecological impacts of the GMF programme at the farm and at the sector level in the short‐ and long‐run. We use a difference‐in‐differences approach (ex‐post) and an agent‐based simulation model SWISSland (ex‐ante) to construct counterfactual states to evaluate the programme's impacts. We find that the GMF programme reduces the use of concentrate feed and increases the use of grass feed in Swiss milk production. Whereas the programme has a positive effect on economic indicators such as the farm income, we find no effect on ecological indicators such as the N surplus. Our analysis suggests that feeding restrictions on concentrate feed are not enough to achieve a reduction in the N surplus. Additional feeding restrictions on grassland are necessary. Furthermore, the GMF programme has a dampening effect on sectoral milk supply, and leads to a higher milk price.  相似文献   

3.
We review the basic principles for the evaluation of design efficiency in discrete choice modelling with a focus on efficiency of WTP estimates from the multinomial logit model. The discussion is developed under the realistic assumption that researchers can plausibly define a prior belief on the range of values for the utility coefficients. D‐, A‐, B‐, S‐ and C‐errors are compared as measures of design performance in applied studies and their rationale is discussed. An empirical example based on the generation and comparison of fifteen separate designs from a common set of assumptions illustrates the relevant considerations to the context of non‐market valuation, with particular emphasis placed on C‐efficiency. Conclusions are drawn for the practice of reporting in non‐market valuation and for future work on design research.  相似文献   

4.
The global discourse on food sovereignty suggests several mechanisms for improving food security and agricultural livelihoods, including redistributive land reform and restructuring of markets to improve food distribution and access. In Brazil, the Fome Zero (Zero Hunger) social welfare programme has created innovative links between public nutrition and food security programmes and rural development initiatives through mediated market support for the family farm sector. We report on a participatory assessment of the experience of land reform beneficiaries in seven municipalities in Mato Grosso, Brazil, who were contracted to produce food for the Programa de Aquisição de Alimentos (Food Procurement Programme, PAA) and the Programa Nacional de Alimentação Escolar (National School Feeding Programme, PNAE) under the umbrella of Fome Zero. This analysis offers insight into the opportunities and challenges related to participation in mediated ‘farm‐to‐institution’ food procurement programmes, and assesses their influence on key food sovereignty principles, including agro‐ecological transition, increased market stability and farmer autonomy.  相似文献   

5.
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   

6.
Statements of willingness to pay (WTP) have been shown to be dependent upon the framing of the hypothetical market. In this paper we investigate the effects of variations in the timing and location of choice experiment questions concerned with conservation of a UK national park, as research involving measurement of psychological well‐being suggests potential differences for the same individual dependent upon when and where preferences are elicited. We apply the choice experiment technique to the valuation of changes in upland agricultural and semi‐natural landscapes in the Peak District National Park in the UK, to investigate whether timing and location of elicitation (context) affects the value associated with changes in ecosystem services under different management regimes. Four treatments are employed – using the same sample of individuals answering the same choice scenarios – to measure WTP ex‐ante (off site), in situ (on site), and ex‐post at two different time intervals (off site). We show that our on‐site (in situ) treatment generates very different estimates of preferences than any of the off‐site treatments. That stated preferences associated with environmental goods are so context dependent may have implications for the use of stated preferences in policy analysis in terms of identifying how environmental policy is funded and the divergence in value attributed to sampling different populations.  相似文献   

7.
During the 1980s and until the mid‐1990s, Peru experienced one of the bloodiest conflicts in contemporary Latin America, initiated by the armed insurrection launched by the Partido Comunista del Perú – Sendero Luminoso (Shining Path). Most guerrilla activity, armed confrontations and civilian fatalities occurred in Andean rural districts. The intensity of violence declined following the detention of PCP‐SL General Secretary Abimael Guzmán and other leading cadres in 1992–3, which resulted in the dismantling of a substantial component of the organization's military apparatus and support networks. This paper examines how surviving PCP‐SL militants attempted to regroup and respond strategically and tactically to such a devastating setback, focusing on its dealings with the civilian population, particularly coca‐producing smallholders. Counter‐insurgency measures pursued by the Peruvian state are also analysed. The paper concludes with an assessment of the current disposition of guerrillarural populationstate relations in the main areas of conflict.  相似文献   

8.
Price risk is estimated for a representative UK arable farm using value‐at‐risk (VaR). To determine the distribution of commodity returns, two multivariate generalised autoregressive conditional heteroscedasticity (GARCH) models, with t‐distributed and normally distributed errors, and a RiskMetricsTM model are estimated. Returns show excess kurtosis and that the GARCH model with t‐distributed errors fits best. Estimates of VaR differ between models: both GARCH models perform well but the RiskMetricsTM model underestimates expected losses. UK arable farms face substantial price risk.  相似文献   

9.
The land‐use optimisation framework, NZFARM, has been promoted as a tool that can be used to assess the economic and environmental impacts of policy on regional land use. This paper outlines how methodological limitations presently restrict its capacity to provide meaningful insight into the relative value of alternative land‐use configurations. The model is calibrated using positive mathematical programming, which has been shown in the literature to result in models that yield arbitrary output outside of the calibrated baseline. There is a high likelihood that this is the case, as no validation appears to have been carried out. Significant model development will be required before NZFARM outputs can be used with any confidence to inform future policy development. We conclude with suggestions on how NZFARM and models of its kind can be further developed to improve their capacity for meaningful simulation.  相似文献   

10.
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   

11.
We model production technology in a state‐contingent framework assuming that the firms maximise ex ante their preference function subject to stochastic technology constraint; in other words, firms are assumed to act rationally. We show that rational producers who face the same stochastic technology can make significantly different production choices. Further, we develop an econometric methodology to estimate the risk‐neutral probabilities, efficiency scores and the parameters of stochastic technology when there are two states of nature and only one of which is observed. Finally, we simulate noiseless data based on our state‐contingent specification of technology. Our state‐contingent estimator recovers technology parameters and other economic quantities of interest without any error. But, when we apply conventional efficiency estimators to the simulated data, we obtain biased estimates of technical efficiency.  相似文献   

12.
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   

13.
In this paper, we examine how Mexico's 1992 counter‐reforms reinforced social hierarchies between two ‘classes’ of residents within three ejidos in an agricultural frontier in Campeche. We carried out qualitative research with 94 ejidatarios, 92 pobladores and 13 government officials. Our research shows that the reforms cemented the second‐class status of pobladores, as their access to land, natural resources such as firewood and governmental subsidies is now even more contested. Ejidal residents have responded to these tensions by invoking various conceptions of citizenship to press for different forms of justice. Ejidatarios seek to enforce their legal prerogatives by advocating a tiered citizenship, inflected with aspects of ‘market citizenship’, in which pobladores have less access to resources and voice. Pobladores seek inclusion in the ejido via a cultural model of citizenship built around a ‘civil sociality’. Despite this generalization, both groups also selectively move between and combine these citizenship frameworks to advance their claims.  相似文献   

14.
Efficient experimental designs offer the potential to reduce required sample sizes, or to reduce confidence intervals for parameters of interest, in choice experiments. Choice experiment designs have typically addressed efficiency of utility function parameter estimates. The recently developed concept of C‐efficiency recognises the salience of willingness to pay estimates rather than utility function parameters in studies that seek to put money values on attributes. C‐efficiency design benefits have been illustrated in a theoretical context, but have not been tested in applied settings. This study reports a choice experiment field application that used initial responses to update statistical designs to maximise C‐efficiency. Consistent with theoretical predictions, the revised design delivered significant reductions in the variance of willingness to pay estimates, illustrating that C‐efficient designs can indeed decrease costs of choice experiments by reducing required sample sizes.  相似文献   

15.
Palm oil production creates negative externalities, e.g. through intensive fertiliser application. Policies to limit externalities need an effective, sustainable and efficient measure We use a business simulation game in a framed field experiment in Indonesia to test ex‐ante different incentives for reducing such negative externalities. This setting allows inclusion of adequate contextual features, required for reasonable ex‐ante evaluation of policy measures. The different designs of the test incentives (either a reward or punishment) varied in their magnitude and probability of occurrence but with constant effects on expected income. Results show that participants react differently to these incentives, indicating that the design can contribute significantly to effectiveness, sustainability or efficiency. A high reward with a low probability was found to be the most effective and sustainable incentive. Moreover, for the most efficient design, a low and certain reward is indicated.  相似文献   

16.
Lucerne (Medicago sativa L.) helps to prevent soil salinisation in the Western Australian Wheatbelt by reducing recharge to saline water tables. There is broad consensus, though, that it is not sufficiently profitable to motivate producers to plant it at the intensity at which considerable off‐site benefits would be conferred. This paper employs a multiple‐phase optimal control model to explore the value of this perennial pasture for the management of herbicide‐resistant annual ryegrass (Lolium rigidum Gaud.) in a crop–pasture rotation, given the difficulty of observing this value in practice. The availability of selective herbicides for efficient weed control is found to determine whether or not it is profitable to adopt lucerne pasture under optimal management. Herbicide resistance requires producers to employ costly, non‐selective treatments for in‐crop weed control. Thus, it motivates the adoption of perennial pasture in which cost‐effective forms of control can be implemented. Moreover, this result is robust to feasible changes in the current economic environment.  相似文献   

17.
This article investigates the drivers of vertical intra‐industry trade (VIIT) in Hungarian agri‐food trade with the European Union (EU). It identifies three possible ways to measure intra‐industry trade (IIT) flows (GHM, FF, and N methods) and defines six hypotheses to test for the drivers of VIIT with three panel data models (static, dynamic, and FEVD). The results suggest that factor endowments are negatively, while economic size is positively and significantly related to VIIT. Distance and VIIT were found to be negatively related as is commonly the case in the standard gravity model. It was also found that VIIT is greater if a New Member State (NMS) is exporting agri‐food produce to an NMS, while EU accession has ambiguously influenced the share of VIIT. In general, it seems that our results are independent from model estimations and interestingly they do not differ considerably as we a priori expected. Moreover, our results seem surprisingly robust across various measurements of ITT.  相似文献   

18.
Agri‐environmental schemes (AES) have had a limited effect on European agriculture due to farmers’ reluctance to participate. Information on how farmers react when AES characteristics are modified can be an important input to the design of such policies. This article investigates farmers’ preferences for different design options in a specific AES aimed at encouraging nitrogen fixing crops in marginal dry‐land areas in Spain. We use a choice experiment survey conducted in two regions (Aragón and Andalusia). The analysis employs an error component random parameter logit model allowing for preference heterogeneity and correlation amongst the non‐status quo alternatives. Farmers show a strong preference for maintaining their current management strategies; however, significant savings in cost or increased participation can be obtained by modifying some AES attributes.  相似文献   

19.
Existing approaches to the meta‐frontier estimation consist of two stages where the estimates of the local frontier parameters obtained in the first step are used to estimate meta‐frontier parameters by means of a linear or quadratic minimisation procedure in the second. Since it was shown by Schmidt (Review of Economics and Statistics 58: 238) that the second step is equivalent to constrained maximisation of a likelihood function, we extend this idea and offer a copula‐based approach to the estimation of the parameters of both meta‐ and group frontiers in a one‐step setting. In this way, we ensure a single data‐generating mechanism for the estimated parameters, expand the set of potential meta‐frontiers and account for the fact that shocks to the individual production units may be correlated with shocks to the local technological environment as a whole. We apply our estimation methodology to a data set on the world agriculture and find that the deviations from the group frontiers are positively correlated with deviations from the meta‐frontier, which is a conclusion that is impossible to reach without accounting for stochastic dependence between the two deviation types represented by a copula.  相似文献   

20.
This paper describes how political and economic transition has affected the system of agricultural production in Khorezm, Uzbekistan in terms of economic practices and relationships. Based on recent fieldwork, the paper argues that the local agricultural economy is a hybrid economy, where production for market, quasi‐market and subsistence merge into and co‐constitute one another. In order to keep the system going, and to make up for the uncertainties in the formal context of production, the relation between new private fermer and the peasant (dehkan) households is of particular importance. This relation resembles neo‐patrimonial patron–client relations, which are both personal and informal while also being based on formal, contractual relations. The relations are asymmetric and based on the limited and unevenly distributed resources. The division of power is unequal but not fixed, due to the ongoing transition of the economic system.  相似文献   

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