Time‐varying Hedge Ratios: A Principal‐agent Approach

We use the classic agency model to derive a time‐varying optimal hedge ratio for low‐frequency time‐series data: the type of data used by crop farmers when deciding about production and about their hedging strategy. Rooted in the classic agency framework, the proposed hedge ratio reflects the context of both the crop farmer's decision and the crop farmer's contractual relationships in the marketing channel. An empirical illustration of the Dutch ware potato sector and its futures market in Amsterdam over the period 1971–2003 reveals that the time‐varying optimal hedge ratio decreased from 0.34 in 1971 to 0.24 in 2003. The hedging effectiveness, according to this ratio, is 39%. These estimates conform better with farmers’ interest in using futures contracts for hedging purposes than the much higher estimates obtained when price risk minimisation is the only objective considered.     

Poisoned,Dispossessed and Excluded: A Critique of the Neoliberal Soy Regime in Paraguay

This paper challenges the recent hailing of agricultural biotechnology as a panacea for food insecurity and rural poverty in countries of the global South. Based on an empirical investigation of the neoliberal soy regime in Paraguay, I document how the profound transformation of this country's agricultural mode of production over the past two decades, spurred by the neoliberal restructuring of agriculture and the biorevolution, has jeopardized rural livelihoods. In particular, I demonstrate how the transgenic soyization of Paraguay's agriculture has led to an increased concentration of landholdings, as well as the displacement and disempowerment of peasants and rural labourers who have been rendered surplus to the requirements of agribusiness capital. At the same time, the consolidation of this new agro‐industrial model has fostered a growing dependence on agrochemicals that compromise environmental quality and human health. Thus, I argue, a development policy based on industrial monocropping of genetically modified (GM) soy is inappropriate, unsustainable and unethical.     

Stochastic frontier analysis of productive efficiency in China's Forestry Industry

Forest resources are vital to the development of green economics. Given the booming development of China's forestry industry and its ambitious reforestation efforts in the developing world, this paper is the first to use the output distance function to synthetically consider the economic and ecological outputs of China's forestry industry, and discuss its productive efficiency with a stochastic frontier model. Control and environmental variables are incorporated to capture heterogeneity in China's forestry industry, which helps us get an unbiased estimation. The empirical results show that there was no obvious efficiency disparity among China's economic regions except Northeastern China, and the state-owned forestry structure has a significantly negative effect on productive efficiency in China's forestry industry. Moreover, provinces with poor productive performance in the forestry industry such as Inner-Mongolia, Heilongjiang, and Hebei have been identified and their individual characteristics regarding productive efficiency have also been analyzed. The findings in this paper have targeted and practical implications for the development of China's forest green economy.     

The Theory of the Farm Household: An Application to Saskatchewan

A theoretical model is presented which integrates the consumption and production components of the rural household. A theoretically determined system of expenditure equations, derived factor demand equations and an off-farm labor supply equation are estimated using primary data for Saskatchewan farm households. From the empirical results we conclude that if the wage rate can be observed or estimated, the farm household's behavior can be explained empirically in a manner consistent with received theory. Summary and Conclusions A theoretical model integrating the consumption and production sides of the farm household or enterprise is estimated empirically using primary data for Saskatchewan farm households. The farm household was assumed to maximize its utility function subject to farm production and cash flow constraints. The empirical results indicate that the theoretical model can be estimated successfully even when data are sparse. While the coefficients for the expenditure, derived demand, and off-farm labor supply equations are consistent with coefficients from similar equations estimated separately by others, the theoretically more precise integrated approach specifies the simultaneous effect of the variables across equations. From the empirical results and the theoretical considerations it is obvious that the wage rate is a key explanatory variable in the model. The wage rate links the three components of the model–final expenditures, the derived input demands and off-farm labor hours. The wage rate is one determinant of the allocation of the operator's time (although other factors such as the nature of the operation and opportunities to work off-farm dominated in this study), and both the wage rate and the allocation of the time determine the eventual income available to the rural household. In essence, then, the problem of explaining farm household behavior when the household's business enterprise function cannot be separated from its consumption activity is similar to that of traditional models based on the theory of the firm and models of consumer behavior. The only difference is that the wage rate is observable in the traditional models but needs to be estimated as a shadow price in models which seek to explain rural household behavior. As a result, research in this area must start with an explanation of the allocation of (at least) the operator's labor and a measure of the shadow wage rate. If the entire household's allocation of time between on-farm and off-farm labor and leisure is determined, it is possible to treat its consumption and production activities separately. Further research is required to extend the model to explain household labor supply to both the farm and off-farm labor markets.     

A Family of Differential Input Demand Systems with Application to Greek Agriculture

This paper develops a family of input demand systems via alternative parametrisations of Theil's differential model. Each member of this family is as flexible as any other locally flexible functional form. More importantly, selection among the competing family members is possible via simple parameter restrictions. The family of differential input demand systems is applied to the agricultural sector in Greece for the period 1961–96. Formal tests suggest that the model with the CBS-type effects dominates the alternative models. Divisia and price elasticities are calculated from the selected model and a decomposition of changes in the demand for inputs into technical change, total input volume, substitution, and residual effects is performed. The empirical results are quite reasonable. Overall, the analysis in this paper indicates that, in certain cases, the differential approach may provide an attractive alternative to the dual approach in modelling production behaviour.     

Cost of abating excess nitrogen on wheat plots in France: An assessment with multi-technology modelling

We use a multi-equation model of polluting technologies to evaluate excess nitrogen's marginal abatement cost (MAC). The MAC is estimated using the convex non-parametric quantile regression. The empirical application is conducted at the plot level for wheat production in France in 2017. Results show a median shadow price for excess nitrogen of about €21 per kilogram. If the current European Union's Nitrates Directive (which sets a 170-kg constraint on organic nitrogen per hectare) were extended to mineral nitrogen, this would allow a reduction of total excess nitrogen by 9.5%, but this would be accompanied by a 3.1% decrease in wheat revenue.     

农户参与小型农田水利设施管护行为的影响因素分析——基于对河南省方城县农户的调查

利用河南省方城县192个样本农户的调查数据,运用博弈模型逻辑和二元Logistic回归分析,分别从理论和实证上探究农户参与小型农田水利设施管护行为的影响因素。研究表明:农户拥有耕地数量、家庭劳动力短缺状况、种粮补贴占种粮投入比例、种粮收入占家庭总收入比重、政府对小型农田水利设施管护投入情况、小型农田水利设施管护对农业生产的重要程度等因素对农户参与小型农田水利设施管护行为正向影响显著,而村庄农户数量对农户参与小型农田水利设施管护行为负向影响显著。最后基于实证分析结果提出了相关政策建议。     

Evaluating the impact of agricultural extension on farms' performance in Crete: a nonneutral stochastic frontier approach

This article attempts to integrate the production‐ and the efficiency‐based approaches for evaluating the impact of extension on farms' performance. For this purpose the nonneutral production frontier model is used, and the empirical analysis refers to a sample of farms from Crete, Greece. The empirical results support the proposed formulation instead of either the production‐ or the efficiency‐based formulations as extension was found to have a statistically significant effect on closing both the technology and management gaps. Public and private extension services were found to be competitive in the production function and complementary in the technical inefficiency effect function. In addition, farms using both public and private extension services achieved a higher degree of technical efficiency than those using either public or private extension services, and farms with no extension services were found to be the least efficient.     

从城乡两个战略统筹推进看农村改革路向

[目的]"城市病"与"乡村病"既是城市与乡村各自发展过程出现问题的表现,又是城乡发展长期不平衡累积的结果。从乡村振兴与新型城镇化两个战略统筹推进的视角出发,探究农村改革的重点路向。[方法]文章通过构建乡村振兴与新型城镇化评价指标体系,运用熵值法加权计算二者各自的综合指数,并运用耦合协调模型评价了现阶段我国城乡耦合协调度。[结果]从理论分析看,我国城乡融合发展具有理论上"耦合"的可行性。实证研究表明:我国乡村振兴与新型城镇化处于"区域分异"状态、发展任务艰巨且要求分区域精准施策;目前我国城乡耦合发展整体处于较低层级,70%的地区处于"轻度失调"状态,亟待通过外力干预逆转。[结论]"治好城乡两种病"不但要靠城乡自身的"内生性"发展,又需要"外源性"动力推进。从改革路向看,要结合农村实际实施差异化改革路径。并紧扣农村发展的限制性因素,针对性地破解发展难题。存在生态及自然资源优势的后发地区,应改革产业培育方向,对于经济较发达地区,改革重点应放在调整城乡分工与利益分配上;要改革土地等自然资源使用权流转制度,为城市资本下乡打开通道,使城乡融合由"离散型"转向"连续型";坚决破除"小农经济"思维模式禁锢,改革我国农业运作模式,把提升农业生产效率作为着力点。     

Drivers of food price in China: A heterogeneous panel SVAR approach

In this paper, we examine the effects of shocks in agricultural output, production material price and production price on China's food price using panel data of 26 provinces for the period 2004 Q1–2015 Q4. Employing a heterogeneous panel structural vector autoregressive (SVAR) model, we identify the causal flows between the endogenous variables via directed acyclic graphs method. The empirical results from impulse response functions and variance decompositions suggest sizeable cross‐province variations. The main driving force of food price is the price inertia shock, rather than the agricultural output or the vertical chain of price transmission shocks. The findings support the view that price expectation is the key shifter of food price. Moreover, the shocks in the vertical chain of price transmission are only weakly linked to food price. Our findings are robust to an alternative panel SVAR model identified via Cholesky decomposition.     

区域性中心城市蔓延趋势测度与控制策略 ——以山东省临沂市为例

研究目的:提出区域性中心城市蔓延趋势测度方法和蔓延控制策略。研究方法:维度分析法与实证分析法。研究结果:(1)城市蔓延是多维度现象,要综合运用单一维度测度和综合维度测度两种方法,才能全面认识和测度城市的蔓延程度;(2)临沂市城市蔓延特征总体呈现加重趋势,城市去中心度加重,城市的土地利用混合度逐渐降低,城市通达度逐渐增强,城市开敞空间逐渐减少;(3)城市蔓延是多维度共同作用的结果,要根本改变城市蔓延趋势,需要从不同维度进行综合施策。研究结论:在区域性中心城市成为城市建设用地扩展重点调控的大背景下,有效防控城市蔓延,需要科学编制区域性中心城市发展规划,并依据相关指标的测度结果,系统实施相应的城市蔓延控制策略。     

A dynamic analysis of cost-share agri-environmental programs

The purpose of this paper is to theoretically examine the efficiency of a cost-share agri-environmental program through a farm life cycle lens. Faced with a growing environmental impact from agricultural production, the farmer must decide when and how aggressively to invest in environmental capital. The steady state of the optimal control problem reveals the trade-off between allocating farm profits to consumption versus environmental improvements. A payment from a cost-share program reduces the time to investment in environmental capital, and also permanently increases the farmer's level of investment. A lack of targeting results in inframarginal farmers being paid more than the minimum amount that is required to induce investment. The portion of both the marginal payment and the average payment that induces new investment declines as the government's share of the payment increases, and this decline decreases overall program efficiency. Despite this inefficiency, a larger payment from a cost-share program is shown to decrease the farm's environmental impact in both the short and long run.     

人口规模、经济增长、资源禀赋与虚拟土地进口

[目的]分析虚拟土地进口的主要影响因素,为我国合理利用"两个市场"和"两种资源"提供决策依据。[方法]以1992~2014年的经验数据为依据,建立VAR模型,对我国人口规模、经济增长、资源禀赋与虚拟土地进口之间的关系进行实证分析。[结果]人口规模增长、经济发展以及人均耕地锐减是我国虚拟土地进口持续增长的驱动因素,三者对虚拟土地进口增长的驱动作用持续时间较长,且人口和人均耕地面积对虚拟土地进口的贡献呈不断增强趋势,但人均GDP对虚拟土地进口的贡献呈不断下降趋势。[结论]在未来一段时间内,虽然我国人口和人均GDP将继续保持双增长,但对促进虚拟土地进口增长的贡献较小,而人均耕地面积的不断减少对虚拟土地进口增长的贡献作用大,且贡献率有不断上升的趋势,耕地资源紧缺将成为我国虚拟土地进口不断攀升的主要影响因素。在当前严峻的资源环境形势下,保障耕地资源数量和质量、优化耕地资源空间配置、合理进口非粮土地密集型农产品、大力支持农业"走出去"等虚拟土地战略措施需要积极落实执行。     

重庆市县域经济发展水平及其对比分析

县域经济是城市经济和农村经济的结合点,推动县域经济的发展对于国民经济的发展、小康社会的构建都具有战略性意义。当前,我国经济已进入新常态,经济发展的内部刺激因素与外部需求环境皆出现深刻变化,县域经济的发展也迎来了新的机遇与挑战。重庆市自"十二五"以来,县域经济取得较快发展,文章通过因子分析模型及参考联合国HDI(人文发展指数)度量方式构建的评价指标体系对重庆县域经济发展的现状进行分析,发现重庆市的县域经济发展相对比较落后,且重庆市内部各县市之间经济发展也存在较大差别,经济发展并不平衡。重庆各县市应紧抓"新常态"带来的机遇,转变经济发展方式,完善产业链条,建立有竞争力的产业集群,并在此基础上着力发展特色产业,推动县域经济的可持续发展。     

An empirical framework to study food labelling fraud: an application to the Italian extra‐virgin olive oil market

The mislabelling of agricultural and food products is one of the most common types of food fraud. Despite the frequency with which labelling fraud occurs, there is no empirical framework to study its welfare implications, the probability that it may occur, and the measures that can limit its occurrence. We present an empirical framework to study the economic consequences of food labelling fraud in a differentiated products food market. Such framework requires the availability of sales data and the use of an ‘attribute‐space' demand model. The model is applied to the Italian extra‐virgin olive oil market to simulate the occurrence of fraudulent ‘100 per cent Italian' claims. Our results indicate that potential consumer losses due to overpayments for a false claim are higher than manufacturer gains, suggesting that labelling fraud results in welfare losses and not just in welfare transfers. Simulation results indicate that the level of the current administrative fines is not likely to be effective to discourage ‘100 per cent Italian' labelling fraud. Imposing larger fines or other measures negatively affecting a firm's image could be more effective in deterring labelling fraud.     

A DYNAMIC ANALYSIS OF US EXPORT WHEAT PRICING AND MARKET SHARES

The economics of a higher loan rate to support US wheat prices is analysed. Utilising optimal control theory, a dynamic wheat trade model is developed. The basic premise underlying the model is that the United States finds itself having transient monopoly power in the wheat market. An expression for the optimal pricing policy which maximises the present value of expected profits over the indefinite future is derived. Results from both the theoretical and empirical models demonstrate that the US wheat pricing strategy depends on its costs relative to competitors' costs, the discount rate and the competitors' response function. The main policy implication of the analysis is for the dominant wheat exporting country constantly to seek to lower costs relative to competitors and to maintain a price exceeding unit cost without encouraging competitors' expansion.     

AGRICULTURAL TRADE AND MCA's: A SPATIAL EQUILIBRIUM ANALYSIS

The purpose of this paper is to demonstrate how some aspects of agrimonetary system of the Common Agricultural Policy may be analysed using spatial equilibrium diagrams, modified to include foreign exchange sectors. The model analyses the effects of monetary compensatory amounts on intra-Community trade. The results are: first, when the intervention price is below the market price, both the importing and the exporting country gain in social welfare; and second, when the intervention price is effective, only the importing country gains. In each case the cost of the MCA's exceeds these welfare gains. From a budgetary viewpoint there is a trade-off between the cost of intervention buying and the cost of the trade subsidy.     

Compensated optimal response under uncertainty in agricultural household models

This study derives the qualitative properties of a household's optimal consumption, family labour, hired labour and non-labour input choices under price and/or output risk through a Slutsky-type compensation without imposing any restriction on risk preference structure or production technology. These compensated responses provide the underpinning for welfare analysis in agricultural household models under risk. The framework for the evaluation of welfare effects of product and factor price interventions in a setting of output and price risk is developed. The paper also outlines an empirical model for estimation of the compensated demand and supply responses and for validation of the paper's analytical results.     

Neighbourhood Effects in Pesticide Use: Evidence from the Rural Philippines

This study investigates how pesticide use by neighbouring farmers affects a given farmer's pesticide use. Although it is common knowledge that pesticide use has spatial externalities, few empirical economic studies explicitly analyse this issue. Applying a spatial panel econometric model to plot‐level panel data for Bohol, Philippines, this study shows that pesticide use, especially for herbicides, is spatially correlated, although there is no statistically significant spatial correlation in unobserved shocks. This implies that farmers apply pesticides by referring to the behaviour of neighbouring farmers rather than responding directly to the intensity of their own infestation.     

基于Meta分析的农户有机肥施用行为影响因素研究

[目的]有机肥施用对实现中国农业绿色发展、缓解生态环境压力至关重要,厘清农户有机肥施用行为的影响因素可为农业绿色生产行为等相关政策的制定提供参考依据。[方法]文章通过荟萃中国农户有机肥施用行为影响因素的相关实证文献,首次运用Meta分析方法评估了已有研究结论的综合效应量并明确相关影响因素的作用方向和强度。[结果]性别、家庭人口数量、家庭年收入、是否接受过技术培训及政府补贴对农户有机肥施用行为有正向促进作用,而土壤肥力对农户施用有机肥行为的影响为负作用。[结论]性别、是否接受过技术培训及政府补贴与农户有机肥施用行为存在强相关性关系;土壤肥力为中相关性影响因素,家庭人口数量为弱相关性影响因素;年龄、农户受教育年限、耕地块数、是否饲养家禽的影响较为微弱,仅属于可忽略相关性影响因素。可忽略相关性影响因素数量较多,说明目前围绕农户有机肥施用行为影响因素的实证研究尚未溯及根本,依然存在较大的研究空间。