不利天气影响农业生产并使订单农业中各成员在履约过程中遭遇不可控风险,针对这一问题,构建了由风险厌恶的农户与风险中性的公司组成的两级农产品供应链随机利润模型,在条件风险价值(CVaR)准则下,建立了具有风险厌恶特性农户的CVaR决策模型,比较分析了不利天气对集中式与分散式决策模式下最优决策的影响。研究发现不利天气降低了供应链绩效而农户的风险厌恶特性则加剧了双边际效应,对此,设计了一种与天气指数和农户风险厌恶度相关的改进收益共享契约。研究表明:公司可依据不利天气影响的结果来设计订单契约以激励双方成为"收益共享、风险共担"的统一体,此外,在实施该订单契约后可实现农产品供应链的完美共赢协调,这弥补了分散式决策下的效率损失并增强了供应链系统的稳健性。
Aiming at the fact that adverse weather affects agricultural production and makes supply chain members suffer uncontrollable risk during contract farming, a stochastic profit model for a two-stage agricultural supply chain consisting of a risk-averse farmer and a risk-neutral company was built. Under the CVaR criterion, a CVaR decision model was constructed for the risk-averse farmer. Then the influence of adverse weather on the optimal decisions was analyzed by comparing optimal decisions in the centralized system and decentralized system. It is found that adverse weather reduces the supply chain performance and that the risk aversion of the farmer aggravates the double marginalization. In order to solve these issues, an improved revenue sharing contract was designed based on weather index and farmer's risk aversion degree. The result shows that company can motivate both parties to share revenue and bear the risks by designing the contract according to the influence of adverse weather. Besides, the perfect win-win coordination for agricultural supply chain can be achieved after the implement of this contract, which makes up the efficiency loss in the decentralized system and enhances the steadiness of the supply chain. Finally, the result obtained in this paper can provide guidance for relevant studies and firms in practice.
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