资金约束的供应链中交易成本对融资及运营决策的影响研究

In our project, we are planning to study a capital constrained supply chain operated under imperfect financial markets with transaction costs, and investigate how the operational decisions of supply chain members are influenced by those transaction costs. We foucs on two types of transaction costs: 1. bankruptcy costs induced by the bankruptcy risks associated with the low demand realization, and 2. the costs associated with the principal-agent issues (the diversion of loan use by the debtor without the agreement of the creditor) in the loan transaction. When a capital constrained supply chain member borrows from a bank, the potential transaction costs will force the bank to reduce its risks by imposing a limit on the available credits and/or increasing the interest rate associated with the loan.The bank's behavor will significantly influence the profitability of the whole supply chain. Comparing with the bank loans, the inborn advantage of the trade credits is that the creditor can integrate the risk control of the loan with the operational decisions. However, it is very likely that trade credits are subject to larger transaction costs than bank credits, since after all, the bank is a professional financial institution. In this research project, we focus on the comparison of the trade credits and bank credits in the presence of transaction costs. Especially, we study under the commonly used supply contracts, how the bankruptcy costs and principal-agent costs influence the bank credits, trade credits, and supply chain efficiency. Our project can lay the foundation for the joint financial and operational decisions for the supply chain members, and help the contract design and coordination in the supply chain.

本项目主要考虑一个运营在非理想金融市场下受资金约束的供应链，研究借贷过程中的交易成本对企业决策的影响。我们侧重考虑两种交易成本：一、企业因需求不确定性带来的破产风险招致的破产成本，二、债权人和债务人在借贷中因委托代理问题（即债务人在债权人不知情的情况下将贷款部分挪作他用）而产生的成本。因交易成本的存在，银行放贷时会控制贷款额度和利息以降低自身的风险，从而影响整个供应链的利润。与银行信贷比，贸易信贷的优势是债权人可以把贷款的风险控制与运营决策集成在一起，但贸易信贷受交易成本的影响程度可能比银行信贷大，因为毕竟银行是专业金融机构。所以，在存在各种交易成本的情况下比较银行信贷和贸易信贷是本项目研究重点；特别地，我们研究在各种常见的供应链合约下，破产成本和委托代理成本对两种信贷模式及供应链效率的影响。我们希望本项目的研究能帮助供应链成员实现集成化的融资和运营决策，并为供应链合约设计及协调提供依据。

本项目考虑由一个供应商和一个零售商/制造商组成的供应链，供应商和零售商/制造商均受资金约束需要向银行借款，并招致破产风险。银行通过控制贷款利率保障自身收支平衡。供应链成员可通过签订契约改变期初和期末的现金流，从而优化利润并控制破产风险。我们的研究主要有两个方面：一、存在破产成本时的供应链契约设计。我们提出了一个三参数通用契约，将文献中多种协调契约变成了其特例。当供应链中只存在可变破产成本时，实现协调的必要条件是供应链成员合理地调整期初的资金/银行贷款量；此结论在供应商和制造商原材料价格有波动的、且制造商可控制产品零售价的情况下依然成立，但契约需设定制造商违约惩罚，以防止其单方面决定停止生产；当存在固定破产成本时，如果集中式供应链固定破产成本高于一个阈值（小于分散式供应链的固定破产成本之和）时，则设计合理的契约甚至可以给分散式供应链带来比集中式供应链更高的利润。二、信誉评级对供应链融资模式的影响。当银行和企业存在需求信息不对称时，银行会在收支平衡的基础上根据企业信誉评级决定一个资金回报率。我们证明，如果供应商信誉评级高于一个阈值，则供应商提供无息贸易信用，银行资金从供应商处注入供应链；若低于此阈值，则供应商提供较高利息的贸易信用，银行资金从零售商处注入供应链。最后，资金有限但信誉评级高的零售商可能并不愿意与评级高的供应商合作，反而会选择评级低的供应商，因为他们会提供较高的提前付款折扣。