廠商間價格數量呈現正比合約模型設計之研究

Abstract

合約設計之型態往往因不同產業型態而有所不同。本研究主要針對採購價格與交易數量呈現正向關係的情況，如熱門商品、關鍵零組件材料因天災或其他因素造成短缺供不應求之情形或在電力批發現貨市場拍賣方式都可以發現。本研究以Stackelberg模型為基礎，建構兩階層供應鏈的賽局模型，將上游設定為先行者，提供採購價格與交易數量間關係之合約；下游為跟隨者，參考市場需求及合約後再向上游表示其願意支付之採購價格。為描述上游所提出之單位採購價格及採購數量呈現正向關係的清單(schedule)模式，本研究所提出兩個模型，分別為線性合約模型與階梯合約模型，在此兩個模型中，分別探討上游供應商以單一價格收費和區段價格收費等收費方式，了解不同收費方式所會造成之結果。最後針對這些結果做敏感度分析，了解各種參數對供應鏈各成員的利潤、決策所造成之影響。

Different transaction contract types are formed in different industries. This study focuses on a special case that the downstream entity needs to offer a higher unit acquisition price in order to obtain a higher volume of products from the upstream entity. Such phenomenon may occur in the industry where there is a strong demand in the market or the capacity constraints in the upstream. We propose a two-tier supply chain based on the Stackelberg model to analyze members’ behaviors in such supply chains. In order to formulate the positive relationship between the acquisition price and product volume, we propose two models name linear contract and step function contract. And in each model we discuss different ways of charge by the upstream entity. In our model, the leader is the upstream entity who provides the downstream entity with the contract, the relationship between the acquisition price and selling quantity, and the follower is the downstream entity who determines the acquisition price. After the downstream entity determines the acquisition price or chooses the acquisition price with respect to the quantity, the upstream observes the price and offers the corresponding quantity to the downstream entity. We conduct a sensitivity analysis to examine how each parameter influences the derived results.