以現值觀點探討零售商採信用交易最佳存貨模式

Research on Retailer's Optimal Inventory Model under Trade Credit Taking Account of Present Value

陳富子(Fu-Tzu Chen)

指導教授 ： 林賜德

中原大學/商學院/企業管理學系/碩士(2008年)

https://doi.org/10.6840/CYCU.2008.00065

摘要

金錢的時間價值是財務管理最重要的觀念之一，目前手中擁有的一塊錢，其價值遠超過未來任何時間所獲得的一塊錢，由於企業一般必須在投資計劃初期支付現金以利計劃的進行，而大多數的投資卻都要等到投資計劃開始進行後，才能相繼獲得投資報酬的現金收益，因此投資成本的現金支出和期望報酬的現金收入往往在不同的時間點發生，必須以金錢時間價值的觀念，將其折合成現值才能作比較。且近年來國際原油及原物料價格飛漲，造成嚴重的通貨膨脹，而通貨膨脹所造成機會成本的損失，更加凸顯金錢時間價值之重要性，因此，企業管理者在規劃存貨策略時，不得不將金錢的時間價值考慮在內。

本研究之主要目的，是以現值觀點探討零售商採二階信用交易之最佳存貨補充策略，其中二階信用交易是指供應商為促進零售商的提貨意願，將給予零售商固定的延後付款之信用交易期間(M)，同理，零售商也將給予顧客端固定延後付款之信用交易期間( )的優惠機制，而根據不同之信用交易期間，可將總相關成本函數分成三種不同情況來討論。當規劃週期為無限時，亦即考慮企業永續經營的情況下，本研究依據總相關成本函數之特性，推導出當滿足特定條件時，總相關成本函數為一凸函數，並可求出最佳訂購週期時間之解，但結果之算式較為複雜，必須以數值方法求解。此外，當總相關成本函數無法確定是否為凸函數時，本研究仍可依據不同之情況，求出最佳訂購週期時間，結果將大為簡化，並可利用公式計算最佳訂購量及總相關成本之最佳淨現值。最後，本文舉出不同情況之數值範例，說明如何計算最佳訂購週期時間、最佳訂購量及總相關成本之最佳淨現值。

關鍵字

最佳訂購週期時間 ； 信用交易 ； 現值 ； 總相關成本函數

並列摘要

The time value of money is one of the most important concepts in financial management. A dollar received today is worth more than a dollar received in any future time from now. A firm generally pays out costs at the beginning of an investment planning horizon immediately, but receives revenues continuously during an investment project or receives revenues at the end of an investment planning horizon. In order to compare the revenues and costs, financial managers must use the concept of the time value of money to bring the revenues and costs of an investment back to the present. Without recognizing the existence of the time value of money, it is impossible to evaluate and compare an investment project with revenues and costs occurring in different periods. So, the main purpose of this paper is to discuss retailer’s optimal inventory model under trade credit taking account of present value. For two levels of trade credit, the supplier will offer the retailer a delay period (M) to simulate his retailer demand, and the retailer will also adopt the trade credit policy ( ) to simulate his customer demand. When the cycles of an investment planning horizon is infinite, the function of the total relevant cost is discussed under three different situations. Under certain conditions, the function of the total relevant cost is convex, and a theorem is developed to determine the optimal ordering policies for the retailer. If we can not prove the function of the total relevant cost is convex or not, we can still develop a theorem to determine the optimal ordering policies for the retailer. Finally, some numerical examples are given to illustrate the theorem obtained in this paper.

並列關鍵字

the function of the total relevant cost ； trade credit ； present value ； optimal cycle time

參考文獻

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