製造商之季節性商品最適價格折扣與產能擴充策略

Abstract

市面上充斥著形形色色的產品，有一類產品具顯著的銷售季節循環稱為季節性商品。季節性產品隨處可見，共同點就是在某個時間裡的銷售量會特別多而形成一個周期性的波動，因此季節性商品可歸類出以下兩大特性：(1)商品需求的波動性大，(2)生命週期短，上下游經常採用一次性買斷的交易模式。 由於以上的特性，零售商面臨了訂購量的問題，若向製造商訂購過多的產品一旦需求達不到預期則會發生虧損，因此為了減少倉管的人事費用以及存貨成本，並且蒐集市場更精確的資訊，而將訂貨時點訂的離銷售旺季越近越好。如此一來，會發生製造商商供貨不及使得零售商無法及時滿足消費者的需求而產生缺貨成本的情形發生。反觀製造商，在淡季因為沒有訂單而讓產能閒置，到了旺季再生產會有當季產能不足而造成缺貨的風險，使其利潤無法達到最佳；倘若製造商在淡季就生產該數量的產品則本身要承擔倉管及存貨成本費用，由此可知上下游之間的利潤彼此是有衝突的。 因此，本文是以製造商的立場在一般決策下比較導入折扣合約設計與增加產能兩個策略在何種情況下增進利潤的表現較佳，提供在不同參數環境下最佳的選擇策略。首先利用Stackelberg的模型建構製造商與零售商的決策行為，接著建立折扣合約模型與產能擴充模型探討三者對製造商利潤的影響。 製造商在淡季提供折扣合約的目的是為了降低因存貨成本造成的利潤損失以及降低產品的單位生產成本，因為價格折扣能誘使零售商在淡季將部分貨品提前取走並且訂定更多的產品。另一個策略為製造商於銷售旺季進行產能擴充，但必須支付擴充的成本，雖然如此，製造商能避免淡季生產的存貨成本負擔也可因為擴充產能後的大量生產而享有規模經濟所帶來的利益。

A product whose demand takes place only in a specific period of a year is called “seasonal product.” Due to demand uncertainty and the short life, a retailer faces a problem of determining the timing and the quantity of orders. In order to collect more information, retailers prefer to place orders closed to the peak season so that they can avoid the holding cost and therefore minimize demand forecast error. In this case, a manufacturer cannot produce enough products in the peak season due to capacity constraint. However, if the manufacturer prepares production in advance, stocking inventory will become a burden. Therefore, the manufacturer will attempt to circumvent this problem with a more efficient method. In this research, the manufacturer provides two ways to improve this problem; one is to design a discount contract, and the other is to expand capacity in the peak season. Under a discount contract, the manufacturer will offer a sale discount for every unit of the products sold in the off-peak season to induce retailers to make an early procurement. Capacity expansion in the peak season is a direct method to satisfy demand and also create economies of scale for the manufacturer. Here, we use the concept of Stackelberg game to construct our model under which a manufacturer faces a retailer to determine the optimal production strategy of a seasonal product by comparing the above two methods.