回扣契約設計對季節性商品在訂貨策略上之影響

Abstract

本研究著重於在季節性商品下，製造商是否可藉由提供折扣契約改變零售商的訂貨策略以解決淡季時產能過剩而旺季時產能不足的情形使製造商在一年四季的生產能保持相對穩定。當產品有季節性需求時，企業將面臨嚴重的供給與需求不一致的問題；對製造商而言，由於調整產能的成本極高，當淡季時市場需求不足甚至沒有銷量，導致製造商的產能過剩，過多的產品將會給製造商帶來存貨成本；旺季時，需求大量湧出，造成產能不足無法及時出貨，當存貨不足時，在替代品極多的市場裡消費者會直接尋求功能類似的替代品而喪失了潛在銷售；若已接受訂單而無法準時交貨則會損害商譽。本研究以Stackleberg模型討論在市場需求確定下，只有一個製造商及一個零售商的雙邊獨佔市場，針對季節性商品的銷售特性設定折扣模型及無折扣模型，並分別比較兩種契約在不同產能下製造商的最適選擇方案及零售商的對應決策。發現零售商及製造商的最適決策會跟著產能限制的不同而改變，且產能越小，製造商越有可能提供折扣契約；除此之外，若製造商可選擇產能大小，當零售商的單位存貨成本較小而製造商的單位產能成本較高時，製造商將選擇調降產能並提供折扣契約，此時雙方的利潤都較無折扣契約高，達到了雙贏的局面。

For all of the industry, inventory management is a very important issue. Managers are facing challenges about how to set an optimal inventory level to maximize the profit. For inventory strategy, there is a trade-off between high inventory level and low inventory level. Keeping inventory in low level can decrease production cost but keeping in high inventory level can satisfy all customers’ need. Therefore, to manage the inventory in an effective and efficient way is a challenged task for managers. When the demand of the product is fluctuate upon period, managers will face a serious problem which the supply will match the market demand or not. For manufacturer, the cost of adjusting capacity is very high so manufacturer does not want to adjust her capacity frequently. Then, when a period with low demand comes, manufacturer has an excessive capacity, therefore, the every unsold goods will causes inventory cost. When a period with high demand comes, the capacity of manufacturer may not enough to satisfy the market demand. In this situation, manufacturer may suffer a potential loss for unsatisfied demand. it is because that in a competitive market, there are many competitors sale similar products. If the store can not provide a product immediately, the customer may just leave and buy the product in another store. There are many products and services whose demand occurred only in a specific period and repeated all the time. For this kind of products or services we called ” seasonal product.” Because of the demand uncertainty, it is hard to find an efficient way to solve inventory problem. In this research, Here we use a Stackleberg model to solve a seasonal issue which demand is deterministic and there are only one manufacturer and one retailer. we try to find out, for manufacturer, how to solve inventory problem in an effective way which is caused by seasonal issue. Here we use discount contract to figure out. Under a discount contract, manufacturer will offer a sales discount for every unit to retailer when demand is low. We investigate the optimal solution for manufacturer and also retailer to see how the manufacturer and retailer change their optimal strategy when the capacity constrain changed.