優勢零售商市場中差異性商品價格與銷量競爭之比較

Abstract

在現今社會中，大部分消費性商品會透過通路零售商售予市場顧客，而這些零售商通常販售不同品牌的商品，甚至其中一些品牌、商品本身存在替代關係。故此商品批發商與通路零售商兩者的目標存在著一些衝突。 寡佔模式中，當選擇不同的決策變數其均衡價格、需求量會有所不同。過去關於上下游市場的研究傾向把批發商視為供應鏈中較具影響力的一方。而隨著科技進步、消費者行為等改變因素，供應鏈結構近十幾年來發生巨大變化，現今越來越多優勢零售商，如：WAL-MART, CARREFORE, COSTCO 等，其對於市場影響力已經超越批發商。 本文旨在應用賽局理論探討在優勢零售商主導的市場中，零售商與批發商應該採用價格抑或銷量為其決策變數，而不同的決策變數將如何影響上下游廠商之間的互動關係。推導結果發現無論在任何情況下，零售商採用價格或銷量作決策均不影響均衡結果；當商品互為替代品（互補品）時，批發商傾向選擇銷量（價格）為其決策變數。

Most consumer goods today are sold through independent retailers who also sell other competing brands. They normally have conflicting goals from those of the manufacturers. Equilibrium prices, quantities, and profits in oligopoly models depend on the strategic variables adopted by firms. A distinction is commonly drawn between Bertrand (price) competition, where firms compete directly on prices, and Cournot (quantity) competition, where firms compete directly on quantities. Most of the previous channel studies have approached the problem from the manufacturers’ perspective, and typically made assumptions that retailers are passive decision makers and manufacturers can induce their retailers’ decisions through various incentives, pricing schedules and cooperation. However, the retailers nowadays are often much larger than many manufacturers, such as Wal-Mart, Tesco, Carrefour, etc. also known as “dominant retailers”. The purpose of this paper is to provide a precise understanding of the price and quantity competition models when differentiated products of different manufacturers sold through a common retailer.