廠商提供給顧客高品質的產品，可以帶給顧客良好的使用經驗，進而可以使顧客成為該廠商的忠誠顧客。隨著廠商所擁有的忠誠顧客增加，會促使廠商訂定更高的價格，降低促銷的幅度。這說明了廠商若能提供給顧客高品質、高服務的產品，就能避免與對手進行價格競爭。然而，透過分析不同的產業，我們會發現與此推論不同的結果。擁有較多忠誠顧客的廠商仍可能提供比對手更低的價格，進行更頻繁地促銷。我們建立一個雙頭寡佔且已知總需求量的賽局模型，並且考慮到競爭的廠商所提供的產品可以為顧客帶來不同的學習效應下，探討市場中忠誠顧客的忠誠度會對廠商定價策略有不同的影響。從本研究中，我們發現當忠誠顧客的忠誠度較高時，提供高服務品質的廠商不用擔心陷入與對手進行價格競爭的困境；而當忠誠顧客的忠誠度偏低時，提供高服務品質的廠商必須正視對手以低價搶奪市場的行為，與對手進行價格競爭。

As we all know that a well service firm can attract more loyal consumer than its rivals. Once a firm has a group of loyalty consumers, will encourage it to set higher prices and decrease promote rate. However, this does not mean that a firm can position its product at high price despit the firm provide well service. Sometimes, well service firms still have to compete against their rivals through lowering the pirce. To organize this concept, we develope a two-period, game-theoretical, duopoly model which firms differ from their ability to transfer a price-sensitive consumer to loyal consumer. Through this model, we can know that how does the ``loyalty level" affect firms' pricing strategy.
From this research, we found that when the loyal customer loyalty is at high level, well service firm do not have to fight against its opponent through lowering its price. On the contrary, when the loyal customer loyalty is at low lever, even though a firm provides well service, it still have to lower its price to maintain the turnover.

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