本文從買方和賣方訊息不對稱的觀點出發，以兩期的經濟模型討論存在消費者認知落差且個別消費者對商品品質的辨識能力不同情況下，相較於完全訊息，對產品價、量以及市場上供應商、消費者的決策行為與社會福利的影響。 研究結果顯示，在產品市場有消費者認知錯誤現象存在時，產品供應商可從中牟利，整體的社會福利下降，但辨識能力高的消費者可享有正的消費者剩餘。此時，消極的揭露市場產品品質訊息的方法不能挽回產品品質，而強制品質不實產品下架銷毀的政策，亦不能有效杜絕不肖業者的欺騙行為。針對販售品質不實產品的行為，政府應對業者處以罰金，方能有效遏止業者利用消費者對產品認知不完全而從中牟利的動機。

By focusing on information asymmetry, a two-period game model was built to analyze the respective behaviors of consumers and suppliers. The impacts on social welfare were also analyzed when misperceptions of food quality were found to exist and the ability to distinguish quality differed among consumers. The analysis revealed that, when misperceptions exist, suppliers will cheat when it comes to food quality in order to make profits, social welfare will decrease, and consumers with better quality distinguishing ability will enjoy positive welfare gains. Under such circumstances, the best policy to prevent suppliers from cheating consumers is to impose fines on unlawful conduct instead of passively requiring labeling or taking items off-shelf.