面對資訊不全的消費情境，消費者常依簡單的推論對遺漏資訊做出判斷，而過去的消費者推論研究大多將重點放在推論結果，卻少有探討影響消費者採用推論基礎的因素，本文即深入剖析消費者主觀產品知識對其採用推論基礎的影響，及消費者心中素樸理論如何修正此推論結果。本研究共進行兩個2 (主觀產品知識：高/低) * 2 (產品屬性在品類為差異：大/小) 實驗，及一個2 (主觀產品知識：高/低) * 2 (產品屬性在該品類為差異：大/小) * 2 (素樸理論操弄：有素樸理論/無素樸理論) 的受試者間設計實驗。結果顯示：(1)高主觀知識消費者相較於低主觀知識者會使用更多元的推論基礎推論遺漏屬性；(2) 當產品屬性在品類中差異小時，消費者偏好利用品類性基礎推論遺漏屬性，而當產品屬性在品類中差異大時，消費者偏好利用關係性基礎推論遺漏屬性；(3) 高主觀知識的消費者心中的一分錢一分貨素樸理論較容易被誘發，進而修正其對最適配戴天數的估計，反之，低主觀知識的消費者的素樸理論並不影響其對最適配戴天數的推論。 There are many missing information of product in the consumer market, and consumers always rely on inference to make a judgment on missing information. This study investigated the effect of consumers’ subjective knowledge on their inference bases and the correction effects of their naive theory on the inference results. Most previous inference research focused on the results of inference, but little research discussed the factors of people’s inference bases. The focus of the current study was how consumers’ subjective knowledge influenced the inference base that they used to make an inference. This study included three experiments. The first two experiments were 2 (Subjective Knowledge: high versus low) * 2 (attribute variation in the product category: big versus small), and the third experiment was 2 (Subjective Knowledge: high versus low) * 2 (attribute variation in the product category: big versus small) * 2 (Naive theory: yes versus no) between subject design. The results indicated that consumers with high levels of subjective knowledge used more and various inference bases than consumers with low levels of subjective knowledge. Furthermore, when the attribute variation in the product category was small, consumers tended to use category-based inference. On the other hand, when the attribute variation in the product category was big, consumers tended to use correlation-based inference. Finally, consumers with high subjective knowledge would use correlation-based inference to make the inference about the missing information, and then employ naive theory to correct the inference results, but not consumers with low subjective knowledge.