本研究基於過去學者對訊息來源與產品種類之間相關性的研究發現,以二元訊息處理模型(ELM & HSM)和勸服變數的多重角色(Multiple Roles)作為基礎,探討當消費者在不同的涉入情形,訊息來源(雜誌)與產品種類相關性的高低不同,以及訊息來源(雜誌)形象與產品(特定品牌)形象符合程度的高低不同時,訊息來源可信度將如何影響消費者的品牌態度。本研究藉由實驗設計方式進行,設計同時包含種類相關性及形象符合程度之目的在於,希望證實無形的相關性(形象符合程度)之影響會大於有形相關性(種類相關性),進而釐清訊息來源可信度在說服過程中所扮演的角色。 研究結果發現,高涉入的受測者,當訊息來源與產品種類具高度相關性且形象符合程度也高時,其品牌態度會受到訊息來源可信度的影響;當產品種類具高度相關但形象不符合時,其品牌態度則不會受到訊息來源可信度的影響,然而此結果只得到部分統計支持。同樣對高涉入的受測者而言,當訊息來源與產品種類無關但形象符合程度高時,其品牌態度仍會受到訊息來源可信度的影響;而當產品種類無關且形象不符合時,則其品牌態度不會受到訊息來源可信度的影響。而低涉入的受測者,不論訊息來源與產品種類相關與否及訊息來源與品牌形象符合程度如何,高可信度的訊息來源都會產生較為正面的品牌態度。 然而,本研究結果僅足夠證實即使當訊息來源與產品種類無關時,一旦訊息來源的形象和品牌形象相符,訊息來源可信度仍會對高涉入受測者的品牌態度產生影響,並不足以證實無形的相關性之影響會大於有形相關性之影響。未來研究可以朝此一方向努力。
Source credibility often plays a major role in the persuasion processes. In past researches, source credibility has been proved to play multiple roles under different levels of involvement and source-product category relevance, which is a tangible relevance. Based on past results, we proposed an intangible perspective – image matching between source and product – and considered this variable would be more critical than tangible one. Thus, we conducted an experiment including involvement, source credibility, category relevance and image matching between source and product to prove our prediction. In addition, we applied dual-process theories, especially the concepts of “Multiple Roles” to explain our study findings. The results revealed that, first, in high involvement condition, when source’s image matches with that of product and when source is relevant to category of product, source credibility had a greater impact on product attitudes. When both the factors are low, source credibility would not influence participants’ attitudes. However, when source’s image matches with that of product but source is irrelevant to category of product, source credibility had an impact on attitudes as well. Second, in low involvement condition, no matter whether source’s image matches with that of product or not and no matter whether source is relevant to category of product or not, low involved participants’ attitude toward product from highly credible source will always be better than that from low credible source. Finally, this study found some evidences to prove that category relevance between source and product still influenced participants’ attitudes, however, this effect was proved to be overridden by image matching between source and product.