探討網路口碑片面性影響知覺助益程度

Abstract

過去的文獻探討消費者對於網路口碑的知覺助益程度有著不一致的結論。其中有些學者認為雙面口碑(即同時包含正負面的評價)的知覺助益程度比起單面口碑(只包含正面或是負面評價)還要高，此現象即為雙邊評論效應(sidedness effect)，然而也有人主張單面口碑的知覺助益程度比較好。為了探討造成結論不一致的原因，本研究從兩個角度出發，一是透過消費者在購買前對產品品質的熟悉程度，因此參考與產品品質相關的兩個特徵:產品類型(搜尋性商品以及經驗性商品)和品牌聲望(高跟低)作為調節變數。我們認為搜尋性商品的品質有辦法在購買前被消費者衡量的特性使得評論得以更加客觀且易於驗證，因此雙邊評論效應比起經驗性商品更為強烈。而品牌聲望則影響了大眾對於產品的熟悉程度與印象，由於確認偏誤(confirmation bias)使得大眾傾向於信任符合品牌印象的評論，促使雙邊評論效應在不同的品牌名譽有不一樣的表現。第二個角度是考量了消費者本身的認知需求作為調節變數，認知需求高的個體更傾向於投入較多的心力處理資訊，也因此他們能從商品評論中取得更多的資訊，進而認為涵蓋資訊多的評論有更高的知覺助益程度，因此我們認為認知需求高的個體會有更強烈的雙邊評論效應。實驗結果支持了大部分的假設，我們也將試圖在文中解釋另一部分的假設沒有得到支持的原因。

Past literature has yielded inconsistent conclusions regarding consumers' perceived benefits of online word-of-mouth (WOM). Some scholars argue that the perceived helpfulness of two-sided WOM (containing both positive and negative evaluations simultaneously) is higher than that of one-sided WOM (including only positive or negative evaluations), a phenomenon termed the "sidedness effect." However, others contend that one-sided WOM is more effective. To investigate the reasons behind these inconsistent findings, this study takes two perspectives. Firstly, it examines consumers' familiarity with product quality before purchase, considering two characteristics related to product quality as moderating variables: product type (search goods and experience goods) and brand reputation (high or low). We posit that the measurable attributes of search goods allow consumers to assess product quality before purchase, making reviews more objective and verifiable, thus enhancing the sidedness effect compared to experience goods. Brand reputation influences public familiarity and impressions of the product. Due to confirmation bias, individuals tend to trust reviews aligning with their brand impressions, leading to varied manifestations of the sidedness effect based on brand reputation. The second perspective considers consumers' cognitive needs as a moderating variable. Those with higher cognitive needs invest more effort in processing information, perceiving reviews with comprehensive information as more beneficial. Therefore, it is hypothesized that individuals with high cognitive needs exhibit a stronger sidedness effect. The experimental results support most hypotheses, with explanations for unsupported hypotheses provided in the paper.