電子商務之交易面臨於法令規範尚未完備的環境，對消費者而言，建立一套制度 型信任（institution-based trust, IBT)機制將有助於降低其知覺風險，並提昇購物意圖。 本研究係以資訊科技為基礎的制度型信任機制為分析標的，進一步探討消費者對網路 商店之信任、知覺風險與購物意圖間的影響。以Yahoo!奇摩購物網站之消費者為分析 對象，透過網路問卷取得463份回函，其中有效問卷共405份。並探用結構方程式模 式驗證本研究之假設。實證發現：⑴依據結構方程式模式之配適度分析結果，本研究 之整體理論架構符合相關配適度指標之判斷標準，因此支持本研究架構之合理性，代 表相關構念間確實呈現影響關係。其中消費者對「第三者認證標章」與「付費保障機 制」下的知覺擔保效果，會對知覺風險之產生負向影響效果；但「資訊仲介商」與 「B2C交易保障機制」則不顯著；⑵前述四類制度型信任機制均正向影響消費者對網 路商店之信任；⑶消費者對網路商店之信任與知覺風險間則呈現負向顯著影響；⑷消 費者對網路商店之信任與購物意圖間呈正向影響關係；但知覺風險與購物意圖則呈現 負相關。

The transactions from EC are faced incomplete norm environment, and it is necessary to build institution-based trust (IBT) mechanisms for online customers to decrease perceived risk or increase purchase intention. The purpose of this study is to discuss the perceived effectiveness of four IT-enabled institution-based trust (IBT) mechanisms how to affect buyers" trust and perceived risk from e-retailers. Furthermore, we discuss the relationship among customers' trust on e-retailers, perceived risk and purchase intention. The sample of this study includes 463 buyers in Yahoo! Taiwan shopping through online questionnaire, and then 405 valid questionnaires are collected. Structural equation modeling is applied to test hypothesis and analyze the data. Depending on the analysis of real evidences, this study results to four main implications: (1) According to the fit test of structural equation modeling, it is pointed out that the whole theory model of this study completes the standards of the fit test. Moreover, it evidences that this model can be supported. To sum up? the results show the indeed influential relationship among constructs. The perceived effectiveness of third-party assurance seals and payment guarantees has negative impact on perceived risk. But information intermediary and B2C transactions guarantees have no effect on perceived risk. (2) We find that the perceived effectiveness of four IBT mechanisms has positive impact on customers" trust on e-retailers. (3) Furthermore, we also find that the relationship between trust and perceived risk on e-retailers is negative. (4) Finally, we find the relationship between trust and purchase intention is positive. But the relationship between perceived risk and purchase intention is negative.