隨著虛擬社群的盛行，我們發現很多虛擬社群中，集購活動日益普遍。過去文獻皆沒有探討該虛擬社群對於集購之影響。虛擬社群相對於其它情境，更容易聚集社群成員的共同需求，當成員在虛擬社群中發展出凝聚力及信任，可減少認知的風險。有鑒於虛擬社群的潛力，本研究目的為探究是否有哪些因子會影響虛擬社群成員加入在社群中發起的集體購物的意圖。研究結果顯示：影響集體購物加入意圖之主要因素為對主購的信任度及成員感受到虛擬社群成員彼此間的信任程度，認知風險則沒有顯著影響；但在影響對主購的信任度之主要因素則為成員本身對虛擬社群的涉入程度，次之則是成員感受到虛擬社群成員間彼此的信任程度，再者為成員感受到的主購的專業程度。這些發現顯示社群成員間彼此有高度的互動並因而產生信任，是集購活動能夠成功的主要關鍵因素，主購是否有一定的專業程度則不是那麼重要。

With the rapid growth of virtual communities, more and more group-buying are now held within the communities. However, no study discusses the effect of virtual communities on group-buying. Comparing to other transaction modes, it is easier for consumers to aggregate their demands in virtual communities. The coherence and trust among community members, at the same time, further reduce potential risks in transactions. This study aims to understand factors that affect consumer intentions to join group-buying within the virtual communities and to develop a comprehensive framework.
The results indicate that perceived trust in group-buying initiator and perceived trust in other community members are the main factors that influence consumers’ intention to join. Their perceived risk, at the same, has no significant effect. Furthermore, consumers’ involvement in the virtual community has the most effect on their perceived trust in initiators while their perceived trust in other members and the perceived expertise of the initiator are also critical factors. The results implies that the trust among members, which is resulted from their intense interactions, is the key factor of group-buying. The expertise of initiator, meanwhile, is not the critical determinant of group-buying.

Chapter 1. Introduction 1
1.1 Research Background 1
1.2 Research Motivation and Purpose 2
Chapter 2. Literature Review 5
2.1 Online Group-Buying 5
2.1.1 Online Group-Buying Definition 5
2.1.2 Online Group-Buying Model 5
2.2 Trust 6
2.3 Virtual Community 8
2.3.1 Virtual Communities Definition 8
2.3.2 Knowledge sharing and trust in virtual community 11
2.3.3 Member’s Involvement and trust in Virtual Communities 12
2.4 Perceived Risk 13
2.4.1 Definition of Perceived Risk 13
2.4.2 Types of Perceived Risk 13
2.4.3 Perceived Risk in Group-Buying 15
2.5 Social Identity Theory 15
Chapter 3. Research Model and Hypotheses 16
3.1 Research Model 16
3.2 Research Hypotheses 18
3.3 Control Variable 21
Chapter 4. Research Methodology 22
4.1 Subject 22
4.2 Measure Development 23
Chapter 5. Data Analysis and Results 27
5.1 Descriptive Statistics 27
5.2 Validity and Reliability Analysis 28
5.2.1 Construct Validity and Reliability 28
5.2.2 Measurement Model 30
5.3 Hypotheses Testing 36
5.4 Results 38
Chapter 6. Conclusion 40
6.1 Findings and Conclusion 40
6.2 Contribution and Implication 41
6.3 Research Limitations 42
6.4 Future Research 42
References 43
Appendix A: Formal Qusetionnaire(Taiwan) 49
Appendix B: Qusetionnaire System 51

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