最近，我們可以發現以社群互動為主的市場都由單一平台主導，而許多學者都稱這樣的現象為”贏家通吃”。另外，我們也可以觀察到在網際網路的發展當中，通常都是頂尖的網站佔據了整個市場，擁有了最多數的使用者。相反的，其他的平台就只能分到剩餘的部分。
在這篇研究當中，我們選擇了台灣最大入口網站Yahoo!奇摩，以其中的電子商務部門作為主要的研究對象，電子商務部門主要負責的為拍賣、超級商城還有購物中心等的營運，訪談對象為電子商務部門的總監蕭錦薇，另外輔以Yahoo!奇摩拍賣EC-IC全國大專院校電子商務創意競賽的演講內容，希望可以透過這個案，找到贏家通吃真正的原因。
本研究回答了兩個研究問題，第一、Yahoo!奇摩的電子商務平台是如何維持他們的領導地位? 第二、贏家通吃的現象是否有在Yahoo!奇摩上顯現? 我們發現，雖然Yahoo!在剛進入台灣的時候並非成功的，但他們透過購併策略，分別購併了當時的入口龍頭奇摩站、到訪率最高的無名小站及興奇科技，相較於自行創立新部門，購併的方式可讓他們直接獲得優秀的人才以及技術的轉移。同時，也就可以讓網站本身更加多樣化，提供網友更好的服務。
最後，我們的研究結果證明了贏家通吃的現象是有在Yahoo!奇摩的營運上顯現的；另外，Yahoo!奇摩的個案研究，也可做為國外網站及公司一個好的參考，探討是否可用同樣的方式經營運作。

Recently, we observed many networked market are served almost by a single platform, and can called that situation be winner-take-all. We could observed that the top website occupy huge market, and still be the top for long time. Conversely, the other website only shares the tiny market. This paper chooses the biggest Taiwan portal Yahoo!Kimo to be the research case. In addition, the case object is its e-commerce department, which is the Yahoo! only e-commerce department worldwide. Through this case, we could find out the truth of winner-take-all. In this research, we use in-depth interview and combine with secondary data. According to past researches and the situation of Yahoo!Kimo, we address the research question as follow: (1) How does Yahoo!Kimo develop their e-store platforms to maintain their e-commerce leading position in Taiwan. (2) Is there a winner-take-all phenomenon on Yahoo!Kimo? After generalize the data, we found that although Yahoo! first time enters Taiwan not successful. Their strategy is merge different kinds website, such as the leading portal Kimo, the most visiting blog Wretch, and Monday.Tech. They got their human resource and technology sooner, then become the top one portal in Taiwan provides variety services for users. For foreign website and companies enter a new market will be a good role model. Moreover, we prove Yahoo!Kimo is role model of winner-take-all.

Chapter 1　Introduction 1
1.1 Winner-take-all 2
1.2 research purpose 3
1.3 Chapter Structure 4
Chapter 2　Literature Review 5
2.1 Winner Takes All 5
2.1.1 Some important researches 6
2.1.2 The platform and Internet 9
2.1.3 Past researches framework 9
2.2 Natural monopoly 11
2.3 Network effects 12
2.4 Multi-homing costs 13
2.5 Differentiation 14
Chapter3　Research Method 16
3.1 Research Question 16
3.2 Research Design 16
3.3 Data Collection 17
3.3.1 Interview data 17
3.3 Data analysis 21
3.4 Limitations 22
Chapter 4　Results 23
4.1 Case background information 23
4.1.1 Yahoo! 23
4.1.2 Yahoo! Kimo 24
4.1.2.1 Acquisition process 25
4.1.2.2 The Integration Strategy 26
4.1.3 Yahoo! merged Wretch 27
4.2 Yahoo!Kimo e-store introduction 28
4.2.1 Yahoo!Kimo Organization 28
4.2.2 Yahoo! Kimo Auction 29
4.2.3 Shopping Mall 29
4.2.4 Super e-Mall 30
4.3 Five e-Boulevards 30
4.3.1 Market management 31
4.3.2 Transaction safety 32
4.3.3 Virtual community relationship 34
4.3.4 Rating index 36
4.3.5 Platform investment 37
Chapter 5　Discussion 40
Chapter 6 conclusion and suggestion 45
6.1 Conclusion 45
6.2 Future Suggestion 45
Reference 47

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