隨著數位匯流，網路電視應運而生，改變閱聽人的收視型態。有 別於過去相關研究，本研究從產業分析的政策觀點進行，以閱聽人為 主軸探討不同媒體的競爭優劣勢。此外，跳脫過去區位研究以比較新 舊媒體的優劣為主，本研究以區位理論檢視PPStream、土豆網以及 YouTube，此三種新興媒體之競爭優劣勢。採用網路問卷調查法，回 收有效問卷1,702 份。結果發現，YouTube 在所有閱聽人滿足面向上 偏向通才；PPStream 在娛樂／情感性、節目完整性／收視流暢性資源 相關面向傾向通才，其他兩個區位面向偏向專才；土豆網在互動性區 位寬度大於PPStream，其他三個區位面向都低於兩者，故土豆網在資 源使用上較偏向專才。整體而言，雖然YouTube 在各種閱聽人資源面 向有優勢，但競爭最激烈的為PPStream 與土豆網，YouTube 與土豆 網則偏向互補。

As Internet technologies have developed, the popularity of Internet Protocol television (IPTV) has increased and the viewing behavior of the public has changed. In contrast to previous studies, we focused on the audience response to 3 new types of IPTV to analyze their competitiveness in the Taiwanese television market. Using the niche theory as a theoretical framework, we investigated the competition among 3 types of IPTV: PPStream, Tudou, and YouTube. An online survey was used to collect data for this study and 1,702 valid questionnaires were obtained. The data analysis shows that YouTube occupies the top position in terms of niche breadth, niche overlap, and competitive superiority. However, strong competition exists between PPStream and Tudou.