拜科技所賜，數位電視不再是一個夢幻名詞，而是一項正在發生的事情。數位電視的出現，絕對是傳播媒介的一大革命，因為電視將不再只是電視。當電視從類比發展到全數位化之時，整個媒體生態將產生巨變，影響的範疇包括：閱聽人的收視習慣、頻道的節目策略、收視率調查方法、政府相關法令以及廣告的新樣貌等。 長久以來，收視率調查被視為是一個很重要的回饋機制，因此收視率數據牽動了電視公司、廣告主、製作單位龐大的利潤，也決定了節目播出的長短。從收視率調查方法的演進可以發現，收視率調查向來都是順應電視媒體環境下的產物。如果說電視發展的過程是自變項的話，那麼收視率調查方式就是應變項。因此電視數位化之後勢必會增加收視率調查的複雜性、困難度以及不可預測性。 本研究主要在探討收視率調查的內涵在數位電視環境下會如何重新被定義。以及為了因應電視數位化，收視率調查公司在技術上做了哪些改良與發展。而收視率在廣告主、廣告代理商、媒體購買公司的電視媒體購買決策中所扮演的角色及重要性是否依舊？又，未來在收視率調查的執行上，除了既存的收視率調查公司之外，有沒有其他的新可能。 由於台灣目前電視數位化程度還未臻成熟，收視率調查範圍也還未觸及數位電視收視那一塊，因此本研究藉由訪談無線電視台、收視率調查公司、媒體購買公司、廣告公司的專業經理人以及專家學者，勾勒出研究問題之全貌，並且有以下的發現： 一、 收視率內涵將從狹義變成廣義 二、 應發展出與各種新收視方式相對應的測量技術 三、 收視率的重要性將隨數位化發展而逐漸遞減 四、 ABR是執行收視率數據分析、處理的另一種可能機制 / Advance of science and technology has created an illusion of digital TV reality. The debut of the digital TV is absolutely a breakthrough in the mass media as it is not merely a TV anymore. When the analogue TV was advanced into a digital one, the whole media ecology transformed, affecting categories of audience watching habits, tactics of program channels, the methods of conducting TV ratings, the new phase of related laws, as well as the styles of the advertisement services. TV ratings, long been an important feedback mechanism, have resulted in affecting gigantic profits for TV companies, advertisers, and program producers, with the data offered, and hence in deciding the length of the programs. From the evolution of TV rating methods, we come to ascertain that TV rating poll has long been the direct outcome of conforming to the media environments. And, while TV development is self-variable, TV rating survey is responding variable. Consequently, the digitalization of TV system will result in the complication, difficulty, and unexpectedness of TV rating researches. This thesis focuses on exploring how the intension of TV ratings under the digital TV environment would be relocated; and to comply with the digitalization, how the poll agencies would manage to adjust; and whether the advertisement interested parties, the ad agents, media buying houses would play the same important roles in media buying policies. And furthermore, in conducting TV ratings in the future, if there are any other possibilities in addition to the existing poll agencies. As digitalization of TV system is not mature in Taiwan, the scope of poll has not extended to reach the area yet. This thesis, in which case, is outlined by means of interviewing professionals in terrestrial broadcasting companies, TV rating poll agencies, media buying houses, advertisement agencies, in addition to consulting scholars and experts. As a result, the findings fall as: 1. The intension of TV ratings will shift from narrow to broad senses. 2. Various corresponding measurement techniques should be devised. 3. The importance of TV ratings will gradually be decreasing. 4. ABR would be a possible mechanism to conduct data analysis and process.