媒體立場的群聚效應分析─以台灣地區2004年總統選舉為例

Abstract

就傳統的傳播學而言，大眾媒介負有社會責任，促進社會整合、公共利益與國家民主化。但台灣近年大眾媒介中報紙與電視已經隨著政治態勢具有其一定程度的藍綠立場。政治上的藍綠立場成為意識型態時，帶著清楚藍綠色彩的媒體也成為政治動員的一環。過去探討投票意向的研究證實選民的政黨認同是影響其投票行為的重要因素。至於媒體政黨傾向對於民眾投票行為的影響為何則少人探究。本研究突破傳統傳播學的分析方法，利用階層線性分析模式（Hierarchical Linear Model），同時考慮到媒體層次與個人層次之跨層次的分析方法，回答選民使用之媒體政治立場是否對民眾在2004年總統選舉中的投票行為具有明顯的群聚效應。本研究先利用對應分析(correspondence analysis)產生可以表達媒體藍綠立場的係數，將過去只有印象的媒體藍綠色彩，給予具體數字化。結果發現，在民眾一般印象認為是泛藍、泛綠立場的媒體與研究結果頗為一致。利用跨層次分析的結果顯示民眾所閱聽的媒體確實具有群聚效應。閱聽立場越藍媒體的民眾投給連宋的機率比投給陳呂的機率高，反之亦然。比較起來，控制了個人政黨認同之後，閱聽之媒體對民眾投票意向的群聚影響效果略為降低，但仍具統計上的顯著性。這個發現對於解釋過去，閱聽人因為有了立場再選擇媒體，還是受媒體影響而選擇政黨和候選人，即「蛋生雞、雞生蛋」問題，或許不能直接有答案，但可能是一個有趣研究的開始。

In the traditions of mass communication theory, mass media is responsible for social integration, public interests and national democratization. In recent years, however, Taiwan’s mass media, including newspapers and television stations, has been developing an organism in a symbiotic relationship with conspicuous political high profile--- so-called green and blue. As green-blue political ground is considered as different political ideologies, Taiwan’s mass media has become a unit of political mobilization. Most of he previous studies have showed that political party identity is a significant predictor of voting behavior, while scant attention in the literature has been paid to the effect of mass media political ground on voting saviors. This study is a breakthrough by using Hierarchical Linear Model that allows us to examine cross-level effect, including aggregate and individual levels. This study aims to answer whether there is a significant cluster effect of mass media with different degree of political ground on voting behaviors in 2004 presidential election in Taiwan. Correspond analysis was first used to quantify mass media’s political ground, which was classified into green or blue imaged by the public in the past. The findings accord with people’s image about Taiwan mass media’s political ground. This thesis, however, unlocks the answer in the first step. Second, the results of multilevel model confirm the existence of cluster effect of media. The audiences of media with more blue ground are more likely than their counterparts to vote for Lien-Song, and vice versa. After controlling for party identity, the cluster effect slightly declines but is still statistically significant. We still have no direct answer to the question whether audience‘s political ground in mind comes first and then affects their choice of mass media or they are under the influence of mass media to choose the political parties and candidates. It is similar to the question of which came first, the chicken or the egg and is worthy to be further investigated in the future.