獨立選民的類型及其投票行爲：台灣2008年總統選舉的觀察

Abstract

本研究旨在檢閱獨立選民研究文獻的爭議、區辨台灣的獨立選民、進而探討其投票模式的差異。藉由「2005年至2008年『台灣選舉與民主化調查』四年期研究規劃(Ⅳ)：民國九十七年總統選舉面訪案」提供之資料，經由統計分析，本文初步研究發現如下：首先，有關獨立選民的文獻存在至少三項爭議，包括獨立選民的形象與類型、對獨立選民的測量與操作化，以及如何解釋獨立選民的成因。其次，在台灣的純獨立選民與有政黨偏向的獨立選民無論就人口學背景或是政治態度以及政治行爲來看，皆有顯著的差異。第三，雖然獨立選民沒有長期的政黨認同，但是短期的政黨喜好度以及對候選人的整體評價皆顯著影響其投票抉擇。此外，回溯投票因素對兩類選民卻有不同的效果，初步發現執政滿意度的評價對有政黨偏向的獨立選民會產生較強的影響力；而純獨立選民則對候選人的總體評價似乎給予相對較高的比重，政黨喜好度因素對這兩類選民的影響力並沒有顯著差別。

This study aims to examine the dispute within literature concerning independent voters, differentiate independent voters in Taiwan, and therefore explore factors affecting their vote choices. Through analysis of the data from Taiwan`s Election and Democratization Study, 2008 (TEDS2008P): Presidential Election, the preliminary findings are as follows: first, there are at least three major disputes in the literature, including the conceptualization and typology of independent voters, the measurement and operationalization of independent voters, and the explanation of why and how people become independent voters. Second, there is indeed a substantial distinction between pure independents and independent leaners in Taiwan. Third, short-term party preference and the overall evaluation of candidates are the two most significant factors affecting independents` vote choices. In addition, retrospective voting exerts different level of effect on these two independents. Specifically, while satisfaction with the incumbent plays more important role on independent leaners than on pure independents, overall evaluation of candidates seems to affect pure independents more than its counterpart. The explanatory power of party preference, however, is uniform to both kinds of voters.