政黨國會表現滿意度與政黨票回顧投票模型的建立

Satisfaction of Legislative Party Performances and Modeling of Retrospective Voting for Party-list Votes

綜觀臺灣的立法委員選舉制度先後於2005年改採「單一選區兩票並立制」，並於2012年改採與總統大選「同時選舉」時程之後，選民可在同一日投下「總統票」、「選區立委候選人票」與「政黨票」三張選票。為期了解在同時選舉結構之下，影響臺灣選民投票行為之關鍵因素為何，本文以2012、2016、2020與2024年總統立委大選作為分析案例，探討選舉研究文獻過往較忽視的「政黨票」，作為選舉課責研究對象；並以「回顧性投票」作為理論基礎，建構選民「政黨國會表現滿意度」對各黨政黨票投票抉擇之影響。研究發現：在控制傳統文獻模型設定的主流變項―例如「政黨偏好」、「總統施政滿意度」與「同時選舉其他兩票」之下，選民對於過去四年「政黨國會表現滿意度」之回顧性評價，均對既有政黨、新興政黨或政黨聯盟成員的政黨票抉擇具有預測力，顯示政黨票「回顧理性」與「策略理性」之存在。

Since Taiwan’s legislator electoral system sequentially adopted the newly-revised“mixed-member majoritarian system (MMM)”in 2005 and“concurrent election timing”with the presidential election in 2012, Taiwanese citizens could simultaneously vote three ballots—including“presidential vote”,“single-member district vote”and“party-list vote”—on the same polling day. To figure out the key factors influencing Taiwanese electors’voting behaviors under the structure of concurrent elections, this essay selects four general elections of Taiwan held in 2012, 2016, 2020 and 2024 as study cases and sets the“party-list vote”as our research target of electoral accountability, often being ignored by other electoral study literatures. Based on“retrospective voting theory”, this essay tries to observe the influence of“voters’satisfaction among different parties in the Legislative Yuan”on party-list votes. Evidence finds that: in addition to traditionally-focused mainstream variables of model identification such as“party preference”,“presidential approval”,“presidential vote”and“single-member district vote”, it’s noteworthy that Taiwan voters’retrospective assessments of satisfaction with legislative performances among existing parties, new parties or coalition members also have similar predictive power on their party-list vote decisions, showing that“retrospective and strategic rationality”of party-list vote does exist.