政黨政治向來為研究憲政運作、民主深化的核心議題。過往的研究，多將政黨政治視為影響憲政與民主的自變項，但憲政特性以及民主轉型的過程，也可能系統性的影響政黨體系，對於政黨體系變遷的規模、機率，存在一定的關連性。基於此，本文以政黨體系變遷為依變數，從制度特性以及民主化背景來觀察政黨體系變遷的特性。核心假設有三：首先，就制度特性而言，直選總統的國家，比起議會內閣制的國家，政黨體系變遷的機率較高、規模較大；第二，以選舉時程而言，也是制度面向的因素，在直選總統的國家中，同時選舉或蜜月選舉，因為總統衣..

Party politics is an important issue to explain the constitutional work and consolidation of a democracy, and especially for newly democracies. If the party system would be affected by different types of constitutional systems and historical legacy, the party system should also be changed. We have three hypotheses: first, we suppose those countries with a directly elected president will have a higher probability for party system change. And the smaller parties are more likely out of parliament. Second, based on the coattail effect, countrie..

法國與臺灣的政府體制都屬於半總統制，法國的憲政經驗中曾出現過三次的「左右共治」，臺灣的憲政經驗中卻從未出現過「藍綠共治」，何以如此?這是本文欲探討的課題。本文藉助賽局理論作為分析工具，探討制度安排如何影響行動者間的策略互動，以致最後產生了共治與否的差異。法國與臺灣擁有不同的選舉制度和不同的國會保障機制，在兩種制度因素的交互作用下，會引導分屬不同政黨陣營的總統和國會多數產生不同的政治計算與策略互動，最終導致法國出現「左右共治」，臺灣卻沒有出現「藍綠共治」。 ..

Both France and Taiwan’s political systems are semi-presidential. However, “cohabitation” in French constitutional experience has occurred three times while Taiwan has never seen “cohabitation” until now. Finding the reason for this difference is the central question of this paper. By using the game theory as an analysis tool, the paper explores how the institutional design influences the actors’ strategic interactions, which underlies the discrepancy between France and Taiwan in “coh..