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..

選舉制度影響政黨體系，是廣為人知的因果推論。依此邏輯，若以政黨體系為因，以選舉制度的變化為果，即產生內生性的選制變遷理論。然而，某些研究者仍認為選制變革起於和政黨體系無關的外生因素。本文主張，選制變遷是否受到政黨體系的影響，取決於選制的種類。第一，有利大黨的多數決選制如果始終未出現一黨過半，則國會屬於多黨制，有可能因為小黨組成多數聯盟而改採比例性選制。尤其當現狀為並立式單一選區兩票制時，可能因為小黨的議席多來自政黨名單，而比代表區域主義的多數決選制更容易導致..

It is well known that electoral system shapes party system. By this logic, an endogenous explanation for changes in electoral systems should treat party system as the cause and changes as the consequence, in sharp contrast with theories attributing changes to exogenous factors that are irrelevant to party system. This paper argues that whether changes in electoral system are caused by party system depend on the type of the electoral system. First, if a majority party never emerges from a majoritarian electoral system, minor p..

傳統的研究智慧中，總統制和兩黨制的配套被認為是一個民主國家較容易運作的組合。主要的理由是兩黨制較不可能出現意識形態的極化，以及因為兩個政黨需要贏得中間位置的選票，其可以促成政黨之間較溫和及向心的競爭，因而有助於總統制的運作。然而，近年來，一些兩黨總統制國家發生嚴重的憲政危機，甚至促成民主衰退。為何這些兩黨總統制國家會走上民主衰退的道路，是本文所要探索的研究問題。首先，本文透過對於拉丁美洲兩黨總統制國家的個案分析發現，憲政結構的因素如總統和國會的權力抗衡會影響..

Past research argues that presidentialism and two-party systems are workable combinations that can facilitate democratic stability. The causal mechanisms are that ideological polarization is less possible to appear in a two-party system, that two parties needing to win votes from the center encourages moderation, and that the absence of the extremist parties and the centripetal nature of party competition favor democratic stability. However, in recent years, some presidential countries with a two-party system in Latin America..

本文檢視全世界民主國家在不同總統與國會選制的搭配組合下，政黨體系有何不同。本文發現，就國會選制而言，國會選舉採比例代表制的國家， 其國會有效政黨數在整體上明顯多於國會選舉採單一選區相對多數制的國家;而不論是國會選舉採比例代表制或是採單一選區相對多數制的國家，有總統直選制度之國家的國會有效政黨數，明顯少於無總統直選制度的國家。 進一步言，在國會選舉採比例代表制的國家中，若總統選舉採相對多數制，其國會有效政黨數會少於總統選舉採兩輪決選制的國家;不過，在國會選舉採..

This study comprehensively observes the party system under different collocations of presidential and parliamentary electoral system in democracies all over the world. Regarding parliamentary electoral system, it is found that the effective number of parliamentary parties in the countries adopting proportional representation system(PR), overall, is apparently larger than that in countries adopting plurality with single-member-district system(SMD), and that in countries holding direct presidential elections is clearly smaller ..

1990年統一前，東德由德國社會主義統一黨進行威權統治，西德則為一個自由民主國家，政黨在公平的競爭制度中運作。兩德統一後，政治制度迥異的兩個體系在重整過程中，必然會出現嚴重的磨合現象。不同於以往探究政黨體系僅重視體系內單純的「相關性政黨數字」的變化，與政黨「意識形態」距離與強度的差異，本論文試著從「社會分歧」(social cleavage)出發，觀察德國統一以來，社會結構分歧程度與政黨反應此基礎所呈現的互動關係，並說明政黨勢力的興衰，如何合作結盟或是分裂結構，已呈現德國政黨體系的內涵特..

Before German unification in 1990, East Germany/GDR was authoritarian-governed by the Socialist Unity Party of Germany and West Germany/FRG was a democratic state with a relatively fair competitive party system. Serious conflicts between totally different political systems must have emerged when they started to become a unified state. Differing from the traditional approach to studying party systems through party numbers and ideologies, the author will, through “social cleavage,” examine how German parties reflect the change of ..