勸退參選的賽局分析-政黨利益模型

Abstract

綜觀國內大多數的選舉情形，不論是縣市長或是立法委員之選舉，我們常可以看到黨內高層人員為了提高選舉勝選機會，而勸退參選人的相關新聞報導。之前王智賢（2007）一文也探討過相關議題，其探討重點主要置於單純的黨內選舉，然而為使模型與現況更趨於一致，另外將政黨利益加入模型中做更進一步的分析。本文以賽局模型中的序列均衡（sequential equilibrium）之概念，解釋政黨勸退現象，且提出當黨內初選的職位愈高、競爭者與外在競爭之勝選機率愈高或是他黨參選的實力愈低時，就愈不易產生出現勸退參選者之均衡狀況。

After observing most elections in Taiwan, including the elections of the mayor, the head of the county and the legislators, it is very often for us to find those reports about that the authorities of the party dissuade the beginning candidates from running for the elections in order to raise the winning chance in elections. Jue-Shyan（2007）once discussed this correlative issue, and the focus of his paper is those elections that are only inside the party. However, to make the model in accord with the current conditions, we put another variable, the gain from the winning candidate of the same party, into the model to do further analyses. This paper establishes a model of game theory by using the concept of sequential equilibrium to explain the phenomenon in which authorities of the party dissuade the beginning candidates from running for the elections. Besides, it also points out that it is more difficult for the authorities to dissuade candidates from running for elections under the following conditions: the position in the party to be campaigned is higher, the winning probability of competing with other party is higher, and the opponent of the other party is not tough.