2008年立委選舉候選人票之分析：選民個體與選區總體的多層模型

Abstract

本文藉由多層模型的建構，依據學理將選民個體層次與選區總體層次同時納入模型，檢視2008年立法委員選舉，選民在「單一選區票」之投票抉擇的影響因素。研究結果發現，在選民個體層次上，除了政治世代、省籍、政黨認同、族群認同，以及候選人評價等因素外，在第一家庭身陷風暴的氛圍下，選民對陳水扁的施政滿意度，在投票抉擇上亦有顯著的影響力。這不但呼應了「公民複決理論」或「回溯性投票」的論點，也可作爲此次民進黨敗選的解釋原因之一。在選區總體層次上，選區的失業率、農牧人口比例、縣市首長黨籍以及候選人現任與否，皆顯著影響選民的投票抉擇。尤其，在農牧人口比例愈高的選區，選民有愈高的相對機率投票給國民黨候選人，顯示國民黨傳統上在農業地區透過地方組織動員選民的能力並未完全流失。

Voters are nested in electoral districts and are therefore often affected by the macro-level characteristics of the districts. By incorporating both the individual-level and district-level variables, we construct a two-level model to analyze voters` voting choices on the single-member-district ballot in the 2008 legislative election. We find that indeed some theoretically important variables at both levels play significant roles in voters` decisions. At the micro level, we confirm that candidate evaluation, party identification, political generation, ethnic origin, as well as ethnic identity are significant factors. Furthermore, the evaluation of the then President Chen Shuibian`s performance also figures significantly; that is, the more negative the evaluation is, the less likely it is for a voter to vote for the DPP candidate. This finding fits the expectations from the referendum voting and retrospective voting theories. At the district level, on the other hand, we also find that regardless of whether the candidate is an incumbent legislature, whether the candidate`s party affiliation coincides with that of the county magistrate/city mayor, the unemployment rate in the area, as well as the percentage of population in the farming and fishery industries also affect voters` choices. In particular, we find that in the 2008 legislature election voters in districts with a higher percentage of population in the farming and fishery industries were more likely to vote for the KMT candidates. This may indicate that the KMT has more or less maintained its mobilization capability through local networks in rural areas.