Person Votes in Norwegian Local Elections, 2003-2015

Incumbents tend to have a solid electoral advantage in candidate-centered electoral settings. Do similar incumbency effects exist in more party-centered environments? We estimate incumbency effects in an open-list proportional representation system, exploiting that seats are first allocated across parties, and then to candidates within party lists. Using data from Norwegian local elections 2003–2015, we document that a candidate that barely wins a seat in the local council has about a 9 percentage points (43%) higher probability of being elected in the next election compared to a candidate that just misses out on a seat on the same party list. We find no evidence that voters contribute to this personal incumbency advantage. Rather, it seems as if party elites are instrumental in securing the electoral success of their party affiliates. We show that incumbents and non-incumbents run again in the subsequent election at about equal rates, but that incumbents tend to advance in the party hierarchy and obtain safer ballot positions in future elections, which is what ultimately leads to electoral success.

在以候选人为中心的选举环境中，现任议员往往拥有稳固的选举优势。那么在更为侧重政党的选举环境中，是否也存在类似的在任优势效应？本研究针对公开名单比例代表制（open-list proportional representation）下的在任优势效应展开估算，该选举规则下席位首先按政党分配，随后再分配给政党名单内的候选人。本研究使用2003至2015年挪威地方选举数据，研究发现：在同一政党名单内，勉强获得地方议会席位的候选人，其在下一届选举中当选的概率比险些错失席位的候选人高出约9个百分点（增幅达43%）。研究未发现选民对这类个人在任优势存在推动作用的证据；相反，助力其党派成员获得选举成功的似乎是政党精英。本研究还表明，现任议员与非现任议员参与后续选举的比例大致相当，但现任议员往往能在政党层级体系中获得晋升，并在后续选举中获得更安全的选票位次，而这正是最终带来选举成功的核心因素。