Welfare Analysis of Legislative Redistricting

立法选区重划的福利分析

• 批准号: 0452561
• 负责人: Brian Knight
• 金额: $ 26.63万
• 依托单位: National Bureau of Economic Research Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0452561&HistoricalAwards=false
• 关键词: Welfare; Analysis; Legislative; Redistricting

Recent Supreme Court cases involving both racial and partisan gerrymandering have intensified a national debate over legislative redistricting. There is little agreement, however, in this debate over how alternative redistricting plans should be evaluated from the perspective of promoting the interests of voters. At its most fundamental level, the relevant question is: how should legislatures represent different groups of voters, and how should voters be allocated across districts in order to implement this prescription? This project develops an approach based upon traditional welfare economics in order to address this question and related questions from both a theoretical and empirical perspective. As a normative benchmark, the principal investigators begin by examining how ideological groups should be represented in legislatures. The key findings are that the seats-votes curve, which relates the fraction of seats held by the leftist party to its national support, should be linear, have a positive slope, and be biased in favor of the dominant party. They then examine how voters should be allocated across districts in order to implement this optimal seats-votes curve. The key findings here are that, if the optimal seats-votes curve can be implemented, then districts should be heterogeneous in their allocation of voter ideologies and that some districts should be "safe seats". Finally, the project will develop conditions under which the optimal seats-votes curve can be implemented and then tackle the difficult question of how voters should be allocated across districts when these conditions are not satisfied. The research team will also develop an integrated theoretical and empirical approach to evaluating legislative redistricting from this welfare perspective. It first develops a methodology for estimating seats-votes curves; this methodology requires only data on district-by-district support for the leftist party in legislative elections. The researchers then demonstrate that voter welfare can be directly measured for this observed seats-votes curve as well as for any other possible seats-votes curve. Thus, observed voter welfare can be compared with voter welfare under the optimal seats-votes curve, permitting measurement of any welfare losses from sub-optimal redistricting. In addition, observed voter welfare can be compared with voter welfare under proportional representation, an alternative voting system commonly used in other countries. The methodology also permits a comparison of voter welfare under alternative redistricting regimes, including bipartisan, partisan, and independent commissions. Finally, these ideas are illustrated in an application to voting in U.S. state legislative elections. The third project aims to generalize the ideas developed in the first two parts to a framework in which both voters and candidates are defined by their ideology as well as by their race. This generalized framework will be used address several normative questions related to race in redistricting. For example, how should black voters be represented in legislatures and allocated across districts? While black majority districts tend to elect black candidates, they also concentrate liberal voters, potentially leading to the defeat of leftist candidates in other districts. Thus, we plan to examine this and other potentially interesting interactions between race and ideology.

最近最高法院涉及种族和党派不公正划分选区的案件加剧了全国关于立法机构重新划分选区的辩论。然而，对于如何从促进选民利益的角度来评估不同的选区重新划分计划，在这场辩论中几乎没有达成一致。在最基本的层面上，相关的问题是：立法机构应该如何代表不同的选民群体，选民应该如何分配到不同的地区，以实施这一处方？本项目发展了一种基于传统福利经济学的方法，以便从理论和实证的角度解决这个问题和相关问题。作为规范基准，主要调查人员首先研究意识形态团体应该如何在立法机构中得到代表。主要发现是，席位-选票曲线，即左翼政党所占席位比例与其全国支持率之间的关系，应该是线性的，具有正斜率，并且偏向于优势政党。然后，他们研究如何在各个地区分配选民，以实现这一最佳席位-选票曲线。本文的主要发现是，如果可以实现最优席位-选票曲线，那么选区在选民意识形态的分配上应该是异质的，并且一些选区应该是“安全席位”。最后，该项目将开发可实施最佳席位-选票曲线的条件，然后解决在这些条件不满足时如何跨地区分配选民的难题。研究小组还将开发一种综合的理论和实证方法，从福利的角度来评估立法区重划。它首先开发了一种估算席位-投票曲线的方法；这种方法只需要左翼政党在立法选举中逐区支持率的数据。研究人员随后证明，选民福利可以通过观察到的席位-投票曲线以及任何其他可能的席位-投票曲线直接衡量。因此，观察到的选民福利可以与最优席位-选票曲线下的选民福利进行比较，从而可以测量次优选区重划造成的任何福利损失。此外，观察到的选民福利可以与比例代表制下的选民福利进行比较，比例代表制是其他国家常用的另一种投票制度。该方法还允许比较不同的选区划分制度下的选民福利，包括两党、党派和独立委员会。最后，这些思想在美国州立法选举投票中的应用进行了说明。第三个项目旨在将前两部分的观点概括为一个框架，在这个框架中，选民和候选人都是由他们的意识形态和种族来定义的。这一广义框架将用于处理与重新划分选区的种族有关的几个规范性问题。例如，黑人选民应该如何在立法机构中得到代表，如何在各个地区分配？虽然黑人占多数的地区倾向于选举黑人候选人，但他们也集中了自由派选民，这可能导致其他地区的左派候选人失败。因此，我们计划研究种族和意识形态之间的这种和其他可能有趣的相互作用。