A Majoritarian Representative Voting System

TL;DR

This paper introduces a flexible voting system that combines features of proportional and majoritarian systems, allowing for more representative yet decisive election outcomes, supported by theoretical analysis and simulations.

Contribution

It proposes a convex space of hybrid voting systems and an algorithm to produce the most majoritarian result within this space.

Findings

System produces results comparable to majoritarian voting.

Tends to generate a dominant first party with exponentially decreasing smaller parties.

System can be adapted for bicameral parliamentary structures.

Abstract

We present an alternative voting system that aims at bridging the gap between proportional representative systems and majoritarian, single winner election systems. The system lets people vote for multiple parties, but then assigns each ballot to a single party. This opens a whole range of possible systems, all representative. We show theoretically that this space is convex. Then among the possible parliaments we present an algorithm to produce the most majoritarian result. We then test the system and compare the results with a pure proportional and a majoritarian voting system showing how the results are comparable with the majoritarian system. Then we simulate the system and show how it tends to produce parties of exponentially decreasing size with always a first, major party. Finally we describe how the system can be used in a context of a parliament made up of two separate houses.