Traditionally, social choice theory has only been applicable to choices among a few
predetermined alternatives but not to more complex decisions such as collectively selecting …

In this survey, we review the literature investigating participatory budgeting as a social
choice problem. Participatory Budgeting (PB) is a democratic process in which citizens are …

When selecting a subset of candidates (a so-called committee) based on the preferences of
voters, proportional representation is often a major desideratum. When going beyond …

A voting rule decides on a probability distribution over a set of m alternatives, based on
rankings of those alternatives provided by agents. We assume that agents have cardinal …

The ability to measure the satisfaction of (groups of) voters is a crucial prerequisite for
formulating proportionality axioms in approval-based participatory budgeting elections. Two …

In the late 19th century, Swedish mathematician Edvard Phragmén proposed a load-
balancing approach for selecting committees based on approval ballots. We consider three …

We study the problem of fair sequential decision making given voter preferences. In each
round, a decision rule must choose a decision from a set of alternatives where each voter …

We provide a library of participatory budgeting data (Pabulib) and open source tools
(Pabutools and Pabustats) for analysing this data. We analyse how the results of …

Participatory budgeting engages the public in the process of allocating public money to
different types of projects. PB designs differ in how voters are asked to express their …

We introduce a novel definition for a small set R of k points being" representative" of a larger
set in a metric space. Given a set V (eg, documents or voters) to represent, and a set C of …