There are many reasons why societies run elections. For example, a given society may need
to select its leader (eg, a president), members of a team may need to find an appropriate …

We study two influential voting rules proposed in the 1890s by Phragmen and Thiele, which
elect a committee of k candidates which proportionally represents the voters. Voters provide …

Multiwinner voting rules are used to select a small representative subset of candidates or
items from a larger set given the preferences of voters. However, if candidates have …

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

This paper is an axiomatic study of consistent approval-based multi-winner rules, ie, voting
rules that select a fixed-size group of candidates based on approval ballots. We introduce …

In this paper we introduce a new voting formalism to support long-term collective decision
making: perpetual voting rules. These are voting rules that take the history of previous …

Algorithmic decision-making has become ubiquitous in our societal and economic lives.
With more and more decisions being delegated to algorithms, we have also encountered …

The election methods introduced in 1894–1895 by Phragmén and Thiele, and their
somewhat later versions for ordered (ranked) ballots, are discussed in detail. The paper …

Streaming submodular maximization is a natural model for the task of selecting a
representative subset from a large-scale dataset. If datapoints have sensitive attributes such …

In this paper we extend the principle of proportional representation to rankings. We consider
the setting where alternatives need to be ranked based on approval preferences. In this …