86 citations · 165 across the 19 of their papers we have counts for
20 papers
Anticipating Responsibility in Multiagent Planning
Timothy Parker, Umberto Grandi, Emiliano Lorini
Responsibility anticipation is the process of determining if the actions of an individual agent may cause it to be responsible for a particular outcome. This can be used in a multi…
Measuring and Controlling Divisiveness in Rank Aggregation
Rachael Colley, Umberto Grandi, César Hidalgo +2
In rank aggregation, members of a population rank issues to decide which are collectively preferred. We focus instead on identifying divisive issues that express disagreements amon…
Understanding Political Divisiveness using Online Participation data from the 2022 French and Brazilian Presidential Elections
Carlos Navarrete, Mariana Macedo, Rachael Colley +8
Digital technologies can augment civic participation by facilitating the expression of detailed political preferences. Yet, digital participation efforts often rely on methods opti…
Logic-Based Ethical Planning
Umberto Grandi, Emiliano Lorini, Timothy Parker +1
In this paper we propose a framework for ethical decision making in the context of planning, with intended application to robotics. We put forward a compact but highly expressive l…
On the Complexity of Majority Illusion in Social Networks
Umberto Grandi, Grzegorz Lisowski, M. S. Ramanujan +1
Majority illusion occurs in a social network when the majority of the network nodes belong to a certain type but each node's neighbours mostly belong to a different type, therefore…
Collective discrete optimisation as judgment aggregation
Linus Boes, Rachael Colley, Umberto Grandi +2
Many important collective decision-making problems can be seen as multi-agent versions of discrete optimisation problems. Participatory budgeting, for instance, is the collective v…
Unravelling multi-agent ranked delegations
Rachael Colley, Umberto Grandi, Arianna Novaro
We introduce a voting model with multi-agent ranked delegations. This model generalises liquid democracy in two aspects: first, an agent's delegation can use the votes of multiple…
Social Choice Methods for Database Aggregation
Francesco Belardinelli, Umberto Grandi
Knowledge can be represented compactly in multiple ways, from a set of propositional formulas, to a Kripke model, to a database. In this paper we study the aggregation of informati…
Aggregation in Value-Based Argumentation Frameworks
Grzegorz Lisowski, Sylvie Doutre, Umberto Grandi
Value-based argumentation enhances a classical abstract argumentation graph - in which arguments are modelled as nodes connected by directed arrows called attacks - with labels on…
Agent-Mediated Social Choice
Umberto Grandi
Direct democracy is often proposed as a possible solution to the 21st-century problems of democracy. However, this suggestion clashes with the size and complexity of 21st-century s…
Database Aggregation
Francesco Belardinelli, Umberto Grandi
Knowledge can be represented compactly in a multitude ways, from a set of propositional formulas, to a Kripke model, to a database. In this paper we study the aggregation of inform…
Relaxing Exclusive Control in Boolean Games
Francesco Belardinelli, Umberto Grandi, Andreas Herzig +4
In the typical framework for boolean games (BG) each player can change the truth value of some propositional atoms, while attempting to make her goal true. In standard BG goals are…
Cognitive Hierarchy and Voting Manipulation
Edith Elkind, Umberto Grandi, Francesca Rossi +1
By the Gibbard--Satterthwaite theorem, every reasonable voting rule for three or more alternatives is susceptible to manipulation: there exist elections where one or more voters ca…
Gibbard-Satterthwaite Games for k-Approval Voting Rules
Umberto Grandi, Daniel Hughes, Francesca Rossi +1
The Gibbard-Satterthwaite theorem implies the existence of voters, called manipulators, who can change the election outcome in their favour by voting strategically. When a given pr…
Graph Aggregation
Ulle Endriss, Umberto Grandi
Graph aggregation is the process of computing a single output graph that constitutes a good compromise between several input graphs, each provided by a different source. One needs…
A network-based rating system and its resistance to bribery
Umberto Grandi, Paolo Turrini
We study a rating system in which a set of individuals (e.g., the customers of a restaurant) evaluate a given service (e.g, the restaurant), with their aggregated opinion determini…
The Common Structure of Paradoxes in Aggregation Theory
Umberto Grandi
In this paper we analyse some of the classical paradoxes in Social Choice Theory (namely, the Condorcet paradox, the discursive dilemma, the Ostrogorski paradox and the multiple el…
Equilibrium Refinement through Negotiation in Binary Voting
Umberto Grandi, Davide Grossi, Paolo Turrini
We study voting games on binary issues, where voters hold an objective over the outcome of the collective decision and are allowed, before the vote takes place, to negotiate their…
Complexity of Judgment Aggregation
Ulle Endriss, Umberto Grandi, Daniele Porello
We analyse the computational complexity of three problems in judgment aggregation: (1) computing a collective judgment from a profile of individual judgments (the winner determinat…
Restricted Manipulation in Iterative Voting: Convergence and Condorcet Efficiency
Umberto Grandi, Andrea Loreggia, Francesca Rossi +2
In collective decision making, where a voting rule is used to take a collective decision among a group of agents, manipulation by one or more agents is usually considered negative…