#### Filter Results:

- Full text PDF available (39)

#### Publication Year

2009

2017

- This year (6)
- Last 5 years (45)
- Last 10 years (50)

#### Publication Type

#### Co-author

#### Journals and Conferences

#### Key Phrases

Learn More

We study computational aspects of three prominent voting rules that use approval ballots to elect multiple winners. These rules are satisfaction approval voting, proportional approval voting, and reweighted approval voting. We first show that computing the winner for proportional approval voting is NP-hard, closing a long standing open problem. As none of… (More)

- Nicholas Mattei, Maria Silvia Pini, Francesca Rossi, Kristen Brent Venable
- Annals of Mathematics and Artificial Intelligence
- 2013

We investigate the computational complexity of finding optimal bribery schemes in voting domains where the candidate set is the Cartesian product of a set of variables and voters use CP-nets, an expressive and compact way to represent preferences. To do this, we generalize the traditional bribery problem to take into account several issues over which agents… (More)

- Nicholas Mattei, Toby Walsh
- ADT
- 2013

- Cristina Cornelio, Judy Goldsmith, Nicholas Mattei, Francesca Rossi, Kristen Brent Venable
- Australasian Conference on Artificial…
- 2013

In this paper we present a two-fold generalization of conditional preference networks (CP-nets) that incorporates uncertainty. CP-nets are a formal tool to model qualitative conditional statements (cp-statements) about preferences over a set of objects. They are inherently static structures, both in their ability to capture dependencies between objects and… (More)

- Judy Goldsmith, Jérôme Lang, Nicholas Mattei, Patrice Perny
- AAAI
- 2014

Positional scoring rules in voting compute the score of an alternative by summing the scores for the alternative induced by every vote. This summation principle ensures that all votes contribute equally to the score of an alternative. We relax this assumption and, instead, aggregate scores by taking into account the rank of a score in the ordered list of… (More)

The probabilistic serial (PS) rule is a prominent randomized rule for assigning indivisible goods to agents. Although it is well known for its good fairness and welfare properties, it is not strategyproof. In view of this, we address several fundamental questions regarding equilibria under PS. Firstly, we show that Nash deviations under the PS rule can… (More)

- Nicholas Mattei, Nina Narodytska, Toby Walsh
- ECAI
- 2014

We study the computational complexity of controlling the result of an election by breaking ties strategically. This problem is equivalent to the problem of deciding the winner of an election under parallel universes tie-breaking. When the chair of the election is only asked to break ties to choose between one of the co-winners, the problem is trivially… (More)

- Nicholas Mattei
- IJCAI
- 2011

My research seeks insight into the complexity of computational reasoning under uncertain information. I focus on preference aggregation and social choice. Insights in these areas have broader impacts in the areas of complexity theory, autonomous agents, and uncertainty in artificial intelligence. Motivation: Planning and reasoning in nondeterministic… (More)

- Haris Aziz, Serge Gaspers, Nicholas Mattei, Nina Narodytska, Toby Walsh
- ArXiv
- 2014

The probabilistic serial (PS) rule is one of the most prominent randomized rules for the assignment problem. It is well-known for its superior fairness and welfare properties. However, PS is not immune to manipulative behaviour by the agents. We examine computational and non-computational aspects of strategising under the PS rule. Firstly, we study the… (More)