Organizatorzy

dr Oskar Skibski
dr hab. Piotr Skowron

Informacje

czwartki, 10:15 , sala: 4050

Dziedziny badań

Lista referatów

18 maja 2023 12:15
Natalia Kucharczuk (University of Warsaw)
Group Vitality Indices and the Shapley Value
We will start the presentation by showing a link between Vitality Indices and Shapley Value-based induced game-theoretic centralities. It is a foundation of our current research regarding extending vitality indices into groups. We propose novel …
4 maja 2023 12:00
Grzegorz Pierczyński (University of Warsaw)
Market-Based Explanations of Collective Decisions
We consider approval-based committee elections, in which a size-k subset of available candidates must be selected given approval sets for each voter, indicating the candidates approved by the voter. A number of axioms capturing ideas …
23 marca 2023 12:15
Jorge Salas (Pontificia Universidad Católica de Chile & University of Edinburgh)
How Do Centrality Measures Choose the Root of Trees?
Centrality measures are widely used to assign importance to graph-structured data. Recently, understanding the principles of such measures has attracted a lot of attention. Given that measures are diverse, this research has usually focused on …
16 marca 2023 12:15
Stanisław Szufa (AGH, Kraków)
Spoiler Susceptibility in Party Elections
An electoral spoiler is usually defined as a losing candidate whose removal would affect the outcome by changing the winner. So far spoiler effects have been analyzed primarily for single-winner electoral systems. We consider this …
2 marca 2023 12:00
Sonja Kraiczy (University of Oxford)
Properties of the Mallows Model Depending on the Number of Alternatives: A Warning for an Experimentalist
The Mallows model is a popular distribution for ranked data. We empirically and theoretically analyze how the properties of rankings sampled from the Mallows model change when increasing the number of alternatives. We find that …
2 lutego 2023 12:00
Oskar Skibski (University of Warsaw)
Closeness centrality via the Condorcet principle
We provide a characterization of closeness centrality in the class of distance-based centralities. To this end, we introduce a natural property, called majority comparison, that states that out of two adjacent nodes the one closer …
12 stycznia 2023 12:15
Michał Pawłowski (University of Warsaw)
Optimizing ride-hailing fares using computational microeconomy tools
Pricing ride-hailing fares sparked a rich line of work in computer science due to its complexity and multidimensionality of aspects. We add to this line of research by considering the model presented by Hikima et …
5 stycznia 2023 12:00
Piotr Faliszewski (AGH University in Kraków)
Map of Elections: Diversity, Polarization, and Agreement In Elections
In this talk I will present the idea of the map of (ordinal) elections and argue what it is good for. First, we will spend considerable amount of time on understanding diversity, polarization, and agreement …
15 grudnia 2022 12:15
Stanisław Kaźmierowski (University of Warsaw)
Algorithm for solving the attack and interception game on networks
The paper "Attack and interception in networks" (F. Bloch, K. Chatterjee, B. Dutta, 2022), describes a game where a single attacker chooses a target and a path and each node chooses a level of protection. …
8 grudnia 2022 12:00
Piotr Skowron (Uniwersytet Warszawski)
Proportionality in General Social Choice Models
We consider a model where a number of candidates need to be selected subject to certain feasibility constraints. The model generalises committee elections (where there is a single constraint on the number of candidates that …
17 listopada 2022 12:15
Piotr Skowron (University of Warsaw)
Proportional Participatory Budgeting with Additive Utilities
We study voting rules for participatory budgeting, where a group of voters collectively decides which projects should be funded using a common budget. We allow the projects to have arbitrary costs, and the voters to …
3 listopada 2022 12:00
Łukasz Janeczko (AGH)
Ties in Multiwinner Approval Voting
We investigate ties in multiwinner approval voting both theoretically and experimentally. Specifically, we analyze the computational complexity of 1) determining if there is a tie in a given election for a given rule, and 2) …
20 października 2022 12:15
Jannik Peters (TU Berlin)
Proportional Participatory Budgeting with Approval-Based Satisfaction Functions
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 common -- but very different -- ways to measure the satisfaction …
13 października 2022 12:15
Michał Tomasz Godziszewski (University of Warsaw)
Election control for VCR Euclidean preferences
Election control problems model situations where some entity (traditionally called the election chair) wants to ensure some agent's victory (the so-called, Constructive Control) or loss (the so-called Destructive Control) by either adding or deleting candidates …
6 października 2022 12:00
Marcin Dziubiński (University of Warsaw)
Selecting a Winner with Impartial Referees
We consider a problem of mechanism design without money, where a planner selects a winner among a set of agents with binary types and receives outside signals (like the report of impartial referees). We show …