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View article: Equilibrium Computation in First-Price Auctions with Correlated Priors
Equilibrium Computation in First-Price Auctions with Correlated Priors Open
We consider the computational complexity of computing Bayes-Nash equilibria in first-price auctions, where the bidders' values for the item are drawn from a general (possibly correlated) joint distribution. We show that when the values and…
View article: Equilibrium Computation in First-Price Auctions with Correlated Priors
Equilibrium Computation in First-Price Auctions with Correlated Priors Open
We consider the computational complexity of computing Bayes-Nash equilibria in first-price auctions, where the bidders' values for the item are drawn from a general (possibly correlated) joint distribution. We show that when the values and…
View article: Utilitarian Distortion with Predictions
Utilitarian Distortion with Predictions Open
We study the utilitarian distortion of social choice mechanisms under the recently proposed learning-augmented framework where some (possibly unreliable) predicted information about the preferences of the agents is given as input. In parti…
View article: Optimal Metric Distortion for Matching on the Line
Optimal Metric Distortion for Matching on the Line Open
We study the distortion of one-sided and two-sided matching problems on the line. In the one-sided case, $n$ agents need to be matched to $n$ items, and each agent's cost in a matching is their distance from the item they were matched to. …
View article: Truthful interval covering
Truthful interval covering Open
We initiate the study of a novel problem in mechanism design without money, which we term Truthful Interval Covering (TIC). An instance of TIC consists of a set of agents each associated with an individual interval on a line, and the objec…
View article: HyperDet: Source Detection in Hypergraphs via Interactive Relationship Construction and Feature-rich Attention Fusion
HyperDet: Source Detection in Hypergraphs via Interactive Relationship Construction and Feature-rich Attention Fusion Open
Hypergraphs offer superior modeling capabilities for social networks, particularly in capturing group phenomena that extend beyond pairwise interactions in rumor propagation. Existing approaches in rumor source detection predominantly focu…
View article: On the Computation of Equilibria in Discrete First-Price Auctions
On the Computation of Equilibria in Discrete First-Price Auctions Open
We study the computational complexity of computing Bayes-Nash equilibria in first-price auctions with discrete value distributions and discrete bidding space, under general subjective beliefs. It is known that such auctions do not always h…
View article: Pushing the Frontier on Approximate EFX Allocations
Pushing the Frontier on Approximate EFX Allocations Open
We study the problem of allocating a set of indivisible goods to a set of agents with additive valuation functions, aiming to achieve approximate envy-freeness up to any good ($α$-EFX). The state-of-the-art results on the problem include t…
View article: PPAD-Membership for Problems with Exact Rational Solutions: A General Approach via Convex Optimization
PPAD-Membership for Problems with Exact Rational Solutions: A General Approach via Convex Optimization Open
We introduce a general technique for proving membership of search problems with exact rational solutions in PPAD, one of the most well-known classes containing total search problems with polynomial-time verifiable solutions. In particular,…
View article: AI Driven Online Advertising: Market Design, Generative AI, and Ethics
AI Driven Online Advertising: Market Design, Generative AI, and Ethics Open
Online advertising contributes a considerable part of the tech sector's revenue, and has been remarkably influencing the public agenda. With evolving developments, AI is playing an increasingly significant role in online advertising. We pr…
View article: Revisiting the Distortion of Distributed Voting
Revisiting the Distortion of Distributed Voting Open
We consider a setting with agents that have preferences over alternatives and are partitioned into disjoint districts. The goal is to choose one alternative as the winner using a mechanism which first decides a representative alternative f…
View article: Improved Metric Distortion via Threshold Approvals
Improved Metric Distortion via Threshold Approvals Open
We consider a social choice setting in which agents and alternatives are represented by points in a metric space, and the cost of an agent for an alternative is the distance between the corresponding points in the space. The goal is to cho…
View article: On the Computation of Equilibria in Discrete First-Price Auctions
On the Computation of Equilibria in Discrete First-Price Auctions Open
We study the computational complexity of computing Bayes-Nash equilibria in first-price auctions with discrete value distributions and discrete bidding space, under general subjective beliefs. It is known that such auctions do not always h…
View article: PPAD-membership for Problems with Exact Rational Solutions: A General Approach via Convex Optimization
PPAD-membership for Problems with Exact Rational Solutions: A General Approach via Convex Optimization Open
We introduce a general technique for proving membership of search problems with exact rational solutions in PPAD, one of the most well-known classes containing total search problems with polynomial-time verifiable solutions. In particular,…
View article: On the Potential and Limitations of Proxy Voting: Delegation with Incomplete Votes
On the Potential and Limitations of Proxy Voting: Delegation with Incomplete Votes Open
We study elections where voters are faced with the challenge of expressing preferences over an extreme number of issues under consideration. This is largely motivated by emerging blockchain governance systems, which include voters with dif…
View article: Truthful Interval Covering
Truthful Interval Covering Open
We initiate the study of a novel problem in mechanism design without money, which we term Truthful Interval Covering (TIC). An instance of TIC consists of a set of agents each associated with an individual interval on a line, and the objec…
View article: Improved Metric Distortion via Threshold Approvals
Improved Metric Distortion via Threshold Approvals Open
We consider a social choice setting in which agents and alternatives are represented by points in a metric space, and the cost of an agent for an alternative is the distance between the corresponding points in the space. The goal is to cho…
View article: Consensus-Halving: Does It Ever Get Easier?
Consensus-Halving: Does It Ever Get Easier? Open
In the $\\varepsilon$-Consensus-Halving problem, a fundamental problem in fair\ndivision, there are $n$ agents with valuations over the interval $[0,1]$, and\nthe goal is to divide the interval into pieces and assign a label "$+$" or\n"$-$…
View article: FIXP-Membership via Convex Optimization: Games, Cakes, and Markets
FIXP-Membership via Convex Optimization: Games, Cakes, and Markets Open
We introduce a new technique for proving membership of problems in FIXP - the class capturing the complexity of computing a fixed-point of an algebraic circuit. Our technique constructs a "pseudogate" which can be used as a black box when …
View article: Heterogeneous facility location with limited resources
Heterogeneous facility location with limited resources Open
We initiate the study of the heterogeneous facility location problem with limited resources. We mainly focus on the fundamental case where a set of agents are positioned in the line segment [0,1] and have approval preferences over two avai…
View article: On the Complexity of Equilibrium Computation in First-Price Auctions
On the Complexity of Equilibrium Computation in First-Price Auctions Open
We consider the problem of computing a (pure) Bayes-Nash equilibrium in the\nfirst-price auction with continuous value distributions and discrete bidding\nspace. We prove that when bidders have independent subjective prior beliefs\nabout t…
View article: Revisiting the Distortion of Distributed Voting
Revisiting the Distortion of Distributed Voting Open
We consider a setting with agents that have preferences over alternatives and are partitioned into disjoint districts. The goal is to choose one alternative as the winner using a mechanism which first decides a representative alternative f…
View article: Settling the Distortion of Distributed Facility Location
Settling the Distortion of Distributed Facility Location Open
We study the distributed facility location problem, where a set of agents with positions on the line of real numbers are partitioned into disjoint districts, and the goal is to choose a point to satisfy certain criteria, such as optimize a…