Abdallah Saffidine

Score bounded Monte-Carlo tree search

Monte-Carlo Tree Search (MCTS) is a successful algorithm used in many state of the art game engines. We propose to improve a MCTS solver when a game has more than two outcomes. It is for example the case in games that can end in draw positions. In this case it improves significantly a MCTS solver to take into account bounds on the possible scores of a node in order to select the nodes to explore. We apply our algorithm to solving Seki in the game of Go and to Connect Four.

Solving breakthrough with Race Patterns and Job-Level Proof Number Search

breakthrough is a recent race-based board game usually played on a 8×8 board. We describe a method to solve 6×5 boards based on (1) race patterns and (2) an extension of (JLPNS).

Choosing collectively optimal sets of alternatives based on the condorcet criterion

In elections, an alternative is said to be a Condorcet winner if it is preferred to any other alternative by a majority of voters. While this is a very attractive solution concept, many elections do not have a Condorcet winner. In this paper, we propose a setvalued relaxation of this concept, which we call a Condorcet winning set: such sets consist of alternatives that collectively dominate any other alternative. We also consider a more general version of this concept, where instead of domination by a majority of voters we require domination by a given fraction Θ of voters; we refer to this concept as Θ-winning set. We explore social choice-theoretic and algorithmic aspects of these solution concepts, both theoretically and empirically.

Condorcet winning sets

An alternative is said to be a Condorcet winner of an election if it is preferred to any other alternative by a majority of voters. While this is a very attractive solution concept, many elections do not have a Condorcet winner. In this paper, we propose a set-valued relaxation of this concept, which we call a Condorcet winning set: such sets consist of alternatives that collectively dominate any other alternative. We also consider a more general version of this concept, where instead of domination by a majority of voters we require domination by a given fraction

Material Symmetry to Partition Endgame Tables

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Positional scoring-based allocation of indivisible goods

θ of voters; we refer to such sets as

Mechanisms for Online Organ Matching

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