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Related papers: On Hats and other Covers

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This paper studies Ebert's hat problem for three and four players and two colors, where the probabilities of the colors may be different for each player. Our goal is to maximize the probability of winning the game and to describe winning…

Combinatorics · Mathematics 2024-03-27 Theo van Uem

In this note, we give an explicit polynomial-time executable strategy for Peter Winkler's hat guessing game that gives superior results if the distribution of hats is imbalanced. While Winkler's strategy guarantees in any case that $\lfloor…

Combinatorics · Mathematics 2013-03-29 Benjamin Doerr

This paper studies Ebert's hat problem with four players and two colors, where the probabilities of the colors may be different for each player. Our goal is to maximize the probability of winning the game and to describe winning strategies…

Combinatorics · Mathematics 2023-06-26 Theo van Uem

We initiate the study of the hat guessing number of a graph where the adversary is only allowed to provide a proper coloring of the graph. This is the largest number $q$ for which there is a guessing strategy on each vertex that only…

We study the hat guessing game on graphs. In this game, a player is placed on each vertex $v$ of a graph $G$ and assigned a colored hat from $h(v)$ possible colors. Each player makes a deterministic guess on their hat color based on the…

Combinatorics · Mathematics 2023-12-05 Jeremy Chizewer , I. M. J. McInnis , Mehrdad Sohrabi , Shriya Kaistha

In this paper we study the Three Hat Problem which appeared in Puzzle Corner of the Technology Review magazine. This puzzle gives a scenario in which three players wearing hats are sitting together and each hat can be seen by everyone…

History and Overview · Mathematics 2007-10-16 Brian Benson , Yang Wang

We consider Lionel Levine's notorious hat puzzle with two players. Each player has a stack of hats on their head, and each hat is chosen independently to be either black or white. After observing only the other player's hats, players…

Probability · Mathematics 2025-03-13 Steven Heilman , Omer Tamuz

We discuss ``puzzles of prisoners and hats`` with infinitely many prisoners and more than two hat colors. Assuming that the set of hat colors is equipped with a commutative group structure, we prove strategic equivalence among puzzles of…

Logic · Mathematics 2019-11-11 Masaru Kada , Souji Shizuma

We study the hat chromatic number of a graph defined in the following way: there is one player at each vertex of a loopless graph $G$, an adversary places a hat of one of $K$ colors on the head of each player, two players can see each…

Combinatorics · Mathematics 2019-05-13 Bartłomiej Bosek , Andrzej Dudek , Michał Farnik , Jarosław Grytczuk , Przemysław Mazur

2023 undergraduate thesis on a deterministic "hat game." For a digraph $D$, each player stands on a vertex $v$, is assigned a hat from $h(v)$ possible colors, and makes $g(v)$ guesses of her hat's color based on her out-neighbors' hats. If…

Combinatorics · Mathematics 2025-07-30 I. M. J. McInnis

Lionel Levine's hat challenge has $t$ players, each with a (very large, or infinite) stack of hats on their head, each hat independently colored at random black or white. The players are allowed to coordinate before the random colors are…

Combinatorics · Mathematics 2021-03-10 Ehud Friedgut , Gil Kalai , Guy Kindler

This paper studies asymmetric Ebert's Hat Problem with five players where the probability of the colors may be unequal. We obtain maximal winning probabilities and optimal winning strategies using the concept of adequate sets.

Combinatorics · Mathematics 2023-06-07 Theo van Uem

Lionel Levine's hat challenge has $t$ players, each with a (very large, or infinite) stack of hats on their head, each hat independently colored at random black or white. The players are allowed to coordinate before the random colors are…

Combinatorics · Mathematics 2023-08-22 Noga Alon , Ehud Friedgut , Gil Kalai , Guy Kindler

We study two-player games with alternating moves played on infinite trees. Our main focus is on the case where the trees are full (regular) and the winning set is open (with respect to the product topology on the tree). Gale and Stewart…

Optimization and Control · Mathematics 2026-02-17 Dean Kraizberg

We study the Levine hat problem, a cooperative puzzle introduced by Lionel Levine in 2010, in which $n \geq 2$ players must simultaneously identify a black hat on their own infinite stack, each seeing only their teammates' stacks. While the…

Combinatorics · Mathematics 2026-04-21 Clément Bouquet , Salah Chikhi , Timothé Charles , Yanghao Zhou , Eric Wang

We start with the well-known game below: Two players hold a sheet of paper to their forehead on which a positive integer is written. The numbers are consecutive and each player can only see the number of the other one. In each time step,…

Combinatorics · Mathematics 2013-02-26 Felix Günther , Irina Mustata

We consider a matching problem, which is meaningful in team competitions, as well as in information theory, recommender systems, and assignment problems. In the competitions which we study, each competitor in a team order plays a match with…

Computer Science and Game Theory · Computer Science 2026-05-21 Haris Aziz , Jiarui Gan , Grzegorz Lisowski , Ali Pourmiri

In repeated games, players choose actions concurrently at each step. We consider a parameterized setting of repeated games in which the players form a population of an arbitrary size. Their utility functions encode a reachability objective.…

Computer Science and Game Theory · Computer Science 2025-10-06 Nathalie Bertrand , Patricia Bouyer , Luc Lapointe , Corto Mascle

The network coloring game has been proposed in the literature of social sciences as a model for conflict-resolution circumstances. The players of the game are the vertices of a graph with $n$ vertices and maximum degree $\Delta$. The game…

Discrete Mathematics · Computer Science 2022-04-01 Nikolaos Fryganiotis , Symeon Papavassiliou , Christos Pelekis

In a guessing game, players guess the value of a random real number selected using some probability density function. The winner may be determined in various ways; for example, a winner can be a player whose guess is closest in magnitude to…

Computer Science and Game Theory · Computer Science 2016-07-11 Anthony Mendes , Kent E. Morrison