Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
In this paper, we introduce a cooperative game model arising from bin covering problem, called bin covering game, and discuss the computational complexity issues on the core and the approximate core of the game. Making use of duality theorem of linear programming, a sufficient and necessary condition on core nonemptiness is proposed. When the core is empty, a lower bound on the minimum taxrate of...
We give a test that can distinguish efficiently between product states of n quantum systems and states which are far from product. If applied to a state |φ) whose maximum overlap with a product state is 1- ε, the test passes with probability 1-Θ(ε), regardless of n or the local dimensions of the individual systems. The test uses two copies of |φ). We prove correctness of this test as a special case...
The Coin Problem is the following problem: a coin is given, which lands on head with probability either 1/2 + β or 1/2 - β. We are given the outcome of n independent tosses of this coin, and the goal is to guess which way the coin is biased, and to answer correctly with probability ≥ 2/3. When our computational model is unrestricted, the majority function is optimal, and succeeds when β ≥ c/√n for...
We present a new algorithm for Unique Games which is based on purely spectral techniques, in contrast to previous work in the area, which relies heavily on semidefinite programming (SDP). Given a highly satisfiable instance of Unique Games, our algorithm is able to recover a good assignment. The approximation guarantee depends only on the completeness of the game, and not on the alphabet size, while...
We show that if Arthur-Merlin protocols can be derandomized, then there is a Boolean function computable in deterministic exponential-time with access to an NP oracle, that cannot be computed by Boolean circuits of exponential size. More formally, if prAM ⊆ PNP then there is a Boolean function in ENP that requires circuits of size 2Ω(n). prAM is the class of promise problems that have Arthur-Merlin...
In this paper, we consider the problem of measurement allocation in a spatially correlated sensor field. Our objective is to determine the probability of each sensor's being measured for improved observability; the sensor located at less correlated area should be assigned more probability. To this end, we quantify the level of correlation of each sensor through the mutual information criterion reflecting...
In a landmark paper, Papadimitriou introduced a number of syntactic subclasses of TFNP based on proof styles that (unlike TFNP) admit complete problems. A recent series of results has shown that finding Nash equilibria is complete for PPAD, a particularly notable subclass of TFNP. A major goal of this work is to expand the universe of known PPAD-complete problems. We resolve the computational complexity...
This paper ties the line of work on algorithms that find an O(??(log n))-approximation to the SPARSEST CUT together with the line of work on algorithms that run in subquadratic time by using only single-commodity flows. We present an algorithm that simultaneously achieves both goals, finding an O(??(log (n)/??))-approximation using O(n?? logO(1) n) max-flows. The core of the algorithm is a stronger,...
With the work of Khot and Vishnoi as a starting point, we obtain integrality gaps for certain strong SDP relaxations of Unique Games. Specifically, we exhibit a Unique Games gap instance for the basic semidefinite program strengthened by all valid linear inequalities on the inner products of up to exp(??(log log n)1/4) vectors. For a stronger relaxation obtained from the basic semidefinite program...
In this paper we consider the problem of maximizing the number of supported connections in arbitrary wireless networks where a transmission is supported if and only if the signal-to-interference-plus-noise ratio at the receiver is greater than some threshold. The aim is to choose transmission powers for each connection so as to maximize the number of connections for which this threshold is met. We...
We show that there is a polynomial-time approximation scheme for computing Nash equilibria in anonymous games with any fixed number of strategies (a very broad and important class of games), extending the two-strategy result of Daskalakis and Papadimitriou 2007. The approximation guarantee follows from a probabilistic result of more general interest: The distribution of the sum of n independent unit...
We show a connection between the semidefinite relaxation of unique games and their behavior under parallel repetition. Specifically,denoting by val(G) the value of a two-prover unique game G, andby sdpval(G) the value of a natural semidefinite program to approximate val(G), we prove that for every l epsi N, if sdpval(G) ges 1-delta, then val(Gl) ges 1-radicsldelta. Here, Gl denotes the l-fold parallel...
The parallel repetition theorem states that for any two-prover game, with value 1 - isin (for, say, isin les 1/2), the value of the game repeated in parallel n times is at most (1 - isinc)Omega(n/s), where s is the answers' length (of the original game) and c is a universal constant. Several researchers asked wether this bound could be improved to (1 - isin)Omega(n/s); this question is usually referred...
In the kernel clustering problem we are given a large ntimesn positive semi-definite matrix A=(aij) with Sigmai,jn=1 aij=0 and a small ktimesk positivesemi-definite matrix B=bij. The goal is to find a partition S1,..Sk of {1,...n} which maximizes the quantity Sigmai,j=1k(Sigma(i,j)isinSitimesSj). We study the computational complexity of this generic clustering problem which originates in the...
We investigate the notions of may- and must-approximation in Erratic Idealized Algol (a nondeterministic extension of Idealized Algol), and give explicit characterizations of both using its game model. Notably, must-approximation is captured by a novel preorder on nondeterministic strategies, whose definition is formulated in terms of winning regions in a reachability game. The game is played on traces...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.