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An adaptive smoothing method for traffic state identification from incomplete information  [PDF]
Martin Treiber,Dirk Helbing
Physics , 2002,
Abstract: We present a new method to obtain spatio-temporal information from aggregated data of stationary traffic detectors, the ``adaptive smoothing method''. In essential, a nonlinear spatio-temporal lowpass filter is applied to the input detector data. This filter exploits the fact that, in congested traffic, perturbations travel upstream at a constant speed, while in free traffic, information propagates downstream. As a result, one obtains velocity, flow, or other traffic variables as smooth functions of space and time. Applications include traffic-state visualization, reconstruction of traffic situations from incomplete information, fast identification of traffic breakdowns (e.g., in incident detection), and experimental verification of traffic models. We apply the adaptive smoothing method to observed congestion patterns on several German freeways. It manages to make sense out of data where conventional visualization techniques fail. By ignoring up to 65% of the detectors and applying the method to the reduced data set, we show that the results are robust. The method works well if the distances between neighbouring detector cross sections do not exceed 3 km.
Online Identification and Tracking of Subspaces from Highly Incomplete Information  [PDF]
Laura Balzano,Robert Nowak,Benjamin Recht
Mathematics , 2010,
Abstract: This work presents GROUSE (Grassmanian Rank-One Update Subspace Estimation), an efficient online algorithm for tracking subspaces from highly incomplete observations. GROUSE requires only basic linear algebraic manipulations at each iteration, and each subspace update can be performed in linear time in the dimension of the subspace. The algorithm is derived by analyzing incremental gradient descent on the Grassmannian manifold of subspaces. With a slight modification, GROUSE can also be used as an online incremental algorithm for the matrix completion problem of imputing missing entries of a low-rank matrix. GROUSE performs exceptionally well in practice both in tracking subspaces and as an online algorithm for matrix completion.
Optimal compression of quantum information for one-qubit source at incomplete data: a new aspect of Jaynes principle  [PDF]
Michal Horodecki,Ryszard Horodecki,Pawel Horodecki
Physics , 1998,
Abstract: We consider the problem of optimal processing of quantum information at incomplete experimental data characterizing the quantum source. In particular, we then prove that for one-qubit quantum source the Jaynes principle offers a simple scheme for optimal compression of quantum information. According to the scheme one should process as if the density matrix of the source were actually equal to the matrix of the Jaynes state.
Locating the source of spreading in complex networks  [PDF]
Zhesi Shen,Shinan Cao,Ying Fan,Zengru Di,Wen-Xu Wang,H. Eugene Stanley
Computer Science , 2015,
Abstract: Locating the sources that trigger a dynamical process is a fundamental but challenging problem in complex networks, ranging from epidemic spreading in society and on the Internet to cancer metastasis in the human body. An accurate localization of the source is inherently limited by our ability to simultaneously access the information of all nodes in a large-scale complex network, such as the time at which each individual is infected in a large population. This thus raises two critical questions: how do we locate the source from incomplete information and can we achieve full localization of sources at any possible location from a given set of observers. Here we develop an efficient algorithm to locate the source of a diffusion-like process and propose a general locatability condition. We test the algorithm by employing epidemic spreading and consensus dynamics as typical dynamical processes and apply it to the H1N1 pandemic in China. We find that the sources can be precisely located in arbitrary networks insofar as the locatability condition is assured. Our tools greatly improve our ability to locate the source of diffusion in complex networks based on limited accessibility of nodal information. Moreover they have implications for controlling a variety of dynamical processes taking place on complex networks, such as inhibiting epidemics, slowing the spread of rumors, and eliminating cancer seed cells in the human body.
Modeling and Analyzing the Interaction between Network Rumors and Authoritative Information  [PDF]
Lingling Xia,Guoping Jiang,Yurong Song,Bo Song
Entropy , 2015, DOI: 10.3390/e17010471
Abstract: In this paper, we propose a novel two-stage rumor spreading Susceptible-Infected-Authoritative-Removed (SIAR) model for complex homogeneous and heterogeneous networks. The interaction Markov chains (IMC) mean-field equations based on the SIAR model are derived to describe the dynamic interaction between the rumors and authoritative information. We use a Monte Carlo simulation method to characterize the dynamics of the Susceptible-Infected-Removed (SIR) and SIAR models, showing that the SIAR model with consideration of authoritative information gives a more realistic description of propagation features of rumors than the SIR model. The simulation results demonstrate that the critical threshold λc of the SIAR model has the tiniest increase than the threshold of SIR model. The sooner the authoritative information is introduced, the less negative impact the rumors will bring. We also get the result that heterogeneous networks are more prone to the spreading of rumors. Additionally, the inhibition of rumor spreading, as one of the characteristics of the new SIAR model itself, is instructive for later studies on the rumor spreading models and the controlling strategies.
The Impact of Incomplete Information on Games in Parallel Relay Networks  [PDF]
Hongda Xiao,Edmund M. Yeh
Computer Science , 2011,
Abstract: We consider the impact of incomplete information on incentives for node cooperation in parallel relay networks with one source node, one destination node, and multiple relay nodes. All nodes are selfish and strategic, interested in maximizing their own profit instead of the social welfare. We consider the practical situation where the channel state on any given relay path is not observable to the source or to the other relays. We examine different bargaining relationships between the source and the relays, and propose a framework for analyzing the efficiency loss induced by incomplete information. We analyze the source of the efficiency loss, and quantify the amount of inefficiency which results.
Rumors and Internet  [cached]
RENARD, Jean-Bruno
Contemporanea : Revista de Comunica??o e Cultura , 2011,
Abstract: This paper will address the rumors and the Internet in two ways: rumors as the subject of the Internet and the Internet as a channel of dissemination of rumors. We define rumors in a broadly way as an unverified information circulating within a social group. In a strict sense, rumors can be understand as false information that people believe. A rumor is an urban myth, a legend, a hoax, or a contemporary narrative, a tale of everyday life, false or dubious, but in which we believed because it is likely, and it conveys a moral message.
Incomplete Information in RDF  [PDF]
Charalampos Nikolaou,Manolis Koubarakis
Computer Science , 2012,
Abstract: We extend RDF with the ability to represent property values that exist, but are unknown or partially known, using constraints. Following ideas from the incomplete information literature, we develop a semantics for this extension of RDF, called RDFi, and study SPARQL query evaluation in this framework.
Incomplete information and correlated electrons  [PDF]
Qiuping A. Wang
Physics , 2002,
Abstract: Although G\"odel's incompleteness theorem made mathematician recognize that no axiomatic system could completely prove its correctness and that there is an eternal hole between our knowledge and the world, physicists so far continue to work on the approaches based on the hypothesis to completely or approximately know the systems of interest. In this paper, however, I review the recent development of a different approach, a statistical theory based upon the notion of incomplete information. This consideration leads to generalized statistical mechanics characterized by an incompleteness parameter which equals unity when information is complete. The mathematical and physical bases of the information incompleteness are discussed. The application of the concomitant incomplete quantum distribution to correlated electron systems is reviewed.
Nonextensive statistics and incomplete information  [PDF]
Qiuping A. Wang
Physics , 2001, DOI: 10.1140/epjb/e20020100
Abstract: We comment on some open questions and theoretical peculiarities in Tsallis nonextensive statistical mechanics. It is shown that the theoretical basis of the successful Tsallis' generalized exponential distribution shows some worrying properties with the conventional normalization and the escort probability. These theoretical difficulties may be avoided by introducing an so called incomplete normalization allowing to deduce Tsallis' generalized distribution in a more convincing and consistent way.
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