Results 11 - 20 of 1,174

Random walks in time-graphs

by Utku Günay Acer, Petros Drineas, Alhussein A. Abouzeid - in Proc. 2nd Int. Workshop on Mobile Opportunistic Networking, 2010
"... Dynamic networks are characterized by topologies that vary with time and are represented by time-graphs. The notion of connectivity in time-graphs is fundamentally different than that in static graphs. End-to-end connectivity is achieved opportunistically by store-forward-carry paradigm if the netwo ..."
Abstract - Cited by 10 (0 self) - Add to MetaCart
walk on this graph has a small hitting time. In this paper, we investigate a similar metric for time-graphs, which indicates how quickly opportunistic methods deliver packets to destinations, speed of convergence in estimating an entity and quickness in the online optimization of protocol parameters

ON DYNAMICAL GAUSSIAN RANDOM WALKS

by Davar Khoshnevisan, David A. Levin, Pedro J. M Éndez-hernández
"... Abstract. Motivated by the recent work of Benjamini, Häggström, Peres, and Steif (2003) on dynamical random walks, we: (i) Prove that, after a suitable normalization, the dynamical Gaussian walk converges weakly to the Ornstein–Uhlenbeck process in classical Wiener space; (ii) derive sharp tailasymp ..."
Abstract - Cited by 3 (0 self) - Add to MetaCart
in classical Wiener space. The results of this paper give a partial affirmative answer to the problem, raised in Benjamini et al. (2003, Question 4) of whether there are precise connections between the OU process in classical Wiener space and dynamical random walks.

Small-space controllability of a walking humanoid robot

by Sébastien Dalibard, Antonio El Khoury, Florent Lamiraux, Michel Taïx, Jean-paul Laumond - in ‘Humanoid Robots (Humanoids), 2011 11th IEEE-RAS International Conference on’, IEEE , 2011
"... Abstract—This paper presents a two-stage motion planner for walking humanoid robots. A first draft path is computed using random motion planning techniques that ensure collision avoidance. In a second step, the draft path is approximated by a whole-body dynamically stable walk trajectory. The contri ..."
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Abstract—This paper presents a two-stage motion planner for walking humanoid robots. A first draft path is computed using random motion planning techniques that ensure collision avoidance. In a second step, the draft path is approximated by a whole-body dynamically stable walk trajectory

On the Embeddability of Random Walk Distances

by Xiaohan Zhao, Adelbert Chang, Atish Das Sarma, Haitao Zheng, Ben Y. Zhao
"... Analysis of large graphs is critical to the ongoing growth of search engines and social networks. One class of queries centers around node affinity, often quantified by random-walk distances between node pairs, including hitting time, commute time, andpersonalized PageRank (PPR). Despite the potenti ..."
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coordinate spaces. We show that while existing graph coordinate systems (GCS) can accurately estimate shortest path distances, they produce significant errors when embedding random-walk distances. Based on our observations, we propose a new graph embedding system that explicitly accounts for per-node graph

Wandering domains and random walks in . . .

by Jean-pierre Marco, David Sauzin , 2003
"... We construct examples of Gevrey non-analytic perturbations of an integrable Hamiltonian system which give rise to an open set of unstable orbits and to a special kind of symbolic dynamics. We find an open ball in the phase space, which is transported by the Hamiltonian flow from − ∞ to + ∞ along o ..."
Abstract - Cited by 1 (0 self) - Add to MetaCart
one coordinate axis, at a speed that we estimate with respect to the size of the perturbation. Taking advantage of the hyperbolic features of this unstable system, particularly the splitting of invariant manifolds, we can also embed a random walk along this axis into the near-integrable dynamics.

Sampling from large matrices: an approach through geometric functional analysis

by Mark Rudelson, Roman Vershynin - Journal of the ACM , 2006
"... Abstract. We study random submatrices of a large matrix A. We show how to approximately compute A from its random submatrix of the smallest possible size O(r log r) with a small error in the spectral norm, where r = �A�2 F /�A�22 is the numerical rank of A. The numerical rank is always bounded by, a ..."
Abstract - Cited by 132 (5 self) - Add to MetaCart
Abstract. We study random submatrices of a large matrix A. We show how to approximately compute A from its random submatrix of the smallest possible size O(r log r) with a small error in the spectral norm, where r = �A�2 F /�A�22 is the numerical rank of A. The numerical rank is always bounded by

SPECTRAL ANALYSIS OF RANDOM WALK OPERATORS ON EUCLIDIAN SPACE

by Colin Guillarmou, Laurent Michel
"... Abstract. We study the operator associated to a random walk on R d endowed with a probability measure. We give a precise description of the spectrum of the operator near 1 and use it to estimate the total variation distance between the iterated kernel and its stationary measure. Our study contains t ..."
Abstract - Cited by 2 (2 self) - Add to MetaCart
Abstract. We study the operator associated to a random walk on R d endowed with a probability measure. We give a precise description of the spectrum of the operator near 1 and use it to estimate the total variation distance between the iterated kernel and its stationary measure. Our study contains

Tests for Random Walk Coefficients in State Space Models

by Martin Moryson , 1996
"... This paper deals with testing the constancy of coefficients in regression models against the alternative of following a random walk. Different small sample and asymptotic tests are compared on a Monte Carlo basis. It turns out that the easier to apply large sample tests perform almost as good as the ..."
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This paper deals with testing the constancy of coefficients in regression models against the alternative of following a random walk. Different small sample and asymptotic tests are compared on a Monte Carlo basis. It turns out that the easier to apply large sample tests perform almost as good

Measuring Index Quality using Random Walks on the Web

by Monika Henzinger Allan, Allan Heydon, Michael Mitzenmacher, Marc Najork - In Proceedings of the Eighth International World Wide Web Conference , 1999
"... Recent research has studied how to measure the size of a search engine, in terms of the number of pages indexed. In this paper, we consider a different measure for search engines, namely the quality of the pages in a search engine index. We provide a simple, effective algorithm for approximating t ..."
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the quality of an index by performing a random walk on the Web, and we use this methodology to compare the index quality of several major search engines.

Transition probability estimates for long range random walks

by Mathav Murugan, Laurent Saloff-coste
"... Abstract. Let (M,d, µ) be a uniformly discrete metric measure space satisfy-ing space homogeneous volume doubling condition. We consider discrete time Markov chains on M symmetric with respect to µ and whose one-step transition density is comparable to (Vh(d(x, y))φ(d(x, y)) −1, where φ is a positiv ..."
Abstract - Cited by 4 (2 self) - Add to MetaCart
Abstract. Let (M,d, µ) be a uniformly discrete metric measure space satisfy-ing space homogeneous volume doubling condition. We consider discrete time Markov chains on M symmetric with respect to µ and whose one-step transition density is comparable to (Vh(d(x, y))φ(d(x, y)) −1, where φ is a
Results 11 - 20 of 1,174