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327
Integrating topological and metric maps for mobile robot navigation: A statistical approach
 In Proceedings of the AAAI Fifteenth National Conference on Artificial Intelligence
, 1998
"... The problem of concurrent mapping and localization has received considerable attention in the mobile robotics community. Existing approaches can largely be grouped into two distinct paradigms: topological and metric. This paper proposes a method that integrates both. It poses the mapping problem as ..."
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Cited by 68 (13 self)
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The problem of concurrent mapping and localization has received considerable attention in the mobile robotics community. Existing approaches can largely be grouped into two distinct paradigms: topological and metric. This paper proposes a method that integrates both. It poses the mapping problem as a statistical maximum likelihood problem, and devises an efficient algorithm for search in likelihood space. It presents an novel mapping algorithm that integrates two phases: a topological and a metric mapping phase. The topological mapping phase solves a global position alignment problem between potentially indistinguishable, significant places. The subsequent metric mapping phase produces a finegrained metric map of the environment in floatingpoint resolution. The approach is demonstrated empirically to scale up to large, cyclic, and highly ambiguous environments.
A tutorial introduction to the minimum description length principle
 in Advances in Minimum Description Length: Theory and Applications. 2005
"... ..."
Integrating structured biological data by kernel maximum mean discrepancy
 IN ISMB
, 2006
"... Motivation: Many problems in data integration in bioinformatics can be posed as one common question: Are two sets of observations generated by the same distribution? We propose a kernelbased statistical test for this problem, based on the fact that two distributions are different if and only if the ..."
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Cited by 54 (15 self)
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Motivation: Many problems in data integration in bioinformatics can be posed as one common question: Are two sets of observations generated by the same distribution? We propose a kernelbased statistical test for this problem, based on the fact that two distributions are different if and only if there exists at least one function having different expectation on the two distributions. Consequently we use the maximum discrepancy between function means as the basis of a test statistic. The Maximum Mean Discrepancy (MMD) can take advantage of the kernel trick, which allows us to apply it not only to vectors, but strings, sequences, graphs, and other common structured data types arising in molecular biology. Results: We study the practical feasibility of an MMDbased test on three central data integration tasks: Testing crossplatform comparability of microarray data, cancer diagnosis, and datacontent based schema matching for two different protein function classification schemas. In all of these experiments, including highdimensional ones, MMD is very accurate in finding samples that were generated from the same distribution, and outperforms its best competitors. Conclusions: We have defined a novel statistical test of whether two samples are from the same distribution, compatible with both multivariate and structured data, that is fast, easy to implement, and works well, as confirmed by our experiments.
Interpretation Of Rank Histograms For Verifying Ensemble Forecasts
, 2000
"... Rank histograms are a tool for evaluating ensemble forecasts. They are useful for determining the reliability of ensemble forecasts and for diagnosing errors in its mean and spread. Rank histograms are generated by repeatedly tallying the rank of the verification (usually, an observation) relative t ..."
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Cited by 49 (5 self)
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Rank histograms are a tool for evaluating ensemble forecasts. They are useful for determining the reliability of ensemble forecasts and for diagnosing errors in its mean and spread. Rank histograms are generated by repeatedly tallying the rank of the verification (usually, an observation) relative to values from an ensemble sorted from lowest to highest. However, an uncritical use of the rank histogram can lead to misinterpretations of the qualities of that ensemble. For example, a flat rank histogram, ususally taken as a sign of reliability, can still be generated from unreliable ensembles. Similarly, a Ushaped rank histogram, commonly understood as indicating a lack of variability in the ensemble, can also be a sign of conditional bias. It is also shown that flat rank histograms can be generated for some model variables if the variance of the ensemble is correctly specified, yet if covariances between model grid points are improperly specified, rank histograms for combinations of mo...
Output MAI Distributions of Linear MMSE Multiuser Receivers in DSCDMA Systems
 IEEE TRANS. INFORM. THEORY
, 2001
"... Multipleaccess interference (MAI) in a codedivision multipleaccess (CDMA) system plays an important role in performance analysis and characterization of fundamental system limits. In this paper, we study the behavior of the output MAI of the minimum meansquare error (MMSE) receiver employed in t ..."
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Cited by 48 (8 self)
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Multipleaccess interference (MAI) in a codedivision multipleaccess (CDMA) system plays an important role in performance analysis and characterization of fundamental system limits. In this paper, we study the behavior of the output MAI of the minimum meansquare error (MMSE) receiver employed in the uplink of a directsequence (DS)CDMA system. We focus on imperfect powercontrolled systems with random spreading, and establish that in a synchronous system 1) the output MAI of the MMSE receiver is asymptotically Gaussian, and 2) for almost every realization of the signatures and received powers, the conditional distribution of the output MAI converges weakly to the same Gaussian distribution as in the unconditional case. We also extend our study to asynchronous systems and establish the Gaussian nature of the output interference. These results indicate that in a large system the output interference is approximately Gaussian, and the performance of the MMSE receiver is robust to the randomness of the signatures and received powers. The Gaussianity justifies the use of singleuser Gaussian codes for CDMA systems with linear MMSE receivers, and implies that from the viewpoints of detection and channel capacity, signaltointerference ratio (SIR) is the key parameter that governs the performance of the MMSE receiver in a CDMA system.
ExperienceDependent Integration of Texture and Motion Cues to Depth
, 1999
"... Previous investigators have shown that observers' visual cue combination strategies are remarkably flexible in the sense that these strategies adapt on the basis of the estimated reliabilities of the visual cues. However, these researchers have not addressed how observers' acquire these estimated re ..."
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Cited by 44 (3 self)
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Previous investigators have shown that observers' visual cue combination strategies are remarkably flexible in the sense that these strategies adapt on the basis of the estimated reliabilities of the visual cues. However, these researchers have not addressed how observers' acquire these estimated reliabilities. This article studies observers' abilities to learn cue combination strategies. Subjects made depth judgments about simulated cylinders whose shapes were indicated by motion and texture cues. Because the two cues could indicate different shapes, it was possible to design tasks in which one cue provided useful information for making depth judgments, whereas the other cue was irrelevant. The results of experiment 1 suggest that observers' cue combination strategies are adaptable as a function of training; subjects adjusted their cue combination rules to use a cue more heavily when the cue was informative on a task versus when the cue was irrelevant. Experiment 2 demonstrated that experiencedependent adaptation of cue combination rules is contextsensitive. On trials with presentations of short cylinders, one cue was informative, whereas on trials with presentations of tall cylinders, the other cue was informative. The results suggest that observers can learn multiple cue combination rules, and can learn to apply each rule in the appropriate context. Experiment 3 demonstrated a possible limitation on the contextsensitivity of adaptation of cue combination rules. One cue was informative on trials with presentations of cylinders at a left oblique orientation, whereas the other cue was informative on trials with presentations of cylinders at a right oblique orientation. The results indicate that observers did not learn to use different cue combination rules in differe...
A Subjective Metric of Authentication
 Proceedings of ESORICS'98, LouvainlaNeuve
, 1998
"... . Determining the authenticity of public keys in largescale open networks can not be based on certificates alone, but must also include the binding between the key used for certification and it's owner, as well as the trust relationships between individual agents. This paper describes a method for ..."
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Cited by 43 (4 self)
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. Determining the authenticity of public keys in largescale open networks can not be based on certificates alone, but must also include the binding between the key used for certification and it's owner, as well as the trust relationships between individual agents. This paper describes a method for computing authenticity measures based on certificates, on key binding, and on trust relationships. Two essential elements of the method are the opinion model which is a radically new way of representing trust, and subjective logic which consists of a set of logical operators for combining opinions. We show that our method for computing authenticity measures can be applied to both anarchic and hierarchic authentication networks. 1 Introduction Public key cryptography seems to be the technical solution for securing global open telecommunication networks. The problem however is to find a reliable way of determining the authenticity of public keys in a largescale open network. For this purpose...
RegisterTransfer Level Estimation Techniques for Switching Activity and Power Consumption
 in Proc. Int. Conf. ComputerAided Design
, 1996
"... We present techniques for estimating switching activity and power consumption in registertransfer level (RTL) circuits. Previous work on this topic has ignored the presence of glitching activity at various data path and control signals, which can lead to significant underestimation of switching act ..."
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Cited by 43 (3 self)
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We present techniques for estimating switching activity and power consumption in registertransfer level (RTL) circuits. Previous work on this topic has ignored the presence of glitching activity at various data path and control signals, which can lead to significant underestimation of switching activity. For data path blocks that operate on wordlevel data, we construct piecewise linear models that capture the variation of output glitching activity and power consumptionwith various wordlevel parameters like mean, standard deviation, spatial and temporal correlations, and glitching activity at the block's inputs. For RTL blocks that operate on data that need not have an associated wordlevel value, we present accurate bitlevel modeling techniques for glitching activity as well as power consumption. This allows us to perform accurate power estimation for controlflow intensive circuits, where most of the power consumed is dissipated in nonarithmetic components like multiplexers, regi...
Multicast Session Membership Size Estimation
 In Proc. of IEEE Infocom ’99
, 1999
"... We derive estimators and bounds that drive probabilistic polling algorithms for the estimation of the session size, r, of any potentially large scale multicast session. We base our analysis upon a mapping of polling mechanisms to the problem of estimating the parameter r of the binomial (r, p) distr ..."
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Cited by 42 (1 self)
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We derive estimators and bounds that drive probabilistic polling algorithms for the estimation of the session size, r, of any potentially large scale multicast session. We base our analysis upon a mapping of polling mechanisms to the problem of estimating the parameter r of the binomial (r, p) distribution. From the binomial model, we derive an inter val estimator for r, and we characterize the tradeoff between the estimator 's quality and its overhead in a manner readily matched to application requirements. We derive other estimators and bounds that enable applications to treat as a tunable parameter the confidence that they will not exceed their overhead limits. We also suggest revised estimators and other improvements for the mechanisms proposed by Bolot, Turletti, and Wakeman [1], and Nonnenmacher and Biersack [2], [3], [4].
A kernel method for the two sample problem
 ADVANCES IN NEURAL INFORMATION PROCESSING SYSTEMS 19
, 2007
"... We propose a framework for analyzing and comparing distributions, allowing us to design statistical tests to determine if two samples are drawn from different distributions. Our test statistic is the largest difference in expectations over functions in the unit ball of a reproducing kernel Hilbert ..."
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Cited by 40 (14 self)
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We propose a framework for analyzing and comparing distributions, allowing us to design statistical tests to determine if two samples are drawn from different distributions. Our test statistic is the largest difference in expectations over functions in the unit ball of a reproducing kernel Hilbert space (RKHS). We present two tests based on large deviation bounds for the test statistic, while a third is based on the asymptotic distribution of this statistic. The test statistic can be computed in quadratic time, although efficient linear time approximations are available. Several classical metrics on distributions are recovered when the function space used to compute the difference in expectations is allowed to be more general (eg. a Banach space). We apply our twosample tests to a variety of problems, including attribute matching for databases using the Hungarian marriage method, where they perform strongly. Excellent performance is also obtained when comparing distributions over graphs, for which these are the first such tests.