Search results for "Redundancy"
showing 10 items of 100 documents
Gaussianizing the Earth: Multidimensional Information Measures for Earth Data Analysis
2021
Information theory is an excellent framework for analyzing Earth system data because it allows us to characterize uncertainty and redundancy, and is universally interpretable. However, accurately estimating information content is challenging because spatio-temporal data is high-dimensional, heterogeneous and has non-linear characteristics. In this paper, we apply multivariate Gaussianization for probability density estimation which is robust to dimensionality, comes with statistical guarantees, and is easy to apply. In addition, this methodology allows us to estimate information-theoretic measures to characterize multivariate densities: information, entropy, total correlation, and mutual in…
Synergetic and redundant information flow detected by unnormalized Granger causality: application to resting state fMRI
2015
Objectives: We develop a framework for the analysis of synergy and redundancy in the pattern of information flow between subsystems of a complex network. Methods: The presence of redundancy and/or synergy in multivariate time series data renders difficult to estimate the neat flow of information from each driver variable to a given target. We show that adopting an unnormalized definition of Granger causality one may put in evidence redundant multiplets of variables influencing the target by maximizing the total Granger causality to a given target, over all the possible partitions of the set of driving variables. Consequently we introduce a pairwise index of synergy which is zero when two in…
Multiscale partial information decomposition of dynamic processes with short and long-range correlations: theory and application to cardiovascular co…
2022
Abstract Objective. In this work, an analytical framework for the multiscale analysis of multivariate Gaussian processes is presented, whereby the computation of Partial Information Decomposition measures is achieved accounting for the simultaneous presence of short-term dynamics and long-range correlations. Approach. We consider physiological time series mapping the activity of the cardiac, vascular and respiratory systems in the field of Network Physiology. In this context, the multiscale representation of transfer entropy within the network of interactions among Systolic arterial pressure (S), respiration (R) and heart period (H), as well as the decomposition into unique, redundant and s…
2D motif basis applied to the classification of digital images
2016
The classification of raw data often involves the problem of selecting the appropriate set of features to represent the input data. Different types of features can be extracted from the input dataset, but only some of them are actually relevant for the classification process. Since relevant features are often unknown in real-world problems, many candidate features are usually introduced. This degrades both the speed and the predictive accuracy of the classifier due to the presence of redundancy in the set of candidate features. Recently, a special class of bidimensional motifs, i.e. 2D motif basis has been introduced in the literature. 2D motif basis showed to be powerful in capturing the r…
The serine/threonine kinase 33 is present and expressed in palaeognath birds but has become a unitary pseudogene in neognaths about 100 million years…
2015
Background Serine/threonine kinase 33 (STK33) has been shown to be conserved across all major vertebrate classes including reptiles, mammals, amphibians and fish, suggesting its importance within vertebrates. It has been shown to phosphorylate vimentin and might play a role in spermatogenesis and organ ontogenesis. In this study we analyzed the genomic locus and expression of stk33 in the class Aves, using a combination of large scale next generation sequencing data analysis and traditional PCR. Results Within the subclass Palaeognathae we analyzed the white-throated tinamou (Tinamus guttatus), the African ostrich (Struthio camelus) and the emu (Dromaius novaehollandiae). For the African os…
On the Non-uniform Redundancy of Representations for Grammatical Evolution: The Influence of Grammars
2018
The representation used in grammatical evolution (GE) is non-uniformly redundant as some phenotypes are represented by more genotypes than others. This article studies how the non-uniform redundancy of the GE representation depends on various types of grammars. When constructing the phenotype tree from a genotype, the used grammar determines Bavg, the average branching factor. Bavg measures the expected number of non-terminals chosen when mapping one genotype codon to a phenotype tree node. First, the paper illustrates that the GE representation induces a bias towards small trees. This bias gets stronger with lower Bavg. For example, when using a grammar with Bavg = 0.5, 75% of all genotype…
Information Decomposition in Multivariate Systems: Definitions, Implementation and Application to Cardiovascular Networks
2016
The continuously growing framework of information dynamics encompasses a set of tools, rooted in information theory and statistical physics, which allow to quantify different aspects of the statistical structure of multivariate processes reflecting the temporal dynamics of complex networks. Building on the most recent developments in this field, this work designs a complete approach to dissect the information carried by the target of a network of multiple interacting systems into the new information produced by the system, the information stored in the system, and the information transferred to it from the other systems; information storage and transfer are then further decomposed into amou…
British-American Contrasts in the Use of the Past Perfect: Negotiating Ambiguity versus Redundancy?
2021
Abstract The present study provides an empirical analysis of British-American contrasts in the overall use of the past perfect as well as its functional distribution. Studies on variation according to national variety report a decline of the past perfect spearheaded by American English (cf. Elsness, J. 1997. The Perfect and Preterite in Contemporary and Earlier English (Topics in English Linguistics 21). Berlin: Mouton de Gruyte; Bowie, J., S. Wallis, and B. Aarts. 2013. “The Perfect in Spoken British English.” In The Verb Phrase in English. Investigating Recent Language Change with Corpora, edited by B. Aarts, J. Close, G. Leech, and S. Wallis, 318–52. Cambridge: Cambridge University Press…
Illusory conjunctions in French: The nature of sublexical units in visual word recognition
2005
The respective influence of orthographic redundancy (Seidenberg, 1987) and syllable boundaries (Rapp, 1992) on reading units in French was tested in three experiments, using the illusory conjunction paradigm (Prinzmetal, Treiman, & Rho, 1986). Bigram boundaries were defined according to bigram frequencies. The data showed that the syllable effect was attenuated or cancelled when syllable boundaries did not coincide with bigram boundaries. Reading units were defined by syllable and orthographic information. The implications of such findings for the dual route theory and the PDP model are discussed.
Optimal placement of 3D sensors considering range and field of view
2017
This paper describes a novel approach to the problem of optimal placement of 3D sensors in a specified volume of interest. The coverage area of the sensors is modelled as a cone having limited field of view and range. The volume of interest is divided into many, smaller cubes each having a set of associated Boolean and continuous variables. The proposed method could be easily extended to handle the case where certain sub-volumes must be covered by several sensors (redundancy), for example ex-zones, regions where humans are not allowed to enter or regions where machine movement may obstruct the view of a single sensor. The optimisation problem is formulated as a Mixed-Integer Linear Program …