Covariance in probability theory and statistics is a measure of the joint variability of two random variables. The sign of the covariance, therefore,...
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and statistics, a covariance matrix (also known as auto-covariance matrix, dispersion matrix, variance matrix, or variance–covariance matrix) is a square...
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Look up covariance or contravariance in Wiktionary, the free dictionary. Covariance and contravariance may refer to: Covariance and contravariance of...
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average) or empirical mean (empirical average), and the sample covariance or empirical covariance are statistics computed from a sample of data on one or more...
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through space". Lorentz covariance, a related concept, is a property of the underlying spacetime manifold. Lorentz covariance has two distinct, but closely...
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In theoretical physics, general covariance, also known as diffeomorphism covariance or general invariance, consists of the invariance of the form of physical...
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together, and may refer to: Covariance matrix, a matrix of covariances between a number of variables Covariance or cross-covariance between two random variables...
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statistics, sometimes the covariance matrix of a multivariate random variable is not known but has to be estimated. Estimation of covariance matrices then deals...
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theory and statistics, the covariance function describes how much two random variables change together (their covariance) with varying spatial or temporal...
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Principal component analysis (section Covariances)
eigenvectors of the data's covariance matrix. Thus, the principal components are often computed by eigendecomposition of the data covariance matrix or singular...
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In probability theory and statistics, the mathematical concepts of covariance and correlation are very similar. Both describe the degree to which two random...
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" Regardless of Gaussianity, however, if the process and measurement covariances are known, then the Kalman filter is the best possible linear estimator...
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Analysis of covariance (ANCOVA) is a general linear model that blends ANOVA and regression. ANCOVA evaluates whether the means of a dependent variable...
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the covariance of two variables and the product of their standard deviations; thus, it is essentially a normalized measurement of the covariance, such...
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product ⟨ ⋅ , ⋅ ⟩ {\displaystyle \langle \cdot ,\cdot \rangle } , the covariance of P is the bilinear form Cov: H × H → R given by C o v ( x , y ) = ∫...
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In statistics, the Matérn covariance, also called the Matérn kernel, is a covariance function used in spatial statistics, geostatistics, machine learning...
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{\displaystyle \left\{Y_{t}\right\}} , the cross-covariance is a function that gives the covariance of one process with the other at pairs of time points...
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In physics, a covariance group is a group of coordinate transformations between frames of reference (see for example Ryckman (2005)). A frame of reference...
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CMA-ES (redirect from Covariance matrix adaptation)
Covariance matrix adaptation evolution strategy (CMA-ES) is a particular kind of strategy for numerical optimization. Evolution strategies (ES) are stochastic...
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In physics, the principle of covariance emphasizes the formulation of physical laws using only those physical quantities the measurements of which the...
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The eddy covariance (also known as eddy correlation and eddy flux) is a key atmospheric measurement technique to measure and calculate vertical turbulent...
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Gaussian process (section Covariance functions)
then we might choose a rougher covariance function. Extreme examples of the behaviour is the Ornstein–Uhlenbeck covariance function and the squared exponential...
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Distance correlation (redirect from Distance covariance)
statistics and in probability theory, distance correlation or distance covariance is a measure of dependence between two paired random vectors of arbitrary...
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\operatorname {E} [X_{k}])^{\mathrm {T} },} and k × k {\displaystyle k\times k} covariance matrix Σ i , j = E [ ( X i − μ i ) ( X j − μ j ) ] = Cov [ X i , X...
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Covariance intersection (CI) is an algorithm for combining two or more estimates of state variables in a Kalman filter when the correlation between them...
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Autocovariance (redirect from Auto covariance)
a stochastic process, the autocovariance is a function that gives the covariance of the process with itself at pairs of time points. Autocovariance is...
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In probability theory, the law of total covariance, covariance decomposition formula, or conditional covariance formula states that if X, Y, and Z are...
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probability theory and statistics, a cross-covariance matrix is a matrix whose element in the i, j position is the covariance between the i-th element of a random...
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In physics, especially in multilinear algebra and tensor analysis, covariance and contravariance describe how the quantitative description of certain geometric...
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average value. It is the second central moment of a distribution, and the covariance of the random variable with itself, and it is often represented by σ 2...
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