In statistics, the Wishart distribution is a generalization to multiple dimensions of the chi-squared distribution, or, in the case of non-integer degrees of freedom, of the gamma distribution. It is named in honor of John Wishart, who first formulated the distribution in 1928.
It is any of a family of probability distributions defined over symmetric, nonnegative-definite matrix-valued random variables (“random matrices”). These distributions are of great importance in the estimation of covariance matrices in multivariate statistics. In Bayesian statistics, the Wishart distribution is the conjugate prior of the inverse covariance-matrix of a multivariate-normal random-vector.
Read more about Wishart Distribution: Definition, Occurrence, Probability Density Function, Theorem, Estimator of The Multivariate Normal Distribution, Bartlett Decomposition, The Possible Range of The Shape Parameter, Relationships To Other Distributions
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