Bekker, Andriette, 1958-Roux, Jacobus J.J.Arashi, Mohammad2011-10-032011-10-032011-12Bekker, A, Roux, JJJ & Arashi,M 2011, 'Wishart ratios with dependent structure : new members of the bimatrix beta type IV', Linear Algebra and its Applications, vol. 435, no. 12, pp. 3243-3260, doi: 10.1016/j.laa.2011.06.007. [http://www.elsevier.com/locate/]0024-3795 (print)1873-1856 (online)10.1016/j.laa.2011.06.007http://hdl.handle.net/2263/17387In multivariate statistics under normality, the problems of interest are random covariance matrices (known as Wishart matrices) and "ratios" of Wishart matrices that arise in multivariate analysis of variance (MANOVA). The bimatrix variate beta type IV distribution (also known in the literature as bimatrix variate generalised beta; matrix variate generalization of a bivariate beta type I) arises from "ratios" of Wishart matrices. In this paper, we add a further independent Wishart random variate to the "denominator" of one of the ratios; this results in deriving the exact expression for the density function of the bimatrix variate extended beta type IV distribution. The latter leads to the proposal of the bimatrix variate extended F distribution. Some interesting characteristics of these newly introduced bimatrix distributions are explored. Lastly, we focus on the bivariate variate extended beta type IV distribution (that is an extension of bivariate Jones’ beta).en© 2011 Elsevier Inc. All rights reserved.Bimatrix variate beta type IV distributionBimatrix variate Kummer extended beta type IV distributionGeneralized Laguerre polynomialHypergeometric function of matrix argumentInvariant polynomialsWishart matricesMeijer’s G-functionMoment generating functionStress-strengthLaplace transformationWishart ratios with dependent structure : new members of the bimatrix beta type IVPostprint Article