.. |newpage| raw:: latex \newpage .. |cr| raw:: latex \hspace{0.0mm} .. _rst_dist_mcp_overview: Overview and literature ------------------------------------------------------------------------------- See also: :cite:t:`Hahn1971`, :cite:t:`Narula1978`, :cite:t:`Stoline1979`, :cite:t:`Tong1990`, :cite:t:`Genz2020`. See also: :cite:t:`Bechhofer1988` See also: :cite:t:`Genz2009` See also: :cite:t:`Genz2020` See also: :cite:t:`Hahn1971` See also: :cite:t:`Narula1978` See also: :cite:t:`Stoline1979` See also: :cite:t:`Tong1990` For tables see :cite:t:`Soong2001`. For tables see :cite:t:`David1953`. For tables see :cite:t:`David1972`. An `n`-dimensional random variable `\textbf{X}` with mean vector `\boldsymbol{\mu}` and covariance matrix `\boldsymbol{\Sigma}` is said to have a nonsingular multivariate normal distribution, in symbols `\boldsymbol{X} \sim \mathcal{N}_n(\boldsymbol{\mu}, \boldsymbol{\Sigma})`, if `\boldsymbol{\Sigma}` is positive definite, and the density function of `\textbf{X}` is of the form (see Tong 1990): .. math:: f(\boldsymbol{x; \mu, \Sigma}) = \frac{1}{(2\pi)^{n/2} \vert \boldsymbol{\Sigma} \vert ^{1/2}} e^{-Q_n(\boldsymbol{x; \mu, \Sigma})/2}, \quad \boldsymbol{x} \in \Re^n where .. math:: Q_n(\boldsymbol{x; \mu, \Sigma}) = (\boldsymbol{x - \mu})' \boldsymbol{\Sigma^{-1}} (\boldsymbol{x - \mu}). The notion of cumulative distribution function (cdf) in one dimension can be extended to the multidimensional case, based on rectangular regions. We define the cdf `F(\mathbf {x} )` of a random vector `\mathbf {X}` as the probability that all components `\mathbf {X}` are less than or equal to the corresponding values in the vector `\mathbf {x}`: .. math:: F(\mathbf {x} )=\mathbb {P} (\mathbf {X} \leq \mathbf {x} ),\quad {\text{where }}\mathbf {X} \sim {\mathcal {N}}({\boldsymbol {\mu }},\,{\boldsymbol {\Sigma }}). See also: Genz(2009), Bretz(2003). Let `\boldsymbol{R} = (\rho_{ij})` be an `n \times n` symmetric matrix such that it is either positive definite or positive semidefinite and `\rho_{ii} = 1 (i=1,\ldots,n)`. Let `\textbf{Z} = (Z_1,\ldots,Z_{n})'` have an `\mathcal{N}_n(\boldsymbol{0}, \boldsymbol{R})` distribution, and let the univariate variable `S` be such that `S` is independent of `\boldsymbol{Z}`, and `\nu S^2` has a `\chi^2(\nu)` distribution. Then a natural generalization of the Student's `t` variable is .. math:: \boldsymbol{t} = (t_1,\ldots,t_n)' = \left(\frac{Z_1}{S},\ldots,\frac{Z_n}{S}\right)' . If `\boldsymbol{R}` is positive definite, then the density of `\boldsymbol{t}` (with correlation matrix `\boldsymbol{R}` and degrees of freedom `\nu`) is given by \citep{Tong_1990}: .. math:: h(\boldsymbol{t; R}, \nu)= \frac{\Gamma((n+\nu)/2)}{(\nu \pi)^{n/2} \Gamma(\nu/2) \vert \boldsymbol{R} \vert^{1/2}} \left(1+\frac{1}{\nu} \boldsymbol{t}' \boldsymbol{R}^{-1} \boldsymbol{t} \right)^{-(n+\nu)/2} , \quad \boldsymbol{t} \in \Re^n. The notion of cumulative distribution function (cdf) in one dimension can be extended to the multidimensional case, based on rectangular regions. We define the cdf `F(\mathbf {x} )` of a random vector `\mathbf {X}` as the probability that all components `\mathbf {X}` are less than or equal to the corresponding values in the vector `\mathbf {x}`: .. math:: F(\mathbf {x} )=\mathbb {P} (\mathbf {X} \leq \mathbf {x} ),\quad {\text{where }}\mathbf {X} \sim {\mathcal {N}}({\boldsymbol {\mu }},\,{\boldsymbol {\Sigma }}). See also: Genz(2009), Bretz(2003).