1
$\begingroup$

Given parameters $\lambda, \nu>0$, a covariance matrix $R$, a mean vector $\mu \in R^p$, the Arellano-Valle and Bolfarine's generalized $t$ distribution is given by (see, for example, the book by Kotz and Nadarajah) \begin{equation} f(x)=\frac{\Gamma((\nu+p)/2)}{(\pi)^\frac{p}{2}\Gamma(\nu/2)|R|^\frac{1}{2}} \left[ 1+\frac{1}{\lambda}(x-\mu)^T R^{-1} (x-\mu) \right]^{-(\nu+p)/2}, \end{equation} where $x \in R^p$.

I want to find the expectation, under $f(x)$ of something similar to the density, i.e., I want to evaluate

\begin{equation} \int_x f(x) \left[ 1+\frac{1}{\lambda_2}(x-\mu_2)^T R_2^{-1} (x-\mu_2) \right]^{-\nu_2} dx, \end{equation} where $R_2$ is a covariance matrix, $\mu_2$ is a vector, and $\lambda_2>0$.

Is there a closed form expression for this integral for $x \in R^p$? In 1-d?

$\endgroup$

1 Answer 1

0
$\begingroup$

I am not sure a closed-form expression is known in the literature, but I found this paper that describes other properties of that integral without solving it.

$\endgroup$
1
  • $\begingroup$ The link to springerlink.com is broken. I'm also unable to find any snapshot saved on the Wayback Machine. $\endgroup$ Commented Apr 17, 2023 at 7:31

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .