We investigate various properties of the sublevel set {x : g(x) ≤ 1} and the integration of h on this sublevel set when g and h are positively homogeneous functions. For instance, the latter integral reduces to integrating h exp(−g) on the whole space R n (a non Gaussian integral) and when g is a polynomial, then the volume of the sublevel set is a convex function of the coefficients of g. In fact, whenever h is nonnegative, the functional φ(g(x))h(x)dx is a convex function of g for a large class of functions φ : R+ → R. We also provide a numerical approximation scheme to compute the volume or integrate h (or, equivalently to approximate the associated non Gaussian integral). We also show that finding the sublevel set {x : g(x) ≤ 1} of minimum volume that contains some given subset K is a (hard) convex optimization problem for which we also propose two convergent numerical schemes. Finally, we provide a Gaussian-like property of non Gaussian integrals for homogeneous polynomials that are sums of squares and critical points of a specific function.1991 Mathematics Subject Classification. 26B15 65K10 90C22 90C25.