Convex measure same thing as it being a logarithmically concave measure. The classes of "s"-convex measures form a nested increasing family as "s" decreases to −∞" or, equivalently Thus, the collection of −∞-convex measures is the largest such class, whereas the 0-convex measures (the logarithmically concave measures) are the smallest class. The convexity of a measure "μ" on "n"-dimensional Euclidean space R in the sense above is closely related to the convexity of its probability density function. Indeed, "μ" is "s"-convex if and only if there is an absolutely continuous measure "ν" with probability density function "ρ" on some R so that
Crepuscular rays Crepuscular rays Crepuscular rays (more commonly known as sunbeams, sun rays, splintered light, or god rays), in atmospheric optics, are rays of sunlight that appear to radiate from the point in the sky where the Sun is located. Shining through openings in clouds (particularly stratocumulus) or between other objects, these columns of sunlit particulates are separated by darker cloud-shadowed volumes. Despite seeming to converge toward the light source, the rays are in fact near-parallel shafts of sunlight. Their apparent convergence is a perspective effect. This phenomenon mimics the way parallel railway lines or long hallways, for example, seem to seek