Random convex hulls: a variance revisited (with S. Finch).
Advances in Applied Probability, 36, 981-986 (2004)

An exact expression is determined for the asymptotic constant c₂ in the limit theoreom of Groeneboom (1988) which states that the number of vertices of the convex hull of a uniform sample of n random points from a circular disk satisfies a central limit theorem as n tends to infinity with asymptotic variance 2 \pi c₂ n^1/3.