Centerpoint Theorems for Wedges

The Centerpoint Theorem states that, for any set S of n points in R, there exists a point p in R such that every closed halfspace containing p contains at least dn/(d+ 1)e points of S. We consider generalizations of the Centerpoint Theorem in which halfspaces are replaced with wedges (cones) of angle α. In R, we give bounds that are tight for all values of α and give an O(n) time algorithm to find a point satisfying these bounds. We also give partial results for R and, more generally, R.