We show that any point in the convex hull of each of (
d+1) sets of (
d+1) points in ℝ
d
is contained in at least
⌊(
d+2)
2/4
⌋ simplices with one vertex from each set.
Keywords Computational geometry - Carathéodory theorem - Colourful Carathéodory theorem - Simplicial depth - Colourful simplicial depth
Both authors were supported by NSERC Discovery grants. Additionally, T. Stephen was supported by DFG FG-468 and the Dynamical
Systems research focus at the University of Magdeburg.