“We are never right, we can only be sure we are wrong”

Consider a set system, a.k.a. hypergraph, where is the ground set and where . We wish to color the ground set $V$ with two colors, say red and blue, in such way that all sets in the family are colored in a  “balanced” way, i.e., each set has nearly the same number of red and blue points. […]

Consider picking a graph with m edges on n vertices uniformly at random from the set of all graphs with n vertices and m edges. What is the expected number of triangles? Before we give an exact formula, consider the following heuristic. We can approximate this graph with a random binomial graph (each edge appears […]