Sharp Concentration of Hitting Size for Random Set Systems
  Consider the random set system of {1,2,...,n}, where each subset in the power set is chosen independently with probability p. A set H is said to be a hitting set if it intersects each chosen set. The second moment method is used to exhibit the sharp concentration of the minimal size of H for a variety of values of p. 
Jessie Deering, Anant Godbole, William Jamieson, and Lucia Petito
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