We study the problem of producing a global ranking of items given pairwise ranking information, when the items to be ranked arrive in an online fashion. We study both the maximizat...
We prove that approximating the Max Acyclic Subgraph problem within a factor better than 1/2 is Unique-Games hard. Specifically, for every constant ε > 0 the following holds:...
We present a polynomial time approximation scheme (PTAS) for the minimum feedback arc set problem on tournaments. A simple weighted generalization gives a PTAS for KemenyYoung ran...