* Results in this paper, without any proofs, have been announced in an
extended abstract (Raghavan et al., 2018a), and fleshed out in the technical
report (Raghavan et al., 2018b [arXiv:1806.00543]). This manuscript covers a
subset of results from Raghavan et al. (2018a,b), focusing on the greedy
algorithm, and is streamlined accordingly Access Paper or Ask Questions