@article{generalizedoptimalmatchingmethodsfor,
  title = {Generalized Optimal Matching Methods for Causal Inference},
  author = {Nathan Kallus},
  year = {2016},
  eprint = {1612.08321},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1612.08321v3},
}