@Misc{matchit.paper,
  author = {Daniel Ho and Kosuke Imai and Gary King and Elizabeth Stuart},
  title = {Matching as Nonparametric Preprocessing for Parametric Causal Inference},
  year = {2005},
  url = {http://gking.harvard.edu/files/matchp.pdf}
}

@Manual{matchit.pkg,
    title = {MatchIt: Nonparametric Preprocessing for Parametric Casual
Inference},
    author = {Daniel Ho and Kosuke Imai and Gary King and Elizabeth Stuart},
    year = {2005},
    note = {R package version 2.2-5},
    url = {http://gking.harvard.edu/matchit},
  }

@Misc{burns2004,
  author = {Patrick Burns},
  title = {Performance Measurement via Random Portfolios},
  year = {2004},
  url = {http://www.burns-stat.com/pages/Working/perfmeasrandport.pdf}
}

@Article{rubin,
  author =       {Donald B. Rubin},
  title =        {Estimating Causal Effects of Treatments in Randomized and
Nonrandomized Studies},
  journal =      {Journal of Educational Psychology},
  year =         {1974},
  volume =       {66},
  pages =        {688--701}
}
