How Do Friendships Form?

  title={How Do Friendships Form?},
  author={Bruce I. Sacerdote and David Marmaros},
  journal={NBER Working Paper Series},
We examine how people form social networks among their peers. We use a unique dataset that tells us the volume of email between any two people in the sample. The data are from students and recent graduates of Dartmouth College. First year students interact with peers in their immediate proximity and form long term friendships with a subset of these people. This result is consistent with a model in which the expected value of interacting with an unknown person is low (making traveling solely to… 

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Peer Effects in Academic Outcomes: Evidence from a Natural Experiment

  • D. Zimmerman
  • Psychology
    Review of Economics and Statistics
  • 2003
I use data from Williams College to implement a quasi-experimental empirical strategy aimed at measuring peer effects in academic outcomes. In particular, I use data on individual students' grades,

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