UC San Diego

Most social science theories attempt to explain the ways in which social interactions affect human behavior. Inferences therefore depend upon a researchers' ability to measure and characterize these interactions. In this dissertation, we highlight several inferential challenges in measuring social interactions and show how geographical data can be used to address them. One such challenge is posed by exposure to various treatments; many treatment variables of interest are difficult to measure in a coherent and unified way. Chapter 2 illustrates the way in which public records can be used to overcome this challenge. Another challenge is post-treatment sorting. Once social conflict begins, one of the first things that groups do is segregate themselves into smaller sub -groups. Chapter 3 introduces a new instrumental variable to correct for this bias in census data. Lastly, Chapter 4 introduces a novel method for estimating where social media users spend time during their day. These findings and novel methods will contribute to social scientists’ ability to study contextual effects on behavior.