abstract: Decades of research in cyberpsychology and human-computer interaction has pointed to a strong distinction between the online and offline worlds, suggesting that attitudes and behaviors in one domain do not necessarily generalize to the other. However, as humans spend increasing amounts of time in the digital world, psychological understandings of safety may begin to influence human perceptions of threat while online. This dissertation therefore examines whether perceived threat generalizes between domains across archival, correlational, and experimental research methods. Four studies offer insight into the relationship between objective indicators of physical and online safety on the levels of nation and state; the relationship between perceptions of these forms of safety on the individual level; and whether experimental manipulations of one form of threat influence perceptions of threat in the opposite domain. In addition, this work explores the impact of threat perception-related personal and situational factors, as well as the impact of threat type (i.e., self-protection, resource), on this hypothesized relationship. Collectively, these studies evince a positive relationship between physical and online safety in macro-level actuality and individual-level perception. Among individuals, objective indicators of community safety—as measured by zip code crime data—were a positive reflection of perceptions of physical safety; these perceptions, in turn, mapped onto perceived online safety. The generalization between perceived physical threat and online threat was stronger after being exposed to self-protection threat manipulations, possibly underscoring the more dire nature of threats to bodily safety than those to valuable resources. Most notably, experimental findings suggest that it is not the physical that informs the digital, but rather the opposite: Online threats blur more readily into physical domains, possibly speaking to the concern that dangers specific to the digital world will bleed into the physical one. This generalization of threat may function as a strategy to prepare oneself for future dangers wherever they might appear; and indeed, perceived threat in either world positively influenced desires to act on recommended safety practices. Taken together, this research suggests that in the realm of threat perception, the boundaries between physical and digital are less rigid than may have been previously believed. / Dissertation/Thesis / Doctoral Dissertation Psychology 2017