Location-based social networks (LBSNs) have recently attracted the interest of millions of users who can now not only connect and interact with their friends--as it also happens in traditional online social networks--but can also voluntarily share their whereabouts in real time. A location database is the backbone of a location-based social network and includes fine-grained semantic information for real-world places. The footprints captured in a location database represent the socioeconomic activities of city dwellers and urban mobility at scale. LBSNs bridge the gap between the online and offine physical world, providing an unprecedented opportunity for researchers to access information that will allow them to place and understand human movements in the contexts of urban, social and economic activities. In this dissertation, I design statistical analysis and modeling frameworks to examine how factors, including social interaction, economic incentives and local events, affect human movement across places in urban space. The dissertation first shows that people's visitation to local places exhibit significant levels of homophily, where peer in uence can explain up to 40% of a geographically localized similarity between friends. We also find that the social selection mechanism is triggered by non-trivial similarity which is captured by places with specific network characteristics. Next, our quasi-experimental analysis reveals that online promotions in LBSNs are not as effective as anecdotal stories might suggest in attracting customers, and consequently in affecting the underlying city-dweller mobility. These results can have significant implications on advertisement strategies for local businesses. Finally, our developed framework is applied to assess the impact of local government decisions on urban mobility and economic activities, which can provide a blueprint for future educated policy making. The outcome of this dissertation is envisioned to help better understand human urban movements motivated by social, economic and external environmental factors and further foster applications in sociology, local economy and urban planning. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]