One might think that online social media, operating on a global scale via the Internet, wouldn't be affected much by geography. In fact, authors Emilio Ferrara, Onur Varol, Fil Menczer, and Sandro Flammini, show in their paper Traveling trends: social butterflies or frequent fliers? that online social media trends follow similar patterns as epidemics and disease patterns, exploiting the same pathways as human travelers to diffuse across the country.
The research identified three distinct geographical clusters in the US information flow (east coast, midwest, and southwest)
as well as global patterns in the flow corresponding to main air traffic hubs. They conclude that travel hubs act as trendsetters, generating topics that eventually trend at the country level, then driving the conversation across the country. This work has received press attention from sources including Washington Post and Seattle Times.