  Due to their essential role as places for socialization, "third places" -
social places where people casually visit and communicate with friends and
neighbors - have been studied by a wide range of fields including network
science, sociology, geography, urban planning, and regional studies. However,
the lack of a large-scale census on third places kept researchers from
systematic investigations. Here we provide a systematic nationwide
investigation of third places and their social networks, by using Facebook
pages. Our analysis reveals a large degree of geographic heterogeneity in the
distribution of the types of third places, which is highly correlated with
baseline demographics and county characteristics. Certain types of pages like
"Places of Worship" demonstrate a large degree of clustering suggesting
community preference or potential complementarities to concentration. We also
found that the social networks of different types of social place differ in
important ways: The social networks of 'Restaurants' and 'Indoor Recreation'
pages are more likely to be tight-knit communities of pre-existing friendships
whereas 'Places of Worship' and 'Community Amenities' page categories are more
likely to bridge new friendship ties. We believe that this study can serve as
an important milestone for future studies on the systematic comparative study
of social spaces and their social relationships.
