Database Reference
In-Depth Information
Figure 16.3 Conceptual model of CGI. The shaded concepts represent where the spa-
tial information could be retrieved. The SpatialLocation concept represents the physical
extension of the entities in the real world (person, device, and feature of interest).
a GPS device. The geographic information contained in the different levels may
be synchronized and coincident. To summarize and answer the first question in
the introduction, spatial location associated with a feature of interest or a person
in the real world may have a representation in the geo-social network, very often
associated to content as metadata.
16.4.2 Comparison among GPS, GSM, and Online Geo-Social
Network Data
In the last few years, many researchers studied geo-tagged data such as GPS
traces, GSMdata, and data coming fromgeo-social networks. These data coming
from GSM and GPS sources look different, and may seem not even comparable
with the geo-tagged data present in online social networks. However, we believe
that it is useful to the reader to highlight and compare some aspects. Therefore,
the purpose of this section is to shed some light on differences and similarities,
in both the data sources and the final tasks of analysis that can be performed on
them. Let us first review the different kinds of data that we refer to. Our first
