Geoscience Reference
In-Depth Information
of the attraction is the share of the labour force living in a place and working at the
center. The most used threshold for this share in the literature concerning the
definition of European urban areas is 10%. This threshold, unlike the former, has no
generic character to the extent that it depends on the mesh in which the information
on commuters is captured. Therefore, this threshold appears in the form of parameter
in the model domain, and its possible values are studied in the empirical domain.
The objects constructed following this approach are of the
fiat
type. The
specifications of the whole process that leads from story to measurement must be
explicit in order to verify its consistency.
Figure 1.3.
From the conceptual object to its measurement: three steps
1.2. Locating spatial objects in time
The basic concepts to apprehend the spatial objects of interest being defined, the
question is about situating these objects in time. The challenge is to consider them in
their full spatio-temporal dimension, by focusing on their evolution as well as on the
processes leading to their transformation. In a parallel way to the approach adopted
in the first part of this chapter, we will proceed in two stages, first examining the
point of view of the philosophers, and then that of the geomaticians, in order to
benefit from the additional insight of these two approaches.
