Information Technology Reference
In-Depth Information
2.5.1.
The preparation of collections
The strategy of collecting information was elaborated by defining profiles
representative of the targeted population and the potential contexts of use.
2.5.1.1.
Population sample
The variability of the population was defined on the notion of a traveler. Socio-
demographic data provided markers for the profiles of network users. Criteria that
had an impact on motives, times and constraints of trips were taken into account. For
example, people that work have frequent home/work journeys with specific times;
people travelling for a leisure activity circulate more easily in the middle of the day;
and the elderly can have mobility difficulties.
Aspects that can modify the information that is sought have also been integrated.
For example, knowledge of the network conditions information needs in terms of
maps and meshing of the network; possible disabilities can require particular
modalities (e.g. for the visually impaired) or specific needs (e.g. points accessible to
wheelchairs). Students represent an important part of subscribers; people outside the
urban area have longer journeys with more connections.
The criteria that characterize the population (student, senior, active, with
knowledge of the network, etc.) have been used to build a sample of 36 people.
These profiles were combined to enrich the number of cases studied, for example:
active and season ticket holder, senior and stranger to the urban area, student in a
wheelchair and who does not know the urban area, etc. The sample was then
constructed to respect a representativeness of at least six people per criterion: six
external, six seniors, six active, etc. According to Nielsen [NIE 93] or Brangier and
Barcenilla [BRA 03], this number allows the collection of nearly 80% of needs for
the corresponding profiles.
2.5.1.2.
Sample of contexts
The experiment domain of the project was an urban area of average size: the
town of Orleans and the 22 surrounding communities, with a transport network
comprising a tramway line and around 30 bus lines. This agglomeration size enables
us to have an important variability of contexts.
The lines' timetable varies according to the function of the transport mode and
the sectors served. The tram line and certain bus lines have a high frequency and a
regular rhythm, but other lines have variable frequencies according to days or time
of day. The network proposes numerous connections. A few stations are very
important (12 lines at the center of the agglomeration in the Orleans station, eight
