Data Collection for Understanding Urban Goods Movement - Sustainable Urban Logistics: Concepts, Methods and Information Systems - page 77

• Area specific surveys, which focus on a geographical area and are in general
very descriptive. The main examples of such category of surveys are roadside
interviews, parking observations and traffic counts, this last approach used in
conjunction with the above techniques to give complementary information.
The general survey techniques are the most complete (and complex) data
collection method: they provide broad but detailed data on the freight activity in
cities and sometimes even beyond the urban area (i.e. the US commodity flow
surveys). Every type of data (in the above typology) is collected during these
surveys, except for the external elements (category 4). These general surveys are
however the most expensive as it gathers fair amounts of resources (human and
material) to survey the entire supply-chain related to urban goods movements. The
inconvenient of this type of global survey is usually the lack of accuracy on urban
freight operations: for example KID, and MID, commodity flow survey are not
focused on the urban area but are national surveys (BESTUFS 2003 ). It is also
difficult to generate the interest of the stakeholders in participating in such surveys
if they are not statutory: the involvement of all the participants is a key in building
substantial data. New approaches such as the French surveys on the urban goods
movements are specifically designed for the urban area and therefore the most
suitable to understand freight flows and their formation in the urban area (Patier
and Routhier 2009 ).
Stakeholder surveys are related to the previous category as they can in fact be
parts of general surveys. They provide understanding of the organization of
transport and freight operations in the urban environment. As each stakeholder
represents a part of the supply-chain, surveying one or the other stakeholder will
give different (in quantity and quality) valuable information. The shippers and
establishments surveys provide more information on shipment and handling
operations, whereas freight operators and service provider surveys generate more
information on the activity of carriers and vehicle operations, while still providing
data on shipment and handling operation (maybe with lesser quality and quantity).
This survey type requires substantial resources if carried out thoroughly on a large
scale, but is very accurate. Again, as in the previous category, the involvement of
the surveyed stakeholders presents an additional difficulty, but is fundamental if
the goal is to build substantial sets of data.
The vehicles surveys can provide valuable information on the fleets, the
characteristics, and journey details of the vehicle. It mainly concerns the
''behaviours'' of the vehicles and fleets in the urban area. While the collected data
mainly concern the category 3 of the typology, it is also possible to gather precious
information in the first and second categories, depending on whether it is a driver
survey (which can give us information on pick-up/delivery operations and ship-
ment) or a GPS survey that can only provide the path taken, but with an extreme
accuracy on speeds, accelerations and routes (Pluvinet et al. 2012 ). Again the
importance of communication with the actors of the urban freight transport is
critical to the success of these survey techniques if the goal is to obtain extended
information. However this category is not necessarily the most expensive of all,