Why Collecting Long and Short Distance Within National Travel Surveys?



Why Collecting Long and Short Distance Within National Travel Surveys?

Authors

J Armoogum, IFSTTAR

Description

The aim of this paper is two fold: first is to give some answer on how to
capture long distance mobility. Second is to describe the methodology we
developed to estimate the global individual annual mobility, according to
these data.

Abstract

Nationals travel surveys are generally design to give a picture of mobility at
the country level. It is the data source providing the most transverse and
consistent overview of mobility, whatever the modes and the transport
situations of people living in the country. For instance, the aim of the
French National Travel survey is the description of short and long distance
trips made by households living in France, as well as their access to (and use
of) public and private transport means. For achieving this goal, various data
collection methodologies have been proposed in recent decades in different
national contexts.

Generally, National travel surveys (NTS) combine different survey instruments
to measure different types of mobility. For daily mobility, a description of
the mobility done the day before the interview is asked. For long distance
journeys, the period under review is longer (it could from one month to three
months) to capture some journeys. One of the problem is that long distance
trip is very unevenly distributed in the population (e.g. 47% of individuals
made no trip over 100 km during at least 3 months before the interview,
according to the last National Travel Survey conducted in France).

It is of great interest to have the “real picture” of the mobility i.e. to
analyze short and long distance mobility together in a global treatment,
notably to elaborate exhaustive environmental assessments (CO2 and pollutant
emissions). For example in France, the mobility of a typical day (which is
considered as the “average” day) could be considered to be the local
mobility (trips described on one day only) measured on the day before. But, if
we consider the distance covered, the “real” local mobility represents
only 63% of the reality.

The aim of this paper is two folds, first is to give some answer on how to
capture long distance mobility with a discussion on sampling strategies,
Association for
European Transport ABSTRACT
Copyright, 2016. Association for European Transport. All rights reserved. Page 2
length of the periods under review and way to cope recall effect. Second is to
describe the methodology we developed to estimate the global individual annual
mobility, according to these data. This method depends on two different survey
instruments, where not the same days were described and where not the same
periods were covered. Therefore, we use a data fusion methodology to simulate
the overall mobility in France, balance which is essential to assess
exhaustive impacts in terms of energy consumption, pollutant emissions as well
as CO2 emissions.

Publisher

Association for European Transport