PhD ThesisTravel behaviour research aims to inform and provide evidence for sound transport
policy. Excess travel, where individuals demonstrate excessive use of for example time
or distance, challenges assumptions underpinning fundamental beliefs of travel
behaviour research where travel should be minimised in order to get to the destination.
This thesis explores the phenomenon of excess travel and the characteristics of people
exhibiting excess travel within a commuting context, using Tyne and Wear as a case
study. Building on existing definitions of excess commuting, which include time and
distance, this study gradually adds additional parameters of cost, effort, and many other
parameters (e.g. value of time, weights for walking and waiting) in the generalised cost
formula, and the final sample is analysed to identify similarities and differences
between excess commuters (EC) and not excess commuters (NEC). The methodology
uses a GIS technique for sampling and a questionnaire approach for data collection. The
final sample includes origin-based (home) commuters who completed a questionnaire
delivered to their home addresses, and destination-based (work) commuters who
completed an online version of the same questionnaire.
Analytical methods are used to identify EC and NEC based on self-reported (‘pure’)
values of the four key parameters of time, cost, distance and effort while commuting
and using a generalised cost approach. For the parameters of time and cost as well as for
the generalised cost results seven saving options are considered, where 5% savings is
the lowest option and 50% or more savings is the highest option. An analysis of various
attributes and their differences in medians together with a series of socio-economic
characteristics are used to distinguish between EC and NEC within the four groups in
total (time, cost, effort, generalised cost).
The results show that within the collected sample EC make up between 32% (in the cost
group) and 78% (in the effort group) of the total sample (depending on the
parameter/group considered), and that there are some statistically significant differences
at the 95% level between EC and NEC within the groups. The fact that the number of
EC varies between the groups is to be expected, as the literature review suggested that
taking different parameters into account produces different results. Generally, EC seem
to behave in a similar manner to the rest of the sample, in terms of most of the factors
tested, when making choices about commuting, but for example 41% of the respondents
ii
drive to work and within this driving group there are more EC than NEC (for example
44% of EC versus 37% of NEC within the time group or 52% of EC versus 36% of
NEC within the cost group). More importantly, the median values for the four key
parameters of travel to work (actual commute time, ideal one-way commute time,
commute cost, commute distance) are higher in majority of the cases for EC than for
NEC within the four groups. Attitudes and preferences also play a role, demonstrating
that the most frequent trip purpose, the commute, can provide some benefit to travellers.
The results also show that in terms of the activities such as listening to music/radio,
reading book/newspapers, exercising or concentrating on the road a majority of
statistically significant differences between EC and NEC occur within the cost and the
effort groups only. The demand for more direct routes and cheaper fares on public
transport is emphasised by the majority of the sample. The respondents tend to be well
informed about their travel to work alternative transport modes and different transport
planning tools available, and the Internet stands out as a primary source of information
employed by majority of both EC and NEC. In exploring the characteristics of EC and
NEC in more depth, recommendations are identified for public transport providers to
improve their services and encourage more commuters to transfer travel time into
activity time