Socio-Economic Planning Sciences 35 (2001) 175188

Strategic analysis of public transport coverage

Alan T. Murray*
Department of Geography, The Ohio State University, 1036 Derby Hall, 154 North Oval Mall,
Columbus, OH 43210-1361, USA

Abstract

Public transport service provision is viewed as an important component of the overall transportation
planning and management process. Research examining public transportation performance and how it may
be enhanced is much needed. This paper addresses strategic aspects of service access. Public transport in
Brisbane, Australia is evaluated using a commercial geographical information system integrated with
various spatial analytical techniques including a location covering model. The developed strategic analysis
approach is eective for justifying local modications to the public transport system with respect to system
ineciencies and also allows this to be done with signicant user (or public) input. Such strategic
approaches are likely to result in higher regional utilization of public transportation. r 2001 Elsevier
Science Ltd. All rights reserved.

Keywords: Access; Location set covering; Service eciency

1. Introduction

Population growth exerts considerable pressure on infrastructure and natural resources in

urban regions. One of the most obvious in daily life is the transportation system, both in terms of
how it impacts the environment and the congestion typically experienced in most cities. How
additional transportation demand will be served in growing urban regions is considered to be an
important issue for achieving sustainability. Indeed, the relationship between the transportation
system, urban form, trip demand, and energy use is paramount in addressing the challenges
presented by urban growth. This may be attributed to the considerable economic ineciency and
environmental degradation associated with excessive private vehicle travel based on current
technology [1,2]. For these reasons, public transportation is recognized as a key component in the
management and planning of urban regions [3]. Public transport represents a means by which

*Corresponding author. Tel.: +1-614-688-5441; fax: +1-614-292-6213.

E-mail address: murray.308@osu.edu (A.T. Murray).

0038-0121/01/$ - see front matter r 2001 Elsevier Science Ltd. All rights reserved.
PII: S 0 0 3 8 - 0 1 2 1 ( 0 1 ) 0 0 0 0 4 - 0
176 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

people can eciently move throughout a region with the least amount of impact on the
environment. However, automobile travel oers individuals more freedom and exibility in
movement. Most urban regions in Australia and the United States, in particular, must contend
with inherent automobile dependence and a reluctance of individuals to make a switch to public
transportation.
The challenge for urban planners and decision makers is to identify eective strategies for
dealing with resistance to travel by public transport. One important factor is ensuring that the
regional public transport system is a viable travel alternative [4]. In particular, the system must get
people from where they are to where they need to go in a reasonable amount of time. Most urban
regions with existing public transportation typically do a relatively good job at ensuring that stops
and routes are established to sensibly serve origins and destinations. Those systems with low
utilization rates, however, tend to have more diculty competing with automobile travel times [2].
From the previous discussion, access provision and system eciency are both important
elements of public transport service. Thus, strategic modeling and analysis approaches are needed
for evaluating public transport access and eciency within the context of regional policies. This
will better facilitate debate and discussion regarding the eectiveness of current services as well as
establish a framework for developing system changes that ultimately provide better service.
In this paper, public transport access and eciency is examined in Brisbane, Australia, the
major urban center of the southeast Queensland region. Southeast Queensland is comprised of
Brisbane, the Sunshine Coast, and the Gold Coast and contains approximately 2.1 million people.
Population growth in the region from 1991 to 1996 was approximately 300,000 people, a
continuing trend over the past two decades. Brisbane has less than half of the regional population,
containing 806,292 people. Regional public transport policies and goals are well dened for
Brisbane in the Integrated Regional Transport Plan [3], so this makes the associated analysis
eort an essential component of the overall planning process. Public transport in the Brisbane
region consists of bus, rail and ferry services, with bus being the dominant mode.
This paper evaluates public transportation service in Brisbane using geographical information
systems (GIS) based spatial analysis techniques. The next section reviews relationships between
transportation and sustainability. Public transport access is then examined in Section 3. A spatial
model for identifying ineciencies in public transport access coverage is presented and applied in
Section 4. The implications of this analysis for public transportation in Brisbane are then
discussed. Finally, conclusions and future directions are provided.

2. Transportation and sustainability

Urban regions, whether changing or growing, or both, are increasingly aware of the need to
create better environmental, social and economic conditions over the short and long terms.
Addressing these conditions is the basis for moving cities and regions towards a more sustainable
existence. The relationship between transportation and sustainability is rather obvious and has
been explored by a number of researchers [1,5,2,6]. Per capita energy use has a major inuence on
sustainability. Comparative studies on energy use in urban centers [2] have found linkages
between population density and energy consumption. For example, low density cities found in
 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188 177

North America and Australia have been shown to be considerably less ecient than compact
European cities [2].
The implications for transportation are obvious given its use of, and reliance on, non-renewable
resources as well as the generation of negative externalities in the form of increased congestion
and air and noise pollution. In addition, transportation systems contribute to the social qualities
and attributes of a region. The ability to maintain ones network of family and friends is vital to
perceptions of quality of life since transportation provides the means for this interaction. The
economic prosperity of a region is tied directly to the transportation services provided, with one of
the primary activities being the distribution of goods and service. In all, there is an inter-
connectivity and dependency upon the various elements of sustainability and transportation.
In southeast Queensland, where population growth has been substantial, addressing issues of
sustainability has been recognized as being essential [7]. In fact, transportation, and public
transport in particular, receives considerable attention and is seen as a key element in addressing
sustainability concerns in the region [3]. A major priority is to increase public transport utilization
rates, which are currently less than 7% of total trips taken. It is recognized that major changes are
in order if public transport is to be a more eective travel mode option. However, little has been
done to evaluate policy goals and system performance, particularly, with respect to access and
eciency of the public transport services in Brisbane.
Since World War II, public transport systems of Western cities have been declining as access to
private vehicles has increased along with the development of highways and interstates [2]. During
this period, public transport systems have largely proven to be unprotable, resulting in reduced
service levels. Subsidies have traditionally been provided by government agencies in order to
ensure some level of mobility for the transport disadvantaged, such as the poor and elderly, as
well as provide a commuter alternative in more congested regions [8].
As in many cities, the Brisbane tram system was dismantled in the late 1960s and replaced with
a exible bus system. These decisions now appear to have been myopic as tram and light rail
services are being re-introduced throughout the world. With the benet of hindsight, maintaining
separate tram corridors could have been a good basis for strengthening public transport usage in
Brisbane, and in other regions. At the least, cost outlays that would now need to be absorbed
could have been avoided if this infrastructure still existed. However, the English experience has
found that despite increased innovation, fare reductions, and higher service levels brought about
by competition, few additional customers have been attracted to public transport [9]. Given that
the more recent major public transit projects in the United States, as an example, have not
necessarily altered travel behavior [1], strategies that require substantial investment could be quite
risky. Nevertheless, many successful public transport projects in recent times may be identied [2].
Increasing public transport utilization in Brisbane, however, is not a simple or straightforward
endeavor.
One method for addressing the substitutability of mode selection is to make the price of private
vehicle travel more expensive and thereby increase public transport use. Economists have long
stated that the way to reduce congestion is to charge motorists the marginal social cost of their
actions [10]. This would ensure that each motorist pay for the externalities caused by vehicle use at
particular times of the day, such as heavy congestion and pollution periods. Road user charges are
a reality in Singapore and electronic road pricing has been or is being tested in cities like Hong
Kong and Los Angeles [11]. The Bureau of Transport and Communications Economics has
178 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

examined road pricing in Australian capital cities and found that high costs for road use would in
fact reduce private vehicle dependence [12]. However, the political realities appear to be that road
pricing is too risky, regardless of its feasibility, as it is not being pursued. This leaves reductions in
private vehicle travel to measures such as car pooling, telecommuting, or the increased use of
public transport. Achievement through public transport services would require, at the least:

* more eective price structures;

* enhanced travel comfort;
* better suitability and convenience of serviceFquality;
* reductions in travel timeFeciency; and
* increased service access.

Each of these issues is important and worthy of further study. This paper will be limited to the
last two items through the examination of access and eciency issues related to public transport
service provision.

3. Access to public transportation

A critical factor in public transport use is the access time or distance that someone is forced to
overcome to get to a service stop. This is in contrast to the operation and connectivity of the
public transport system. There is origin- and destination based access. The former may be
considered the distance from ones residence to their nearest public transport service stop, whereas
the latter represents the distance from ones desired trip target to its nearest public transport
service stop. Access to public transport is an important service performance measure and is
expressly recognized in most regional transportation plans [4]. In fact, regional transport planning
guidelines for Brisbane specify an origin based access goal of 400 m to a public transport service
stop for 90% of the total population [3]. This strategic policy is directed at increasing public
transport utilization, so assessment of this performance measure is important for informing the
planning and management process. Approaches for evaluating public transport access are detailed
in Murray et al. [4].
The lowest spatial resolution of information associated with where people reside is the
collection district level of the Australian Bureau of Statistics census hierarchy.1 This divides
806,292 people of the Brisbane statistical sub-division into 1538 spatial areas. The most recent
population information for analysis is from the 1996 census. Spatial information in the form of
public transport stops and routes was provided by the Passenger Transport Division of
Queensland Transport for southeast Queensland. There are 10,909 public transport service stops
located throughout the region, the majority of which are bus stops (98%). Given this, the focus of
the analysis is limited to only bus service provision. The Brisbane sub-region contains roughly
7600 bus stops within its statistical sub-division boundary.
1
Although cadastral information exists at an even ner spatial resolution, cadastral information does not report
census oriented statistics like population or socio-economic characteristics. Given this, it is not suitable for the analysis
carried out in this research.
 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188 179

Fig. 1. Public transport access coverage in Brisbane.

Measuring regional access to public transport has been discussed in detail in Murray et al. [4]
and may be determined by evaluating the proximity of an area to its closest public transport stop
in relation to a distance or travel time standard. For Brisbane, the suitable access standard is
stipulated as 400 m from an area to a stop. Thus, we may compute the minimum distance from a
collection district to its nearest bus stop. If this distance is within the standard, then the area is
considered to have suitable access to public transportation. In the current analysis, we utilize the
collection district centroid as a representative location for an area and measure distance to
transport stops using the Euclidean metric.2 The evaluation of access coverage is structured in
ArcView version 3.2 [13] using Avenue scripts for real-time user interactive exploratory spatial
data analysis. The user is prompted to identify the spatial layer being covered (collection districts),
the attribute of interest (total population), the spatial layer providing coverage (bus stops), and an
access standard. Processing and display of results takes less than a minute on a Pentium III/600
personal computer for this region.
In Brisbane, 86% of the total population is provided suitable access to public transport using
the 400 m standard. The areas served within the 400 m standard are highlighted in Fig. 1. The city
center is well served by public transport, so Fig. 1 reects an outward access coverage pattern

2
It is worth noting that alternative approaches exist for evaluating access proximity (see [4]). The access results
presented for the region under study here are consistent with alternative techniques such as buering and areal
interpolation of layers.
180 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

Fig. 2. Access coverage tradeo curve.

from the city. An important consideration before interpreting these ndings is assessing the
sensitivity of total population covered in relation to the access standard utilized. Such an
evaluation may be done by varying the suitable access standard. This is summarized for Brisbane
in Fig. 2, which shows access standard distances plotted against total population covered. In the
gure, distance standards ranging from 200 to 600 m in 50 m increments are depicted. Total
population covered ranges from 53.04% for 200 m to 93.26% for 600 m.
Given that there are no major jumps in the percentage of total population covered around the
400 m standard, it may be concluded that there exists reasonable stability in access coverage.
Thus, some general conclusions may be drawn from the use of the 400 m standard. Brisbane
essentially achieves the policy goal of suitable access coverage being provided to 90% of the
regional population. Although this strategic planning goal is supposed to contribute to an
increased use of public transportation, the overall percentage of trips taken using public transport
has steadily decreased in the past decade. Obviously, increasing the use of public transport will
require more than addressing access issues in the planning and management of urban growth. In
fact, the eciency of public transport is recognized as essential in that it must be more competitive
with automobile travel times [2]. The important point here is that strategic regional planning tends
only to focus on public transport access, which is found to be relatively good in the Brisbane
region. However, the utilization of public transport is very low. Given this, it is important that
alternative strategic approaches be developed and utilized in the analysis of public transportation
service provision, if current trends of decreasing public transport utilization are to be altered.

4. Strategic analysis of stop placements

It is clear that access is only one element contributing to individuals electing to travel by public
transport. Another consideration is travel time competitiveness. For this reason, public transport
 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188 181

Fig. 3. Stop placement redundancy.

must strive to achieve origindestination travel times that are relatively competitive with
automobile travel. Bus-based transit systems must, therefore, be concerned with developing
appropriate routes that can be served eciently. Clearly, fewer stops along a particular route
increase the potential for bus travel speeds to be competitive with private vehicle speeds. However,
stop placement should not be reduced to the extent that it decreases access to public
transportation. In addition to stop minimization, public transport travel speeds may be further
enhanced through strategies such as dedicated transit lanes and integration with higher speed light
rail systems.
A critical issue, then, is what constitutes stop redundancy or ineciency. Given the use and
interpretation of the access standard, an approach for assessing system eciency would be
whether or not individual stops provide additional access coverage. As noted previously, the
access standard in Brisbane is 400 m, so if a stop fails to provide coverage that would not
otherwise exist, it is not enhancing regional access to public transport and its usefulness could be
questioned. For example, Fig. 3 shows three pairs of bus stops along a route in Paddington (a
suburb of Brisbane). On either side of the road (Given Terrace), the stops are within 150 m of each
other. In this case, the middle pair of stops is not providing access to public transport, with respect
to the 400 m access standard, that does not otherwise exist. That is, the outer stops essentially
cover the same area served by the middle pair of stops; these stops may thus be considered
redundant. This establishes a basis for identifying system ineciencies in regional public transport
service. The implication is that performance improvements are possible given that fewer stops
served by appropriately structured routes reduce/minimize travel times from origins to
destinations.
Murray et al. discussed the likely existence of redundancy in service access coverage in Brisbane
[4]. Such superuous stop placement may do little or nothing to increase access to public
transport. Moreover, it likely increases system workload as there are more stops that must be
included in routes. This, in turn, increases travel time and decreases service quality. Eliminating as
much redundant transport stop access coverage as possible requires no institutional investment
and theoretically has no associated costs. There are numerous levels for rationalizing how the
analysis of service coverage redundancy is important. Perhaps the most signicant is its use as a
182 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

strategic eciency measure, much like the use of regional access coverage. In more operational
terms, identifying access coverage ineciencies represents an approach for assessing the existing
conguration of public transport stops. Given that stop congurations typically evolve over time,
it is quite valuable to engage in a system-wide or route level evaluation of service provision. Since
bus services are characteristically exible, such evaluation practices are an implicit feature of bus
transit.
Altering public services is typically a politically delicate issue. This has certainly been an issue in
public transportation service provision in Brisbane. Thus, it is important that impartial and
defendable approaches be utilized when evaluating and modifying such services as it will be
necessary to justify any and all changes to service provision. A strategically oriented approach
addressing service coverage in terms of inecient placement of stops is thus at the heart of making
public transport a more competitive and appealing travel option.

4.1. Modeling approach

A strategic approach for measuring the degree of redundancy and ineciency associated with
the placement of public transport service stops may be structured using the location set covering
problem (LSCP) proposed in Toregas et al. [14]. The LSCP was originally utilized for locating a
minimum number of emergency service facilities [14] and has also been suggested for identifying a
minimum number of express bus stop locations [15]. The use of the LSCP for assessing
redundancy in service stop coverage for an existing public transportation system does not appear
to be a previous application area.
Formulation of the LSCP for measuring system ineciencies utilizes the following notation:
i=index of service areas (entire set I);
j=index of current transport stops (entire set J);
dij shortest distance or travel time between area i and stop j;
S=access distance or travel time standard;
Ni fjjdij pSg;
(
1; if transport stop j is to remain in the service system
xj
0 otherwise:
Location Set Covering Problem (LSCP)
X
Minimize Z xj : 1
j

Subject to
X
xj X1 8i; 2
jANi

xj 0; 1 8j: 3
The objective (1) of the LSCP is to minimize the number of transport stops needed to provide
complete access coverage to the service region. Constraint (2) species that each area is to be
served by at least one transport stop. This ensures that all areas currently provided suitable access
 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188 183

coverage by the existing conguration of stops continue to be suitably served by the reduced
number of stops. Constraint (3) imposes integer restrictions on the decision variables. The model
structures a decision making process to determine which stops, in the existing conguration of
stops, should be kept.
The LSCP is a spatial variant of the set covering (or minimum cover) problem dened in
Edmonds [16] and Roth [17]. The dierence between the two models, aside from the spatial
context and application, is in the form of the objective function. The set covering problem
includes a weighting on the decision variables in the objective function
X
aj xj ; 4
j

where aj is a non-negative integer. Thus, the weight for each site is equal to one in the LSCP. The
LSCP and its more generic set covering extension are generally dicult to solve optimally for
medium and large problem instances. Research associated with the development of exact and
heuristic solution techniques for solving these problems is quite active. Although many advances
have been achieved in terms of capabilities for solving set covering problems using commercial
optimization software, heuristics continue to be developed and applied [18,19]. Lagrangian
relaxation heuristics have proven to be eective for solving relatively large problem instances
[1820].
As noted earlier, the evaluation of stop placement eciency was structured in ArcView version
3.2 coupled with a Fortran DLL (dynamic linked library) for real time user interactive
exploratory spatial data analysis. Processing, solving and display of results generally took less
than 1 min for the regional analysis of Brisbane. Solutions for the LSCP were obtained in the
structured spatial analysis environment using a Fortran DLL written by the author, which solves
the LSCP using a Lagrangian relaxation heuristic following the basic approach of Haddadi [19].3

5. Coverage eciency of public transportation in Brisbane

As noted previously, approximately 86% of the 806,292 people in Brisbane currently have
suitable access to public transportation based upon the 400 m standard (S 400). The developed
exploratory spatial data analysis tool enables potential redundancy or ineciency in service stop
placement to be identied. The planning problem involves 1538 service areas (collection districts)
and 7589 bus stops. Using the ArcView analysis module integrating the LSCP, we found that only
588 bus stops are necessary for the continued provision of suitable access for 86% of the total
population.4 That is, all areas currently characterized as having suitable access to public transport
can actually be served by a substantially reduced number of the current stops. Given that there are
7589 stops in the Brisbane region, this represents a 92% reduction of existing stops. Thus, less
than 1 in 10 stops are actually required to provide the current level of public transport access in
3
A limit of 200 iterations was imposed in the Lagrangian heuristic given the large problem instances. Solution quality
ranged from 0.28% to 5.58% of optimality, which is quite acceptable in such an analysis.
4
This particular problem has 7589 columns (variables) and 1538 rows (constraints). An attempt to solve the problem
optimally using Cplex verson 6.53 [21] was unsuccessful after 17 h of computational eort (1.5 million iterations and
550,000 branches).
184 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

Fig. 4. Strategic public transport stop placement.

the region. Fig. 4 depicts an inner city area of Brisbane, the suburb of St. Lucia, to highlight stop
placement ineciency in the region. Fig. 4 thus illustrates that there may in fact be considerable
room for enhancing system performance if some stops are eliminated. Strategic questions may,
therefore, be raised regarding the appropriateness of the current conguration of public transport
stops throughout Brisbane.
Before going further, we shall interpret the above results in more detail in order to reect upon
their signicance. There are 7589 bus stops, typically representing stop pairs on either side of a
road. This situation is depicted in Figs. 3 and 4. Given this, we would essentially need to double
the minimum number of stops identied using the LSCP to account for pairing of bus stops
(which ensures service in opposite directions on a street segment). The strategic measure of
ineciency thus indicates that 1176 stops (doubling 588) would actually be the minimum number
of stops necessary for complete coverage of those areas currently suitably served due to
operational considerations. This still represents an ineciency measure in the current
conguration of stops of 84.5%. That is, at an operational level, only 1 in 5 stops are actually
necessary to maintain current access provision. The comparison presented in Fig. 4 suggests that
the signicant reduction in necessary stops is in fact a result of the inecient spatial distribution
of public transport stops throughout the Brisbane region at this time.
The relationship between the minimum number of stops identied and various access standards
may also be explored. This is similar to what was done for access coverage in Fig. 2. Thus, a range
of access standards may be evaluated. The result is a tradeo curve showing solutions in relation
 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188 185

Fig. 5. Minimum required stops per access standard.

to the access distance and the minimum number of stops needed. This has been done for Brisbane
in Fig. 5 for access distances ranging from 300 to 500 m in 50 m increments. For example, if a
suitable access distance is thought to be 500 m for this region, then only 469 stops would be
necessary, whereas a suitable access distance of 300 m would require 715 stops in order to
maintain current coverage. Although the Fig. 5 results are rather intuitive, they help to illustrate
the subtle implications of varying regional public transport access standards in terms of a strategic
perspective of stop placement ineciency.

6. Discussion

The evaluation of tradeos associated with access coverage and stop placement eciency can
provide insight to policy evaluation and monitoring. The tradeo of access coverage by distance
standard shown in Fig. 2 gives some evidence that current strategic planning focused only on the
provision of suitable access will do little, if anything, to increase utilization of public transport in
Brisbane. After all, less than 7% of all trips in the region are taken using public transportation
and this proportion is decreasing. There are signicant implications in the evaluation of access for
the current regional policy goals and standards established for Brisbane, since suitable access is
essentially provided to 90% of the regional population. Current access coverage suggests that
performance enhancements to the public transport system are necessary if utilization rates are to
increase. In strategic terms, the LSCP provides a measure of coverage redundancies that may be
directly interpreted as stop placement ineciency. Based upon the stipulated access standard of
400 m, it was found that 84.5% of the bus system is technically not providing unique access
coverage in the Brisbane region. This means that there is potential for increasing average bus
186 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

speeds (and decreasing origindestination travel times) in order to make public transport more
competitive with private vehicle travel.
Strategic techniques for assessing stop placement and access coverage tradeos are a starting
point for the analysis of a regional public transit system. The process must be able to
accommodate localized user interaction. Accounting for this in various ways would ensure the
usefulness of strategic modeling tools, which provide direction for regional improvements. A
number of extensions are worth mentioning. First, allowing for sub-regional or individual area
access standards could be warranted. As an example, in the Brisbane city center it might be
appropriate to consider a suitable access distance of 100 m, while suburbs on the periphery might
be set at 450 or 500 m.
Second, the ability to adjust or modify solutions identied using the LSCP is critical. For
example, due to terrain conditions, we may want to ensure that certain stops are included in an
operational plan. The same may be true for route transfer stops. Thus, we could utilize the LSCP
to ensure that these stops remain in the nal system conguration and minimize the remaining
stops needed to provide complete coverage. All this may be readily accomplished in the developed
application environment. Third, incorporating diering levels of importance between stops in the
objective function of the LSCP, as structured in Eq. (4), could be important. Stops serving as
transfer locations, as an example, could have lower aj values than other stops. Finally, the
developed approach using the LSCP could be utilized in a more restrictive way in order to focus
on individual routes, suburbs or transport corridors.
The design of a transit system is certainly more complex and complicated than what could be
structured in any optimization problem or analysis package. The developed strategic modeling
approach presented in this paper provides a process for identifying system ineciencies based
upon established access measures. This information may then be used as a basis for debate or to
justify changes to the current public transport system. In the course of such discussion, numerous
alternative plans may be generated and evaluated. The developed exploratory tool also allows
planners to demonstrate how local changes have regional benets as well as positive eects on
system performance. That is, fewer stops along a particular bus route, as an example, will
undoubtedly mean shorter travel time along that route (assuming that each stop must be visited).
These are in fact all too important issues considering the diculty typically experienced in
modifying the exible bus-based public transit system in Brisbane. Once a stop is established, it
is often extremely dicult to change or alter its location. Developing community support for
system changes is essential in public service provision as individuals and local areas are often
resistant to change or to a perceived loss of services.
An interesting implication of this research for bus services in Brisbane is that freeing up even
one bus through the removal of ineciencies could establish a basis for providing additional
services to areas that do not currently have adequate public transportation service. Fig. 1 shows
the areas without suitable coverage; some or all of these areas could thus potentially be served if
eciencies were to be achieved. Further, Murray and Davis [8] identied numerous areas in the
Brisbane region that may be characterized as transport disadvantaged, which means that they
need transportation services (given their relative socioeconomic makeup) but do not currently
have suitable access to public transport. Additional such services could be dedicated to serve these
high priority areas. An extension of the LSCP would conceivably be required to assist in this
process.
 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188 187

7. Conclusions

Urban growth and change present challenges for regional development, particularly with
respect to issues of sustainability. Public transportation will no doubt continue to play a major
role in serving urban regions. In order to increase public transport use, service access and system
eciency are critical. An analysis of Brisbane, Australia was presented and illustrated the
potential for improving public transport service eciency while maintaining current levels of
access coverage for the region.
The location set covering problem is an important strategic modeling approach for assessing
public transport system ineciencies. Integration with ArcView makes this an eective
exploratory spatial data analysis tool. The public transport system in Brisbane was shown to
have user access coverage that essentially meets regional policy goals; yet, utilization is
particularly low. This suggests that changes to its public transport must improve system
performance. Strategic assessment measures are needed for evaluating the extent to which current
services may be enhanced. Use of our approach demonstrated that substantial redundancies exist
in the current conguration of service stops. In fact, 84.5% of the bus stops in the region were
found to provide no additional access coverage using the 400 m distance standard. The likely
implication of this is that signicant improvements in system performance are possible if some
ineciencies and redundancies are eliminated along routes. If a strategic planning objective is to
reduce private vehicle dependence and increase the reliance on public transportation, then changes
and modications are imperative. The developed analysis measure is suggested to be an important
component of the overall evaluation and provision of public transportation services.

Acknowledgements

This research was supported by a grant from the Australian Research Council while the author
was a research fellow at the University of Queensland in the Australian Housing and Urban
Research Institute. Discussions with Rex Davis associated with this research were particularly
insightful and are gratefully acknowledged. The author would like to thank the Editor-in-Chief
and anonymous referees for their constructive and detailed comments.

References

[1] Anderson W, Kanaroglou P, Miller E. Urban form, energy and the environment: a review of the issues, evidence
and policy. Urban Studies 1996;33:735.
[2] Newman P, Kenworthy J. Sustainability and cities: overcoming automobile dependence. Washington D.C: Island
Press, 1999.
[3] Queensland Government. Integrated regional transport plan for southeast Queensland. Queensland Government,
Brisbane, 1997.
[4] Murray A, Davis R, Stimson R, Ferreira L. Public transport access. Transportation Research D 1998;3:31928.
[5] Banister D, Watson S, Wood C. Sustainable cities: transport, energy, and urban form. Environment and Planning
B 1997;24:12543.
[6] Nijkamp P, Baggen J, van der Knaap B. Spatial sustainability and the tyranny of transport: a causal path scenario
analysis. Papers in Regional Science 1996;75:50124.
188 A.T. Murray / Socio-Economic Planning Sciences 35 (2001) 175188

[7] Stimson R, Western J, Mullins P, Simpson R. Urban metabolism as a framework for investigating quality of life
and sustainable development in the Brisbane-southeast Queensland metro region. In: Yuan L, Yuen B, Low C,
editors. Urban quality of life. Singapore: National University of Singapore, 1999. p. 14368.
[8] Murray A, Davis R. Equity in regional service provision. Journal of Regional Science 2001, submitted for review.
[9] Evans A. Competition and the structure of local bus markets. Journal of Transport Economics and Policy
1990;24:25581.
[10] Button K. Transport economics. Aldershot, England: Edward Elgar, 1993.
[11] Seik F. An advanced demand management instrument in urban transportFelectronic road pricing in Singapore.
Cities 2000;17:3345.
[12] Bureau of Transport and Communications Economics. Trac congestion and road user charges in Australian
capital cities (Report 92). Canberra: Australian Government Printing Service, 1996.
[13] Environmental Systems Research Institute, Inc. ArcView GIS 3.2, 1999.
[14] Toregas C, Swain R, ReVelle C, Bergman L. The location of emergency service facilities. Operations Research
1971;19:136373.
[15] Gleason J. A set covering approach to bus stop location. Omega 1975;3:6058.
[16] Edmonds J. Covers and packings in a family of sets. Bulletin of the American Mathematical Society 1962;68:494
9.
[17] Roth R. Computer solutions to minimum-cover problems. Operations Research 1969;17:45565.
[18] Caprara A, Fischetti M, Toth P. A heuristic method for the set covering problem. Operations Research
1999;47:73043.
[19] Haddadi S. Simple Lagrangian heuristic for the set covering problem. European Journal of Operational Research
1997;97:2004.
[20] Beasley J. A Lagrangian heuristic for set-covering problems. Naval Research Logistics 1990;37:15164.
[21] ILOG Inc. ILOG CPLEX 6.5 users manual, 1999.