Filetype PDF | Posted on 16 Aug 2022 | 3 years ago
Authentication
digital resources
199x Filetype PDF File size 0.33 MB Source: projectwaalbrug.pbworks.com
Journal of Transport Geography 12 (2004) 127–140
www.elsevier.com/locate/jtrangeo
Accessibility evaluation of land-use and transport strategies:
review and research directions
Karst T. Geurs a,*, Bert van Wee b
a Netherlands Environmental Assessment Agency, National Institute for Public Health and the Environment, P.O. Box 1,
Bilthoven BA 3720, The Netherlands
b Delft University of Technology, Delft, The Netherlands
Abstract
A review of accessibility measures is presented for assessing the usability of these measures in evaluations of land-use and
transport strategies and developments. Accessibility measures are reviewed using a broad range of relevant criteria, including
theoretical basis, interpretability and communicability, and data requirements of the measures. Accessibility impacts of land-use and
transport strategies are often evaluated using accessibility measures, which researchers and policy makers can easily operationalise
and interpret, such as travelling speed, but which generally do not satisfy theoretical criteria. More complex and disaggregated
accessibility measures, however, increase complexity and the effort for calculations and the difficulty of interpretation. The current
practice can be much improved by operationalising more advanced location-based and utility-based accessibility measures that are
still relatively easy to interpret for researchers and policy makers, and can be computed with state-of-the-practice data and/or land-
use and transport models. Research directions towards theoretically more advanced accessibility measures point towards the
inclusion of individuals spatial–temporal constraints and feedback mechanisms between accessibility, land-use and travel behav-
iour. Furthermore, there is a need for theoretical and empirical research on relationships between accessibility, option values and
non-user benefits, and the measurement of different components of accessibility.
2003 Elsevier Ltd. All rights reserved.
Keywords: Accessibility; Land-use; Transport; Policy evaluation
1. Introduction Several authors have written review articles on accessi-
bility measures, often focusing on certain perspectives,
Accessibility, a concept used in a number of scientific such as location accessibility (e.g. Song, 1996; Handy
fields such as transport planning, urban planning and and Niemeier, 1997), individual accessibility (e.g. Pirie,
geography, plays an important role in policy making. 1979; Kwan, 1998) or economic benefits of accessibility
However, accessibility is often a misunderstood, poorly (e.g. Koenig, 1980; Niemeier, 1997). Our review differs
defined and poorly measured construct. Indeed, finding from existing review articles in the following ways.
an operational and theoretically sound concept of Firstly, accessibility measures are reviewed from differ-
accessibility is quite difficult and complex. As a result, ent perspectives, and we do not focus on one specific
land-use and infrastructure policy plans are often eval- perspective. The main purpose is to assess the usability
uated with accessibility measures which are easy to of accessibility measures in evaluations of both land-use
interpret for researchers and policy makers, such as and transport changes, and related social and economic
congestion levels or travel speed on the road network, impacts. Secondly, measures are reviewed according
but which have strong methodological disadvantages. to a broad range of relevant criteria, i.e. (a) theoretical
This paper presents a thorough review of accessibility basis, (b) interpretability and communicability, (c) data
studies and research directions to improve the current requirements and (d) usability in social and economic
practice of land-use and transport policy appraisal. evaluations. This review, based on an extensive litera-
ture study (Geurs and Ritsema van Eck, 2001), will
approach the different perspectives and components of
*Corresponding author. Tel.: +31-30-274-3918; fax: +31-30-274- accessibility in Section 2, the accessibility measures in
4417. Section 3 and explore the conclusions in Section 4. Fu-
E-mail address: karst.geurs@rivm.nl (K.T. Geurs). ture research paths will be outlined in Section 5.
0966-6923/$ - see front matter 2003 Elsevier Ltd. All rights reserved.
doi:10.1016/j.jtrangeo.2003.10.005
128 K.T. Geurs, B. van Wee / Journal of Transport Geography 12 (2004) 127–140
2. Accessibility measures: perspectives and components travel costs). The demand relates to both passenger
and freight travel.
Accessibility is defined and operationalised in several 3. The temporal component reflects the temporal con-
ways, and thus has taken on a variety of meanings. straints, i.e. the availability of opportunities at differ-
These include such well-known definitions as the po- ent times of the day, and the time available for
tential of opportunities for interaction (Hansen, 1959), individuals to participate in certain activities (e.g.
the ease with which any land-use activity can be reached work, recreation).
from a location using a particular transport system 4. Theindividualcomponentreflectstheneeds(depending
(Dalvi and Martin, 1976), the freedom of individuals to onage,income,educationallevel,householdsituation,
decide whether or not to participate in different activi- etc.), abilities (depending on peoples physical condi-
ties (Burns, 1979) and the benefits provided by a tion, availability of travel modes, etc.) and opportuni-
transportation/land-use system (Ben-Akiva and Ler- ties (depending on peoples income, travel budget,
man, 1979). In our study, accessibility measures are seen educationallevel,etc.)ofindividuals.Thesecharacter-
as indicators for the impact of land-use and transport istics influence a persons level of access to transport
developments and policy plans on the functioning of the modes (e.g. being able to drive and borrow/use a car)
society in general. This means that accessibility should and spatially distributed opportunities (e.g. have the
relate to the role of the land-use and transport systems skills or education to qualify for jobs near their resi-
in society, which, in our opinion, will give individuals or dential area), and may strongly influence the total
groups of individuals the opportunity to participate in aggregateaccessibility result. Several studies (e.g. Cer-
activities in different locations. Focusing on passenger vero et al., 1997; Shen, 1998; Geurs and Ritsema van
transport, we define accessibility as the extent to which Eck, 2003) have shown that in the case of job accessi-
land-use and transport systems enable (groups of) indi- bility, inclusion of occupational matching strongly af-
viduals to reach activities or destinations by means of a fects the resulting accessibility indicators.
(combination of) transport mode(s). Furthermore, the
terms access and accessibility in the literature are Fig. 1 shows the relationships between these compo-
often used indiscriminately. Here, access is used when nents and accessibility (as defined above), and relation-
talking about a persons perspective, accessibility when ships between the components themselves: here, the
using a locations perspective. land-use component (distribution of activities) is an
A number of components of accessibility can be important factor determining travel demand (transport
identified from the different definitions and practical component) and may also introduce time restrictions
measures of accessibility that are theoretically important (temporal component) and influence peoples opportu-
in measuring accessibility. Four types of components nities (individual component). The individual compo-
can be identified: land-use, transportation, temporal and nent interacts with all other components: a persons
individual. needs and abilities that influence the (valuation of) time,
cost and effort of movement, types of relevant activities
1. The land-use component reflects the land-use system, and the times in which one engages in specific activities.
consisting of (a) the amount, quality and spatial dis- Furthermore, accessibility may also influence the com-
tribution opportunities supplied at each destination ponents through feedback mechanisms: i.e. accessibility
(jobs, shops, health, social and recreational facilities, as a location factor for inhabitants and firms (relation-
etc.), and (b) the demand for these opportunities at ship with land-use component) influences travel demand
origin locations (e.g. where inhabitants live), (c) the (transport component), peoples economic and social
confrontation of supply of and demand for opportu- opportunities (individual component) and the time
nities, which may result in competition for activities needed to carry out activities (temporal component).
with restricted capacity such as job and school vacan- Following our definition of accessibility, an accessi-
cies and hospital beds. bility measure should ideally take all components and
2. The transportation component describes the transport elements within these components into account. In
system, expressed as the disutility for an individual to practice, applied accessibility measures focus on one or
cover the distance between an origin and a destina- more components of accessibility, depending on the
tion using a specific transport mode; included are perspective taken. Four basic perspectives on measuring
the amount of time (travel, waiting and parking), accessibility can be identified.
costs (fixed and variable) and effort (including reli-
ability, level of comfort, accident risk, etc.). This dis- 1. Infrastructure-based measures, analysing the (ob-
utility results from the confrontation between supply served or simulated) performance or service level of
anddemand.Thesupplyofinfrastructure includes its transport infrastructure, such as level of congestion
location and characteristics (e.g. maximum travel and average travel speed on the road network. This
speed, number of lanes, public transport timetables, measure type is typically used in transport planning.
K.T. Geurs, B. van Wee / Journal of Transport Geography 12 (2004) 127–140 129
Land-use component Transport component
locations and travel demand passenger and
characteristics freight travel
of demand
available travel time,
supply demand, opportunities costs, effort supply demand
competition
locations and location and
characteristics characteristics of
of opportunities infrastructure
Accessibility to
opportunities
Temporal component Individual component
• opening hours of shops time restrictions needs, abilities
and services opportunities • income, gender,
• available time for educational level
activities • vehicle ownership, etc.
available time
= direct relationship = indirect relationship = feedback loop
Fig. 1. Relationships between components of accessibility.
2. Location-based measures, analysing accessibility at of measure is founded in the space–time geography
locations, typically on a macro-level. The measures of Hagerstrand (1970) that measures limitations on
describe the level of accessibility to spatially distrib- an individuals freedom of action in the environment,
uted activities, such as the number of jobs within i.e. the location and duration of mandatory activities,
30 min travel time from origin locations. More com- the time budgets for flexible activities and travel
plex location-based measures explicitly incorporate speed allowed by the transport system.
capacity restrictions of supplied activity characteris- 4. Utility-based measures, analysing the (economic) ben-
tics to include competition effects. Location-based efits that people derive from access to the spatially
measures are typically used in urban planning and distributed activities. This type of measure has its
geographical studies. origin in economic studies.
3. Person-based measures, analysing accessibility at the
individual level, such as the activities in which an Table 1 presents a matrix of perspectives on accessi-
individual can participate at a given time. This type bility and components. The table shows each perspective
Table 1
Perspectives on accessibility and components
Measure Component
Transport component Land-use component Temporal component Individual component
Infrastructure-based Travelling speed; vehicle- Peak-hour period; 24-h Trip-based stratification, e.g.
measures hours lost in congestion period home-to-work, business
Location-based measures Travel time and or costs Amount and spatial Travel time and costs may Stratification of the
between locations of distribution of the demand differ, e.g. between hours population (e.g. by income,
activities for and/or supply of of the day, between days educational level)
opportunities of the week, or seasons
Person-based measures Travel time between Amount and spatial Temporal constraints for Accessibility is analysed at
locations of activities distribution of supplied activities and time avail- individual level
opportunities able for activities
Utility-based measures Travel costs between Amount and spatial Travel time and costs may Utility is derived at the
locations of activities distribution of supplied differ, e.g. between hours individual or homogeneous
opportunities of the day, between days population group level
of the week, or seasons
130 K.T. Geurs, B. van Wee / Journal of Transport Geography 12 (2004) 127–140
to focus on a certain component, ignoring other relevant only have a direct impact on accessibility but also an
elements of accessibility. Infrastructure-based measures indirect impact, via the transport system. E.g. more
do not include a land-use component; i.e. they are not urbanisation in a densely populated area might increase
sensitive to changes in the spatial distribution of activ- congestion levels, and so the disutility of travel. This
ities if service levels (e.g. travel speed, times or costs) impact is expressed via the transport component.
remain constant. The temporal component is explicitly Thirdly, a measure should be sensitive to temporal
treated in person-based measures and is generally not constraints of opportunities. Finally, a measure should
considered in the other perspectives, or treated only take individual needs, abilities and opportunities into
implicitly, for example by computing peak and off-peak account. In addition, from these general criteria the
hour accessibility levels. Person-based and utility-based following five criteria can be derived according to which
measures typically focus on the individual component, an accessibility measure should behave, keeping all
analysing accessibility on an individual level. Location- other conditions constant:
based measures typically analyse accessibility on a
macro-level, but focus more on incorporating spatial 1. If the service level (travel time, costs, effort) of any
constraints in the supply of opportunities, usually ex- transport mode in an area increases (decreases),
cluded in the other approaches. accessibility should increase (decrease) to any activity
in that area, or from any point within that area.
2. If the number of opportunities for an activity in-
3. Review of accessibility measures creases (decreases) anywhere, accessibility to that
activity should increase (decrease) from any place.
3.1. Criteria for accessibility measures 3. If the demand for opportunities for an activity with
certain capacity restrictions increases (decreases),
This section reviews the different types of accessibility accessibility to that activity should decrease (in-
measures according to relevant criteria. Although there crease).
is no best approach for accessibility because different 4. An increase of the number of opportunities for an
situations and purposes demand different approaches activity at any location should not alter the accessibil-
(Handy and Niemeier, 1997), several criteria can be ity to that activity for an individual (or groups of
derived to evaluate the usefulness and limitations of individuals) not able to participate in that activity
accessibility measures for different study purposes. Such given the time budget.
criteria can for example be found in Black and Conroy 5. Improvements in one transport mode or an increase
(1977), Jones (1981) and Handy and Niemeier (1997). of the number of opportunities for an activity should
Here, we use criteria from the perspective or our defi- not alter the accessibility to any individual (or groups
nition of accessibility and the usefulness of the concept of individuals) with insufficient abilities or capacities
of accessibility in evaluations of land-use and transport (e.g. drivers licence, education level) to use that mode
changes. Our criteria are: (1) theoretical basis, (2) op- or participate in that activity.
erationalisation, (3) interpretability and communicabil-
ity, and (4) usability in social and economic evaluations. These criteria should not be regarded as absolute but
The criteria are described in short below. more in the line of what accessibility studies should
strive for. Applying the full set of criteria would imply a
3.1.1. Theoretical basis level of complexity and detail that can probably never be
An accessibility measure should ideally take all achieved in practice. However, it is important that the
components and elements within these components into implications of violating one or more of theoretical
account (see Section 2). Thus, an accessibility measure criteria should be recognised and described.
should firstly be sensitive to changes in the transport
system, i.e. the ease or disutility for an individual to 3.1.2. Operationalisation
cover the distance between an origin and a destination This is the ease with which the measure can be used in
with a specific transport mode, including the amount of practice, for example, in ascertaining availability of
time, costs and effort. Secondly, an accessibility measure data, models and techniques, and time and budget. This
should be sensitive to changes in the land-use system, i.e. criterion will usually be in conflict with one or more of
the amount, quality and spatial distribution of supplied the theoretical criteria described above.
opportunities, and the spatial distribution of the de-
mand for those opportunities, and the confrontation 3.1.3. Interpretability and communicability
between demand and supply (competition effects). Researchers, planners and policy makers should be
Accessibility measures which do not account for com- able to understand and interpret the measure, otherwise
petition effects may lead to inaccurate or even mislead- it is not likely to be used in evaluation studies of land-
ing results (Shen, 1998). Note that land-use changes not use and/or transport developments or policies, and will
no reviews yet
Please Login to review.
