| What do we mean by policy instruments?
Policy instruments are the tools which can be used to overcome
problems and achieve objectives. They include conventional
transport methods such as new infrastructure, traffic management
and pricing policies, but increasingly they also involve attitudinal
changes and use of information technology. Equally importantly,
land use changes can contribute significantly to the reduction
of transport problems. Policy instruments can be implemented
throughout a city (for example a fares policy), or in a particular
area (e.g. a light rail line), or at a particular time of
day (e.g. a parking restriction). In many cases they can be
implemented at different levels of intensity (e.g. for fares
or for service levels). Rarely will any one policy instrument
on its own tackle all of a city’s problems, or meet
all of its objectives. It is important, therefore, to develop
strategies which involve a combination of policy instruments;
we look at this further in Section
11.
What is the range of policy instruments?
We have identified over 60 types of policy instrument. There
are several ways in which they can be categorised; we have
chosen to do so by type of intervention: land use measures;
infrastructure provision; management of the infrastructure;
information provision; attitudinal and behavioural measures;
and pricing. We have then, as appropriate, considered separately
those which influence car use; public transport use; walking
and cycling; and freight. Experience with each of these policy
instruments is described more fully in a project report and
many are already included in our interactive Policy
Guidebook. The full range of instruments is shown in the
list below:
Land use measures
Development
densities and mix
Encouraging
public transport use through land use planning
Development pattern
Parking
standards
Developer contributions to the financing of infrastructure
Value capture taxes
Attitudinal and behavioural measures
Individualised
Marketing to Reduce Car Use
Flexible
working hours
Car clubs
Telecommunications
Company
travel plans
Ride sharing
Infrastructure measure
New road construction
New off-street
parking
New and upgraded rail lines
New stations
New
rail services on existing lines
Light rail
systems
Guided
bus systems
Park and
ride
Terminals and interchanges.
Cycle routes
Pedestrian routes
Pedestrian areas
Lorry parks
Transhipment facilities
Management of the infrastructure
Road maintenance
Conventional traffic management
Urban traffic
control systems
Intelligent
transport systems
Accident
remedial measures
Traffic
calming measures
Physical
restrictions
Regulatory
restrictions
Parking
controls
Public
transport service levels
Bus priorities
Bus Fleet
Management Systems
High occupancy
vehicle lanes
Cycle lanes
and priorities
Cycle parking
provision
Pedestrian
crossing facilities
Lorry routes
and bans
Road freight
fleet management systems
Information provision
Conventional
direction signing
Variable
message signs
Real-time driver information systems and route guidance
Parking
guidance and information systems
Conventional timetable and other service information
Real time passenger information
Trip planning systems
Operation
information systems
Static direction signs
Tactile footways
Pricing
Private
parking charges
Road user
charging
Vehicle
ownership taxes
Parking
Charges
Fuel taxes
Fare levels
Fare structures
Concessionary
fares
How should cities choose policy instruments?
It is often very difficult to determine how a city has chosen
the policy instruments which it decides to use. Often, as
with road schemes, they are proposals with a long history,
which are reconsidered every time a new strategy is developed.
There are usually good reasons why they have never been implemented.
It is much harder, but much more valuable, to start with a
clean sheet, consider the full range of policy instruments,
and decide which are likely to contribute most. There are
two good reasons for this. Traditional solutions often have
weaknesses which can be overcome by combining them with other
instruments; this is a key principle of strategy formulation,
as outlined in Section 11.
Some of the newer policy instruments, like awareness campaigns
and real time information, may well offer a significant contribution.
For both these reasons, it is far better to start with the
question: “Which of this list of policy instruments
should I consider?” rather than simply: “How best
can I make use of earlier proposals?”
How can problem-oriented planning help?
The list of problems is the most useful starting point for
this, but context will also be important. We have designed
our Policy Guidebook, KonSULT, to enable users to seek a shortlist
of instruments which are likely to be of most interest in
their circumstances. We are also investigating new techniques
for option generation which will be added to KonSULT as they
become available. Experience in other successful cities is
also useful; our case studies in Section
16 help with this. This is also an area in which participation
can be valuable. Users, providers and other stakeholders may
well have ideas which would otherwise be overlooked. Once
a first set of possible instruments has been identified, they
can be tested using the approach described in Sections
12 and 13. Our optimisation
procedures, outlined in Section
14, offer a more rapid way of selecting the best combination
of policy instruments from a longer initial list.
Why is it difficult to assess which policy instruments
will be best?
Unfortunately the evidence which is available on the performance
of many of these policy instruments is very incomplete. In
some cases this is because the policy instruments are novel,
and experience is still limited; this is true, for example,
for car clubs. In others we have simply failed to collect
the evidence on what impact key policy instruments have had.
This is particularly true of road building; the realisation,
too late, that new roads could generate new traffic is one
reason for policy on road building in some countries changing
so abruptly. It is important, therefore, that all of us take
the opportunity, when we implement significant changes, to
measure and evaluate their impacts, and make that information
available to others. This is particularly true of policies
which have been less successful than planned; even though
we may want to keep such experiences to ourselves, we can
help others avoid making the same mistakes. We consider this
further in Section 15.
Even where experience is available it may not be directly
relevant in another context. Light rail will work better in
larger cities than in smaller ones. Walking and cycling provision
are more important in high density areas than in lower density
ones. Parking controls are likely to be more effective in
city centres than elsewhere. Regulatory controls will be more
acceptable in some cultures than in others. For all of these
reasons it can be difficult to judge how transferable experience
with successful policy instruments will be. This is a further
reason for encouraging as much experience as possible to be
recorded.
What information is available?
Some projects have provided valuable information on certain
types of policy instrument. VeloInfo provides a website on
ways of selecting measures to support cycling; ARTISTS provides
guidance on the redesign of street space; City Freight offers
advice on the selection of measures to support, and control,
the movement of freight. However, these sources are not comprehensive,
and there is still limited guidance on many types of policy
intervention.
We have attempted to overcome these limitations on information
on policy instruments by producing a report which summarises
the literature and by developing our web-based Policy Guidebook,
KonSULT. The report, which was published in 2001, reviews
the literature on all 60 policy instruments. KonSULT, which
is designed to be more readily kept up to date, currently
includes fuller information on 40 of them, and is being expanded
to provide full coverage. For each policy instrument, it defines
the instrument and describes briefly how it works. It then
provides an assessment from first principles of its likely
impact on each of the policy objectives and problems highlighted
in Sections 7 and 8.
This is followed by a series of case studies and a summary
of the contexts in which the instrument is likely to be most
effective.
The user is able to select possible policy instruments for
further consideration from a list based on the categories
identified earlier in this section; by a keyword search; or
using a novel filter mechanism which allows the user to specify
the type of organisation they represent, the type of urban
area they are interested in, their principal objectives, the
main problems which they face, and the types of strategy which
they are pursuing. The last of these is based on the key strategy
elements highlighted in Section
11. The final element in the coverage of each instrument
is an assessment of the types of policy instrument which could
complement it, either in reinforcing its impact or in overcoming
barriers to its implementation. The treatment of barriers
follows that outlined in Section
10. A further development will provide fuller guidance
on the design of integrated strategies, and the potential
for synergy between policy instruments.
How can performance be assessed?
All of these policy instruments will affect the performance
of the transport system in one or more of three ways:
• By changing the demand for travel
• By changing the supply of transport facilities
• By changing the cost of provision and operation of
the transport system.
Initial responses (e.g. changes in mode) may lead to secondary
ones (e.g. increases in overcrowding). Each of these types
of change will in turn affect performance against the objectives
in Section 7. It is this
first principles assessment of the likely impact of a policy
instrument which helps to assess its potential contribution,
and KonSULT is structured on this basis.
Changes in demand
When faced with a new policy instrument, or with a change
in an existing one, such as a fare increase, the individual
traveller has a number of options as shown in the box.
The scale of response will depend on the circumstances. Those
who are directly exposed to a change will respond more strongly
than those for whom the impact is indirect. Those who have
fewer alternatives will be more reluctant to change. Longer
term responses may well be stronger, as people have more time
to respond, but the more dramatic responses such as changing
work or home will depend on how permanent the change in policy
appears to be. There is a substantial literature on such responses,
typically measured by elasticities of demand.
The level of change in demand can be determined by knowledge
of the change in the policy instrument in question and of
the relevant elasticity of demand. Demand elasticities are
generally calculated by estimating the proportionate change
in demand for a good or service resulting from a one percent
change in a measure of the supply of that good or service.
Demand can be measured in trips or in trip-km for a given
mode in a given circumstance. Supply can be defined in a number
of different ways, including price, travel time, frequency
or overall (“generalised”) travel cost and it
is important, in interpreting elasticities, to know which
definition is being used. In particular, price might relate
to “generalised cost”, whereby all monetary and
time-related costs to the user are bundled together, assigning
a value to the time elements, or it might be defined in relation
to one particular component of cost, e.g. fuel price or parking
cost. Elasticities can also be measured for demand for the
mode being affected (for example bus trips in response to
changes in bus fares) or for demand for a competing mode (for
example car trips in response to bus fares). The latter is
referred to as a cross-elasticity.
Changes in supply
Changes in the supply of transport can take a number of forms
as shown in the box, some of which will have a direct influence
on travellers, while others will only affect them if they
are perceived.
For most policy instruments, it will be clear how they affect
supply, but the scale of their impact may be difficult to
assess.
Interaction of demand and supply
The effects of demand and supply changes can best be interpreted
by an understanding of the shape of demand and supply curves.
A demand curve (see below) represents the way in which demand
(in say trips) on the x-axis changes as costs (on the y-axis)
rise or fall. A supply curve shows how costs of use, on the
y-axis, rise as the level of use, on the x-axis, rises. That
shown is a typical supply curve in a road network, in which
average costs rise slowly at first, as increased traffic results
in reductions in speed, and then rise much more rapidly as
capacity is reached and delays occur. A public transport supply
curve would reflect, instead, the extra costs of having to
wait for the next bus as bus capacity is reached. The intersection
of the demand and supply curve determines both the number
of users (X in the figure below) and the cost per user (Y
in the figure below). These in turn can be used to determine
the impact on both policy objectives and problems.
The way in which a policy instrument affects demand and supply
curves will vary, as illustrated in the figures below, which
represent five different types of change in the demand and
supply for car use. In the first figure, the capacity of the
road system has been increased, for example through traffic
management; the supply curve has changed, but the demand curve,
at least in the short term, has not, since the same number
of users would wish to travel at a given cost. As a result,
the number of users has increased, and the average cost of
use has fallen. In the second figure, the capacity has been
reduced, perhaps through a road closure; again the supply
curve has changed, but the demand curve has not; the number
of users has fallen, and the average cost increased. In the
third figure, the demand for car use has fallen, perhaps through
a reduction in public transport fares or a successful awareness
campaign; the demand curve has changed, but the supply curve
has not, since the costs of use at a given flow remain the
same. As a result, the number travelling has fallen, as has
the average cost of travel. In the fourth figure, the demand
for car use has risen, perhaps through a deterioration in
public transport services or an improvement in driver information.
Again, the demand curve has changed but the supply curve has
not; the number of car users has increased, as has the average
cost of travel (though in this case, improved information
may have reduced the perceived cost of use). In the fifth
figure one of the many possible combinations of the above
effects is shown. In this case, demand for car use has fallen,
as has the capacity for car use. This could result, for example,
from reallocation of road space to light rail. As a result
both the demand and supply curves have changed. The number
of car users has fallen, but the effect on average cost will
depend on the relative changes in the demand and supply curves.
Changes in costs
The principal types of costs are capital costs of new infrastructure,
operating and administration costs, and costs of maintenance
and replacement. These will be offset for some instruments
by income from users and from taxes. Changes in these costs
and revenues are crucial in determining whether an individual
policy instrument, or the overall strategy, is affordable.
It is often the case that low cost instruments will offer
greater value for money than major infrastructure projects.
The main types of change in cost are shown in the box.
Causal chain diagrams are particularly helpful in understanding
the interaction of these processes.
How does the Policy Guidebook work?
The coverage of each policy instrument in the Policy Instruments
Guidebook is structured into five sections:
1. A description of the policy instrument and the way in
which it operates, with more detail provided for those which
are less well known or more complex
2. A first principles assessment, which assesses in turn
the expected impacts on demand, supply and costs; considers
the resulting implications for objectives
and problems
and indicators,
both assessed on a -5 to +5 scale, with brief explanatory
text; identifies the main winners and losers, again assessed
on a -5 to +5 scale; and finally considers the severity
of the main barriers to implementation, on a 0-5 scale,
drawing on the general consideration of barriers in Section
6 below
3. Presentation of the evidence from both case studies and
desk studies, following a similar structure to that of the
first principles assessment
4. A summary assessment, which considers again the performance
against objectives and problems, based on the evidence available
(again on a -5 to +5 scale); assesses the likely contribution
of the instrument in a number of contexts ranging from city
centres, to higher and lower density suburbs, to smaller
towns, again on a 0-5 scale; and briefly discusses potential
side effects; and
5. identification of the complementary measures which are
most capable of overcoming adverse side effects and reinforcing
the performance of the instrument, as a link both to the
coverage of these complementary instruments.
Which policy instruments are likely to contribute
most to particular objectives?
Given the comments above, it is impossible to suggest a set
of policy instruments which will meet the needs of all cities.
So much depends on each city’s priority objectives,
the scale of the problems to be overcome, the policy instruments
which are already in place, the combination of new policy
instruments, the context within which they might be implemented,
and the barriers to be overcome in doing so. However, it is
possible to give general guidance on the types of policy instrument
which are likely to have the greatest impact on specific policy
objectives in four different types of area: city centres;
inner suburbs; outer areas; and smaller urban areas. The tables
show the extent to which each of the six types of policy instrument
is likely to contribute to each of the eight objectives listed
in Section 7. |
