VALUING URBAN REALM – BUSINESS CASES IN PUBLIC SPACES
Rob Sheldon and Chris Heywood
Accent
Paul Buchanan
Colin Buchanan
David Ubaka and Chris Horrell
Transport for London
1.
INTRODUCTION
1.1.
Background
To obtain funding for improvements, urban realm schemes require robust
business cases that demonstrate the benefits of investment outweighing the
costs. In order to make the case for improvements benefits can now be
assessed both qualitatively and quantitatively.
There is a strong qualitative case for investment in urban realm
improvements. As part of a mix of policies, urban improvements can
encourage walking, improve health outcomes, benefit the environment,
reduce congestion, enhance social cohesion and assist local economies.
However, in order to best demonstrate the case for funding, it is important that
benefits are also assessed quantitatively.
Traditionally, the benefits assessed for urban realm business cases are time
savings and safety benefits. Time savings are particularly important for
schemes that relieve crowding or re-phase pedestrianisation and partpedestrianisation schemes. However, many schemes have impacts that are
not covered by quantitative measurement of time savings and safety benefits.
In particular, this approach underestimates the benefits of schemes that
improve ambience.
More recently, ambience is being assessed quantitatively in Transport for
London (TfL) business cases. It is a measure of the improvement to the
quality of environment that users experience. However, in the past, few urban
realm schemes included valuation of ambience benefits in their business
case. Despite the fact that a variety of urban realm schemes focus on
improving the experience of users, benefits were not included. This put the
schemes at a disadvantage because:
•
It is difficult to prioritise between urban realm schemes. As a result,
obtaining funding can be more difficult as there is a lack of quantitative
evidence to suggest the scheme is the best option among alternatives
•
Other modes have a wider set of benefits included in evaluations. Since
other modes demonstrate ambience improvements, they may be better
placed to receive funding.
© Association for European Transport and contributors 2007
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The reason why ambience benefits have were not included in business cases
for urban realm improvements is that neither the methodology nor the data
was available.
This paper describes a study commissioned by TfL that was designed to
provide a methodology and the data required to allow ambience benefits to be
included in business cases for urban realm improvements.
1.2.
Objectives
Transport for London (TfL) commissioned Accent and Colin Buchanan to
conduct research into how users value improvements to the public realm. The
study built on work originally undertaken by Colin Buchanan in producing an
approach to valuing benefits for the Strategic Walks in London, and
subsequently extended by Accent with Colin Buchanan in preparing
innovative statement preference research. The design of the study formed a
pilot for the methodology as a way of exploring walking/urban design issues.
The output provided the data and methodology needed to include ambience
benefits in business cases for a wide variety of schemes.
The challenge of the project was to provide valuations to user benefits for
quality improvements to the pedestrian environment. In terms of a designing a
research methodology there were particular challenges in how complex
payment mechanisms and improvements could best be described to
respondents in relevant and easily understood way.
The study included four integrated phases:
•
Scoping study – in which Accent/Colin Buchanan worked with TfL
representatives to establish the parameters to be included in the
research. This included which potential improvements should be put to
respondents as well as which payment mechanisms should be tested
•
Qualitative research – focus groups were used to test the visuals and
descriptions to be used in the stated preference work. This was a key
phase that ensured the most appropriate language and stimulus was put
to respondents whilst testing the levels for each attribute.
•
Pilot of the stated preference approach
•
Quantitative stated preference study – quantitative hall tests were used
to provide data to deliver:
−
relative priorities for improvements to the urban realm for users of
specific parts of the Edgware Road and Holloway Road
−
willingness to pay for those improvements using three payment
mechanisms:
Council Tax
Public transport fares/joining cost
© Association for European Transport and contributors 2007
2
Rent
−
An evaluation system for public realm improvements that was to be
included in TfL business cases.
2.
QUALITATIVE WORK
2.1.
Methodology
A programme of six focus groups was held among pedestrian users of the
Edgware Road to help determine the most appropriate terminology and show
material to use in the state preference study.
2.2.
Crossing the Edgware Road
Crossing wait time was explored with the aim of using this as a potential value
of time measure.
Some respondents, particularly older respondents and those with children,
crossed the road at designated crossings and “wait for the green man”.
Younger respondents were more opportunistic and crossed where and when
they could. For the younger males, this would involve vaulting over the
barriers. The younger female respondents admitted to crossing first into the
middle of the lane, waiting in the middle and then going on to the middle of the
second lane before reaching the opposite pavement.
Where they did wait to cross the road, respondents talked of waiting “minutes”
before getting the green man.
This made it difficult to establish an acceptable crossing wait time.
2.3.
Texts and Pictures
Eighteen aspects of the walking environment were included in the qualitative
element of the research, chosen as proxies for parameters measured in the
Pedestrian Environment Review System 2.0 (PERS). Respondents were
given pictures representing these aspects and separate word cards. They
were asked to match them to explore the understanding of both the visual
images and the descriptive words used.
2.4.
Ratings and Descriptions
Respondents were then shown pictures representing different levels of each
aspect to explore which they thought were the best and worst and whether the
pictures successfully conveyed those levels.
© Association for European Transport and contributors 2007
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Those that worked best were where the same scene was used for each level
but amended using PhotoShop to provide the different levels. This ensured
that a direct comparison was being made between levels without any other
differences being taken, incorrectly, into consideration. An example is given
below, for Graffiti and Flyposting.
2.5.
Willingness to Pay for Improvements
A range of approaches were tested to see which was likely to be the most
successful in getting respondents to indicate any level, however small, of a
willingness to pay for improvements to the pedestrian environment along the
Edgware Road.
The payment vehicles used were Council Tax, public transport fares/journey
cost, rent, single donation and subscription.
Council Tax
Respondents were given two scenarios using Council Tax to explore
willingness to pay for improvements to the Edgware Road. One involved an
increase and the other a rebate.
Unsurprisingly, the mention of Council Tax provoked emotional responses
with respondents’ initial reactions being that they should not be expected to
pay any more than they do already to fund any improvements. However,
neither did they want the Edgware Road to become worse than it is now, and
generally understood the contradiction.
It was important to emphasise that the focus was solely on the part of the
Council Tax that pays for street maintenance, so that respondents had a
reference point (we suggested £75) against which to pitch their suggested
payments. Amounts in the region of £5 and £10 were suggested.
Another key issue was that respondents needed reassurance that the money
would definitely go towards the Edgware Road. With that reassurance, they
© Association for European Transport and contributors 2007
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were willing to accept the Council Tax as a means of paying for improvements
to the Edgware Road.
Journey Cost
Regardless of whether or not they use public transport, respondents were
asked to imagine that they were regular public transport users.
Older respondents, who do not pay bus fares, dismissed the idea of paying
anything at all. Other respondents felt that they would want any improvements
funded by fares to be made to public transport, not to the pedestrian
environment.
Donation/Subscription
Initially, if respondents showed no willingness to pay using the Council Tax or
journey fare scenarios, they were asked to say how much they would give as
a single, one-off donation that would they could be certain would go towards
improving the environment for pedestrians on the Edgware Road.
Respondents were more willing initially to make a payment under this
scenario. It avoided any negative associations they may have with Council
Tax and they assumed immediately that the money would be spent solely on
the Edgware Road.
Respondents offered £10 a year.
For the last group, this approach was revised slightly to become a
subscription scheme, whereby respondents were asked how much they would
pay, annually, as a subscription to the Edgware Road improvement scheme.
As with the donation approach, respondents were willing to pay through a
subscription. However, the range of money offered at this stage was varied
and seemingly unrealistic. This variation highlighted the weakness in the
subscription approach and raised some concerns at the willingness of
respondents to pay much larger sums of money to a subscription scheme
than they were through any other mechanism. Perhaps because they
considered a subscription scheme to be a very unlikely scenario, respondents
offered similarly unrealistic amounts. In contrast to the Council Tax approach,
they had no reference point against which to measure the amount they are
willing to pay.
Willingness to pay more on account of having “more disposable income” also
raised concerns. This response seemed much more in line with giving to a
charitable cause than with a genuine assessment of willingness to pay.
© Association for European Transport and contributors 2007
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3.
STATED PREFERENCE FIELDWORK
3.1.
Methodology
The method for the stated preference research was CAPI hall tests which
were held in two locations: Edgware Road and Holloway Road.
All respondents were recruited on street to quota. Respondents had to be
walking on the part of the road defined by a map of the area. The map also
indicated the area in which those termed “residents” lived.
The sample comprised residents and non-residents and two trip purposes:
leisure/shopping (where it is assumed that the trip is less time constrained)
and commuting.
The sample size of 600 was based on eight cells of 75 interviews each (a
recommended minimum cell size for stated preference).
3.2.
Attributes
There were fifteen attributes included in the research. Examples of some the
attribute levels and the photos (at the size they were shown to respondents)
that accompanied them are shown below.
View of the street
Blocked view of street
Mainly clear view of street
© Association for European Transport and contributors 2007
Clear view of street
6
Cycles on the pavement
Cyclists ride on pavement
3.3.
Cyclists allocated lane / own
space for riding on pavement
No cyclists on pavement
Stated Preference Exercises
There were four stated preference exercises. The first three traded the fifteen
variables.
An example layout for the first stated preference exercise is shown below.
The final exercise traded off the top and bottom levels of the preceding three
exercises. These were colour coded with blue as the “bottom” level and green
as the “top” level. An example of the screen layout for the fourth stated
preference exercise is shown below.
© Association for European Transport and contributors 2007
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3.4.
Results
Stated Preference 1
All levels for both samples were significant and had the correct sign. The most
important attribute in the first exercise for both samples was ‘good, bright,
even lighting after dark’ with ‘vehicles do not park on pavement’ the second
most important attribute.
Table 1: Output from Stated Preference Exercise 1
Holloway Road
Edgware Road
View of the street
coefficient
t-stat
coefficient
t-stat
Mainly clear view of street1
0.8482
7.9
0.7772
7.2
Clear view of street1
0.6158
4.9
0.5438
4.3
Kerbs
Sloped kerb2
0.605
5.2
0.9317
8
Completely flat crossing2
0.7759
6.5
0.9998
8.2
Street lighting
Reasonably bright, patchy lighting after dark3
0.7575
6.4
1.151
9.4
3
Good, bright, even lighting after dark
1.358
10.3
1.765
12.7
Vehicles on the pavement
Vehicles do not park on pavement4
1.255
14.8
1.611
18
Cycles on the pavement
Cyclists allocated lane / own space for riding
0.6816
5.4
1.129
8.7
on pavement5
5
No cyclists on pavement
0.5011
4.2
0.8774
7.3
1. compared to Blocked view of street
2. compared to Step at kerb
3. compared to Very poor lighting after dark
© Association for European Transport and contributors 2007
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4. compared to Vehicles park on pavement
5. compared to Cyclists ride on pavement
Stated Preference 2
For the Edgware Road sample all levels were significant but both the levels of
the number of people in daylight were negative: ‘busy but not crowded.’ and
‘very crowded so that walking pace is badly affected’. In other words both of
these were seen as worse than the base level: ‘street (nearly) deserted.’
For the Holloway Road sample one level was insignificant: ‘busy but not
crowded.’ As for the Edgware Road sample both the levels of the number of
people in daylight were negative.
Table 2: Output from Stated Preference Exercise 2
Number of people in daylight
Very crowded so that walking pace is
badly affected1
Busy but not crowded1
Number of people after dark
A few people around after dark2
2
A lot of people around after dark
Pavement condition
Pavement cracked but even3
Pavement has no cracks and is even3
Graffiti and fly-posting
Generally free from graffiti / flyposting4
4
No graffiti / flyposting
Litter
Generally free from litter and chewing
5
gum
Generally free from litter and no chewing
gum5
Holloway Road
coefficient
t-stat
Edgware Road
coefficient
t-stat
-0.4105
-4.4
-0.5527
-5.5
-0.0908
-0.8
-0.3562
-2.8
0.3507
0.5622
3.6
5.1
0.3241
0.4379
3.1
3.8
1.141
1.288
11.4
10.8
1.354
1.744
12.7
13.3
0.644
0.8946
5.4
7.2
0.7991
1.226
6.3
9.3
0.7705
6.8
0.9338
7.9
1.371
11.3
1.507
11.8
1. compared to Street (nearly) deserted
2. compared to Street (nearly) deserted after dark
3. compared to Pavement cracked and uneven
4. compared to Significant graffiti / flyposting
5. compared to Significant litter and chewing gum
Stated Preference 3
All levels for both samples were significant and had the correct sign.
The most important attributes for both samples were in the crossing the street
variable: ‘direct green man crossing’ followed by ‘green man crossing in
stages’.
Table 3: Output from Stated Preference Exercise 3
Signs to public transport and attractions
Signs to public transport1
Local area maps, information boards and
signed routes1
Plants and public art
Holloway Road
coefficient
t-stat
Edgware Road
coefficient
t-stat
0.4102
3.9
0.5616
5.4
0.7962
7.5
0.9336
8.8
© Association for European Transport and contributors 2007
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Plants alongside street2
Plants alongside street and public art in
well chosen locations2
Seating
Seating areas at well chosen locations3
Crossing the road
Green man crossing in stages4
Direct green man crossing4
Physical intrusion of traffic
Traffic flow is safe to cross and there is
little or no noise5
0.4694
4.9
0.432
4.6
0.6173
7
0.6063
6.9
0.7851
11.1
0.9207
12.4
0.8226
0.9752
9
8.9
1.078
1.461
11.3
12.6
0.5965
7.6
0.5965
7.6
1. compared to No signage
2 compared to No plants or public art
3 compared to No seating areas
4 compared to No green man crossing
5 compared to Traffic flow prevents crossing and there are high levels of noise
Stated Preference 4
The fourth stated preference exercise showed the attributes from first three
exercises each at two levels, the base level and the ‘top’ level.
For both samples all levels were significant and had the correct sign. Package
1 was the most important attribute and Package 3 was the second most
important for both samples.
Table 4: Output from Stated Preference Exercise 4
Package 1
Package 2
Package 3
Holloway Road
coefficient
t-stat
1.077
12
0.7435
9
0.9334
10.4
Edgware Road
coefficient
t-stat
1.184
13.1
0.9197
11
1.143
12.5
The coefficients for the first three exercises can be ranked in order of the size
of their coefficients – the larger the coefficient the more important it is.
However, the coefficients from the three exercises needed to be linked. To do
this the values of the fourth stated preference exercise were used as follows.
To scale the coefficients for the three ‘lower’ level exercises to the final
exercise, first of all the coefficients for the top levels for each exercise were
summed.
So, for example, for Stated Preference exercise 3, the sum of the top level
coefficients for the Holloway Road sample was 3.7703 when compared with
the lowest levels:
•
•
•
•
•
•
Local area maps, information boards and signed routes
Plants alongside street and public art in well chosen locations
Seating areas at well chosen locations
Direct green man crossing
Traffic flow is safe to cross and there is little or no noise
Total
© Association for European Transport and contributors 2007
0.7962
0.6173
0.7851
0.9752
0.5965
3.7703
10
Then each coefficient was multiplied by the coefficient for the Exercise 3 top
level (0.9334) divided by the sum of the top level coefficients. For example,
the value for ‘direct green man crossing’ is:
•
Direct green man crossing: 0.9752 * (0.9334/3.7703) = 0.241426857
Finally, all the values were scaled to 100. Figure 1 shows the scaled values
for the whole sample. The attributes are ordered by the ‘top’ level attribute. If
there were values for two attributes within a topic, for example ‘direct green
man crossing’ and ‘green man crossing in stages’ within ‘crossing the road’,
then the ‘lower’ level is shaded light green in the chart.
Figure 1: Ranked attributes
Good, bright, even lighting after dark
7.21
4.40
Reasonably bright, patchy lighting after dark
6.62
Vehicles do not park on pavement
6.42
Direct green man crossing
Green man crossing in stages
5.01
6.17
Pavement has no cracks and is even
5.10
Pavement cracked but even
Generally free from litter and no chew ing gum
5.90
3.48
Generally free from litter and chew ing gum
4.57
Local area maps, information boards and signed routes
2.57
Signs to public transport
Seating areas at w ell chosen locations
4.49
4.31
No graffiti / flyposting
2.94
Generally free from graffiti / flyposting
No cyclists on pavement
3.18
Cyclists allocated lane / ow n space for riding on pavement
4.17
Completely flat crossing
4.11
3.56
Sloped kerb
Clear view of street
2.68
3.76
Mainly clear view of street
3.23
Plants alongside street and public art in w ell chosen locations
Plants alongside street
2.38
Traffic flow is safe to cross and there is little or no noise
3.15
A lot of people around after dark
*
-1.94
A few people around after dark
-2
-1
0
1
2
3
4
5
6
7
8
9
10
Base: 600
© Association for European Transport and contributors 2007
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Payment mechanisms
Three payment mechanisms were tested:
•
•
•
Council Tax
Rent
Public transport fares
For each a transfer pricing approach was used. This asks respondents
whether they would pay a set amount. If they say no, the amount is reduced. If
they say yes the amount is increased. If they say yes again they are asked
what is the maximum they would pay.
Council Tax
The Council Tax payers were asked questions about their willingness to pay
more Council Tax for the improvements they has just seen in the stated
preference.
There were three price points: £5, £2 and £10 per year.
The proportions responding at each price point are shown below.
Table 5: Proportions willing to pay an increase in Council Tax for
improvements
£5
Yes (asked £10)
No (asked £2)
£2
Yes
No
£10
Yes (asked maximum prepared to pay)
No
Maximum prepared to pay
£10
£10.01
£10.50
£11
£11.11
£12
£13
£15
£20
£25
£30
£40
£46
£50
£52
£60
£100
£200
£250
Holloway Road
%
75
25
Edgware Road
%
78
22
5
19
7
16
56
19
56
22
16
0
0
3
*
2
*
8
12
2
2
0
0
8
0
0
1
1
0
13
*
*
*
*
1
*
4
11
6
3
1
*
10
*
1
1
0
*
© Association for European Transport and contributors 2007
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Base
167
225
This data was used to calculate the maximum preparedness to pay. For
example a respondent who said ‘no’ to £2 increase was assumed to be
prepared to pay 0p, a respondent who said yes to £5 but no to £10 was
assumed to be prepared to £5 and a respondent who said yes to £10 was
asked the maximum he/she would be prepared to pay.
On this basis the average annual increase in Council Tax to pay for all the
improvements was £17.35 at Edgware Road and £14.78 at Holloway Road.
Journey Cost
The public transport users who paid fares were asked questions about their
willingness to pay increased public transport fares for the improvements they
had just seen in the stated preference.
There were three price points: 5p, 2p and 10p per public transport journey.
The proportions responding at each price point are shown below.
Table 6: Proportions willing to pay an increase in fares for
improvements
5p
Yes (asked 10p)
No (asked 2p)
2p
Yes
No
10p
Yes (asked maximum prepared to pay)
No
Maximum prepared to pay
10p
11p
12p
15p
20p
25p
26p
30p
40p
50p
£1
£1.10
£1.50
£1.60
£1.70
£2
£2.10
Base
Holloway Road
%
64
36
Edgware Road
%
51
49
8
28
11
38
47
17
34
17
0
8
0
5
16
1
0
2
0
9
4
0
0
0
0
0
0
222
0
8
1
2
8
0
0
1
0
7
2
0
1
0
1
0
0
210
The mean additional fare was 17p at Edgware Road and 18p at Holloway
Road.
© Association for European Transport and contributors 2007
13
Rent
The rent payers were asked questions about their willingness to pay
increased rent for the improvements they had just seen in the stated
preference.
There were three price points: 10p, 2p and 20p per week.
The proportions responding at each price point are shown below.
Table 7: Proportions willing to pay an increase in rent per week for
improvements
10p per week
Yes (asked 20p)
No (asked 2p)
2p per week
Yes
No
20p per week
Yes (asked maximum prepared to pay)
No
Maximum prepared to pay
21p
25p
30p
40p
50p
52p
60p
75p
80p
85p
90p
£1
£1.50
£1.60
£2
£3
£5
£6
£7
£10
£11
£12
£12.50
£15
£20
Base
Holloway Road
%
78
22
Edgware Road
%
73
27
5
17
10
16
55
23
54
19
6
3
4
3
10
0
0
0
0
0
0
10
0
0
2
2
3
0
0
4
1
0
0
2
3
5
6
5
2
5
0
1
0
0
0
0
10
1
0
1
0
5
0
0
5
1
0
0
0
4
226
220
This data was used to calculate the maximum preparedness to pay. The
average weekly increase in rent to pay for all the improvements was £2.02 at
Edgware Road and £1.90 at Holloway Road.
© Association for European Transport and contributors 2007
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Comparison of Payment Mechanisms
Table 8 shows a comparison of the three different payment mechanisms. It
should be borne in mind that different respondents answered different
payment mechanisms.
For public transport per trip figures were annualised by multiplying them by
the average number of public transport trips made per week by public
transport fare payers and then multiplying by 48 weeks.
The preparedness to pay increased rent or public transport fares for the
improvements are much higher than for Council Tax. This is probably largely
because the values were asked for in weekly amounts for rent (although the
annual amount was mentioned) and per trip for public transport users whereas
for the Council tax they were always asked in annual amounts.
Table 8: Comparison of payment mechanisms
Holloway Road
Edgware Road
Council Tax
£17.35
Annual amount
£14.78
225
Base
167
Rent
£2.02
£1.90
Weekly amount
£105.04
£98.80
Annual amount
220
226
Base
Public Transport Fares
17p
18p
Per trip
13.82
12.40
Weekly number of trips
£112.77
£107.14
Annual amount1
210
222
Base
1
the annual amount is based on 48 weeks (assuming 4 weeks holiday)
4.
WILLINGNESS TO PAY FOR IMPROVEMENTS TO THE PUBLIC REALM
4.1.
Transferability
Whether the results can be transferred between sites depends, in part, on
whether improvements were valued differently in different locations or vary by
user type. Significance tests were conducted to determine whether
preferences vary. The stated preference data for Holloway Road and Edgware
Road were re-run as additive models which gave a better impression of what
segmentations were significantly different. The results showed that:
•
The only coefficient which was significantly different between Edgware
Road and Holloway Road was ‘direct green man crossing’
•
There were no significant differences between residents and visitors for
Holloway Road and Edgware Roads
•
There were no significant differences between commuters and noncommuters.
© Association for European Transport and contributors 2007
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This suggests that results are transferable between high street locations in
London since it appears that respondents answered with their general high
street preferences.
4.2.
Choice of Payment Mechanism
As previously described, a transfer pricing approach was used to assess three
payment mechanisms.
The average willingness to pay for each is shown in Table 9.
Table 9: Willingness to pay by mechanism (average)
Council Tax
£16
392
Annual amount
Respondents
Public Transport
Fares
£110
432
Rent
£102
446
Clearly the council tax value is much lower than the results obtained for the
other two. To look more closely at an explanation for this, the distribution of
responses is shown in Figure 2.
Figure 2: Distribution of responses by payment mechanism
40%
35%
30%
25%
20%
15%
10%
5%
Rent
0%
Fares
£0-£5
£5 - £15
£15 - £25
£25-£50
Council Tax
£50-£100
Council Tax
£100 -£200
Fares
£200-£500
£500+
Rent
Between £5 and £100, the three payment mechanisms have similar
distributions. However, Figure 2 shows that there is a difference at the bottom
and a major difference at the top. At the bottom, the proportion of zero
valuations is higher for public transport fares than it is for either of the other
mechanisms (33% as opposed to 17%). At the top, fares and rent have a
higher proportion of values over £200 p.a (12% as opposed to 1%). Table 10
shows possible explanations for the differences.
© Association for European Transport and contributors 2007
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Table 10: Possible explanation for high/low values
Council
Tax
Fares
Rent
4.3.
Possibly Low
The qualitative research showed
many people objected to higher
council tax because of perceived
inefficiency.
Possibly High
n/a
Respondents may find it difficult to
value annual measures.
The qualitative research showed
many people objected to higher fares.
The % of zero valuations may be
above that found for council tax/rent if
respondents do not see a direct link
between fares and urban realm
improvements.
People may find it difficult to link rent
to street improvements
Respondents answered on a per trip
basis and were not presented with
annualised figures.
The correlation between rent and
council tax show a number of
respondents mistakenly gave annual
figures when prompted for a weekly
maximum.
Annual Willingness to Pay
In order to test the most appropriate figure for annual willingness to pay from
the three mechanisms, sensitivity tests were carried out by:
•
•
•
•
removing the top and bottom 1%, 2.5%, 5% and 10% of answers
removing the additional zero valuations associated with the fares
mechanism
capping values at £100 p.a
re-coding selected rent values to an annualised measure.
Table 11: Summary of sensitivity tests
Test
Base
Top/tail 1%
Top/tail 2.5%
Top/tail 5.0%
Top/tail 10%
Cap values at £100 p.a
17% zero valuation for farebox
17% zero valuation for farebox & 5% cut from top
17% zero valuation for farebox & £100 cap
Recoding annual rent values with CT/£100 cap
Council Tax
(£)
16.26
14.87
14.06
13.43
11.95
15.62
-
Farebox
(£)
108.66
80.96
68.26
55.76
42.00
37.38
130.76
64.36
44.98
-
Rent
(£)
101.19
91.37
77.19
59.31
34.14
29.10
23.06
Each mechanism for assessing willingness to pay has advantages and
disadvantages. The results do not suggest clear reasons for disregarding any
mechanism. Since the range itself may be valuable in certain cases, it would
appear useful to collect values for more than one measure. With this in mind,
© Association for European Transport and contributors 2007
17
the value associated with improving the public realm is best expressed as a
range. The results suggest this range lies between £12 and £130. Within this,
a most likely range is shown in Table 12.
Table 12: Most likely range
Test
Top/tail 5.0%
Cap values at £100 p.a
Council Tax
(£)
13.43
15.62
Farebox
(£)
55.76
37.38
Rent
(£)
59.31
29.10
This suggests that £13 and £59 can provide low and high values for appraisal.
If a single number is required, a simple average of these (£35) is a reasonable
approach. However, given the need for comparability with other TfL
appraisals, public transport fares provide, perhaps, the most useful indicator.
As a result, we take £45 as the value used for willingness to pay valuation. By
applying both a £100 cap and a 17% proportion valuing improvements at zero,
this is a figure determined from the most reliable data obtained for fares.
5.
EVALUATING THE PUBLIC REALM FOR BUSINESS CASES
5.1.
Outline
The following describes how the values obtained for willingness to pay for
improvements to the urban realm have been developed into an evaluation
mechanism. It is split as follows:
•
•
•
•
5.2.
The meaning of the overall valuation
Values by element
Values by time spent
Values in an evaluation framework.
The Meaning of the Overall Valuation
In the transfer pricing questions, it was not made explicitly clear to
respondents that the willingness to pay for improvements was for
Edgware/Holloway Road alone. The rest of the data collected provides an
insight into what this covers. It appears to suggest that respondents valued:
•
Improvements between the lowest and highest standards presented in
the show material (rather than between base conditions on site and the
highest standard)
•
Improvements for high streets in general (rather than just the high
street they were on).
If the value placed by respondents was related to the starting condition on the
road then one would anticipate a positive correlation between start condition
and willingness to pay. In fact, this is not the case. Figure 3 shows that the
relationship appears to be either nil or normally distributed. As a result, it
© Association for European Transport and contributors 2007
18
appears that given the phrasing of the question, and the lack of significant
difference between values for Edgware Road and Holloway Road, willingness
to pay values represent the change from the show material with the worst
condition to that with the best. Since the worst show material presented was,
typically, worse than both Holloway Road or Edgware Road, this is a
conservative assumption that reduces the values applied in appraisals.
Figure 3: Base condition against willingness to pay
Willingness to pay
'
750
500
250
0
0
5
10
15
20
25
30
Assessment of base conditions
The payment mechanism suggested is public transport fares. With this
mechanism, it appears likely that residents provided values for both origin and
destination of that journey rather than something specific to Edgware Road.
This hypothesis is backed up by the lack of significant differences between
preferences among the resident and visitor groups.
Given the lack of correlation between base conditions and willingness to pay
as well as a pricing mechanism that involves two places, it appears that
respondents were valuing improvements over a larger area than that defined
by the study limits. We suggest that respondents answered with values that
cover all of their walks on high streets for an entire year. Since this means that
the values specified cover a wider area, it is a conservative assumption that
significantly reduces the values applied.
5.3.
Values by Element
In order to place values on elements, it was important to ensure that the both
the start and end conditions were taken into account. In this way, the value
applied was for the change in condition. With up to three levels within each
category, this results in levels defined as low, medium or high are shown in
Table 13.
© Association for European Transport and contributors 2007
19
Table 13: Stated preference elements categories
Stated Preference
Element
Number of people
in daylight
Kerbs
View of the street
Low
Very crowded so that
walking pace is badly
affected
Step at kerb
Blocked view of street
Crossing the road
No green man crossing
Signs to public
transport and
attractions
Street lighting
Street (nearly) deserted
after dark
Pavement cracked and
uneven
Vehicles park on
pavement
Cyclists ride on
pavement
Plants and public
art
No plants or public art
Physical intrusion
of traffic
Graffiti and flyposting
Litter
Sloped kerb
Clear view of
street
Green man
crossing in
stages
-
Very poor lighting after
dark
No seating areas
Traffic flow prevents
crossing and there are
high levels of noise
Significant graffiti/
flyposting
Significant litter and
chewing gum
High
Street (nearly) deserted
-
No signage
Number of people
after dark
Pavement
condition
Vehicles on the
pavement
Cycles on the
pavement
Seating
Medium
Reasonably
bright, patchy
lighting after dark
A few people
around after dark
Pavement
cracked but even
Plants alongside
street
Generally free
from litter and
chewing gum
Completely flat crossing
Mainly clear view of street
Direct green man
crossing
Local area maps,
information boards and
signed routes
Good, bright, even
lighting after dark
A lot of people around
after dark
Pavement has no cracks
and is even
Vehicles do not park on
pavement
Cyclists allocated lane/
own space for riding on
pavement
Plants alongside street
and public art in well
chosen locations
Seating areas at well
chosen locations
Traffic flow is safe to
cross and there is little or
no noise
Generally free from
graffiti/flyposting
Generally free from litter
and no chewing gum
The coefficients for each category in the table above provided the basis for
splitting the values by element. Where mid-values exist, these were converted
to money values by linear interpolation. Based on this, the valuation by
element is shown in Table 14.
© Association for European Transport and contributors 2007
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Table 14: Stated preference valuation by element and level
Stated Preference Element
Number of people in daylight
Kerbs
View of the street
Crossing the road
Signs to public transport and attractions
Street lighting
Number of people after dark
Pavement condition
Vehicles on the pavement
Cycles on the pavement
Plants and public art
Seating
Physical intrusion of traffic
Graffiti and fly-posting
Litter
5.4.
Low
(£ pa)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Medium
(£ pa)
2.40
1.89
3.40
2.99
0.77
3.37
1.65
2.29
High
(£ pa)
1.11
2.79
2.64
4.34
3.11
4.94
1.36
4.07
4.54
2.81
2.23
3.07
2.14
1.93
3.90
Values by Time Spent
Since it appeared that respondents placed values for annual journeys in high
streets in general, it was important to determine how much time was spent in
high streets. The responses provide data on:
•
•
•
•
Frequency respondents walk along the high street in an average week
The type of use of the high street (National Travel Survey definitions)
Resident/visitor split
Length of time spent by journey purpose (commuting/shopping/leisure).
Through breaking usage down into types, and capping answers that included
time in shops as walking time, this information was used to estimate total time
spent along high streets in a year. This came to about 80 hours per year (1
hour 40 minutes per week).
To obtain values for improvements, this figure wasused to convert the annual
values into pence per minute spent on improved walkway. These values are
shown in Table 15.
© Association for European Transport and contributors 2007
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Table 15: Values by time spent
Stated Preference Element
Number of people in daylight
Kerbs
View of the street
Crossing the road
Signs to public transport and attractions
Street lighting
Number of people after dark
Pavement condition
Vehicles on the pavement /
Cycles on the pavement
Plants and public art
Seating
Physical intrusion of traffic
Graffiti and fly-posting
Litter
5.5.
Low
(pence per
min)
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Medium
(pence per
min)
0.05
0.04
0.07
0.06
0.02
0.07
0.03
0.05
High
(pence per
min)
0.02
0.06
0.06
0.09
0.07
0.10
0.03
0.09
0.10
0.06
0.05
0.06
0.04
0.04
0.08
Values in an Evaluation Framework
It is possible to develop business cases based entirely on the figures provided
above. The fifteen categories provide a means of assessment that can be
applied to any number of schemes in London. However, in order to more
accurately assess the improvement to the public realm, it is better to assess
changes within a framework that:
•
•
•
•
•
Accounts for the interaction of different elements
Covers as wide a range of scheme types as possible
Offers consistency in measurement of the extent of improvements
Ensures that small changes are not exaggerated or ignored
Covers conditions better than the highest show material and worse than
the lowest show material.
PERS provides a framework that can be used to achieve all of these. PERS is
an audit tool developed by TRL and which is already in use at TfL to assess
the walking environment. PERS can assess infrastructure provision of links
and public spaces (as well as crossings, routes, public transport waiting areas
and interchange spaces). For links and public spaces, there are 14 and 6
characteristics respectively that are scored. For example, the characteristics
of links include ‘effective width’, ‘dropped kerbs’ and ‘permeability’. In a PERS
audit, a scorecard, detailed instruction manual and a series of prompts are
used to score these characteristics on a 7 point scale between -3 and +3. This
helps auditors to provide a consistent measure of the walking environment
that can be used to compare different locations. The first of two scorecards
used for assessing links is shown in Figure 4.
© Association for European Transport and contributors 2007
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Figure 4: Example PERS Scorecard
© Association for European Transport and contributors 2007
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The full list of characteristics for both links and public spaces is shown in
Table 16.
Table 16: PERS Characteristics for links and public spaces
Links
Effective width
Dropped kerbs
Gradient
Obstructions
Permeability
Legibility
Lighting
Tactile information
Colour contrast
Personal security
Surface quality
User conflict
Quality of environment
Maintenance
Public spaces
Moving in the space
Interpreting the space
Personal safety
Feeling comfortable
Sense of place
Opportunity for activity
Since it is not possible to portray many of these characteristics graphically, it
was necessary to use a proxy for these in the stated preference exercise. The
fifteen elements assessed were chosen specifically for that purpose. They
provide a cross-section of the walking environment that can best act as a
proxy for the characteristics defined in PERS for both links and public spaces.
Since some of the stated preference elements feature in more than one PERS
characteristic (for example ‘pavement condition’ in the stated preference
affects both ‘quality of the environment’ and ‘surface quality’ in PERS), and
others are not used as a proxy at all (for example ‘colour contrast’ has no
proxy among the SP elements), Table 17 and Table 18 show how elements
have been divided into PERS to ensure that appraisals do not suffer from
double counting.
Table 17: Splitting SP elements into PERS for links
Characteristic in PERS for
Links
Effective width
Dropped kerbs/Gradient
Obstructions
Permeability
Legibility
Lighting
Personal security
Surface quality
User conflict
Quality of environment
Maintenance
Percentage
100
100
100
50
100
100
50
50
100
50
50
100
100
50
100
100
50
50
100
Stated Preference Element
Number of people in daylight*
Kerbs
View of the street
Physical intrusion of traffic
Crossing the road
Signs to PT and attractions
Street lighting
Street lighting
Number of people after dark
Graffiti and fly-posting
Pavement condition
Vehicles on the pavement
Cycles on the pavement
Pavement condition
Plants and public art
Seating
Physical intrusion of traffic
Graffiti and fly-posting
Litter
© Association for European Transport and contributors 2007
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* Issues with the ordering of the levels prevented us obtaining significant results for the highest level in
this category. As a result, values are an underestimate of the journey ambience benefits.
Table 18: Splitting SP elements into PERS for public spaces
Characteristic in PERS for
Public Spaces
Moving in the space
Interpreting the space
Personal safety
Feeling comfortable
Sense of place
Opportunity for activity
Percentage
100
100
100
100
100
100
100
100
100
100
100
100
100
100
Stated Preference Element
Pavement condition
Kerbs
Number of people in daylight
Signs to PT and attractions
Number of people after dark
Street lighting
Graffiti and fly-posting
Litter
Seating
Physical intrusion of traffic
Plants and public art
Crossing the road
Vehicles on the pavement
Cycles on the pavement
With these splits and the monetary values developed for each of the stated
preference elements, it is possible to ascertain a value for each of the PERS
characteristics. That value can then be related to PERS scores by using
PERS to assess the show material graphics. The scores for the show material
graphics can then be interpolated to provide a value for the full scale of scores
for each characteristic. The results from this are shown in Table 19 and Table
20.
Table 19: Journey ambience benefits for improvements to links (pence
per person per minute)
Characteristic
in PERS
Effective width
Dropped
kerbs/ gradient
Obstructions
Permeability
Legibility
Lighting
Personal
security
Surface quality
User Conflict
Quality of
environment
Maintenance
TfL Design Principle
Create convenient connections
Create convenient connections
/ Get the detail right
Create convenient connections
Create clear and easy to
understand routes and spaces
Create clear and easy to
understand routes and spaces
Get the detail right
Create active and engaging
spaces
Get the detail right
Create streets and spaces for
everyone
-3
-2
-1
0
1
2
3
0.00 0.00 0.01 0.01 0.02 0.02 0.03
Get the detail right
0.00 0.06 0.12 0.18 0.21 0.24 0.27
Get the detail right
0.00 0.02 0.04 0.06 0.08 0.09 0.10
0.00 0.01 0.02 0.04 0.04 0.04 0.04
0.00 0.01 0.01 0.02 0.02 0.03 0.03
0.00 0.03 0.06 0.10 0.11 0.12 0.13
0.00 0.01 0.02 0.03 0.04 0.05 0.06
0.00 0.02 0.04 0.05 0.06 0.07 0.08
0.00 0.03 0.06 0.09 0.11 0.13 0.15
0.00 0.03 0.05 0.08 0.10 0.11 0.11
0.00 0.03 0.05 0.08 0.10 0.11 0.13
© Association for European Transport and contributors 2007
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Table 20: Journey ambience benefits for improvements to public spaces
(pence per person per minute)
Characteristic
in PERS
Moving in the
space
Interpreting the
space
Personal
safety
Feeling
comfortable
Sense of place
Opportunity for
activity
TfL Design Principle
Create convenient connections
Create clear and easy to
understand routes and spaces
Create streets and spaces for
everyone / Create active and
engaging spaces
Create streets and spaces for
everyone
Create active and engaging
space / Get the detail right
Create active and engaging
spaces
-3
-2
-1
0
1
2
3
0.00 0.04 0.09 0.13 0.15 0.16 0.18
0.00 0.01 0.02 0.03 0.04 0.05 0.06
0.00 0.04 0.08 0.13 0.17 0.21 0.25
0.00 0.02 0.05 0.07 0.09 0.12 0.14
0.00 0.01 0.03 0.04 0.05 0.05 0.06
0.00 0.07 0.14 0.22 0.25 0.27 0.30
With a PERS audit carried out prior to bidding for funds and an estimate of
post-implementation scores conducted for the scheme designs, these tables
provide valuation of the improvement (measured in pence per person per
minute walked in that environment). Measuring improvements in this way
ensures:
•
•
•
•
consistency among appraisals
inclusion of a wide variety of scheme types
that small differences are factored in (using the seven point scale)
that appraisals take a holistic view of the walking environment taking into
account interactions between measures.
This clearly represents a major step forward in bringing a rigorous approach to
the appraisal of very soft public realm improvements. It is hoped and expected
that this will lead to a better allocation of funds and better design of schemes.
1
Fruin pedestrian density calculations (in persons per metre per minute) are
established measure of crowding (Fruin, J. J., Pedestrian Planning and
Design, 1971)
© Association for European Transport and contributors 2007
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