Post on 01-Jan-2016
1
Preferred citation style
Axhausen, K.W. (2001) Social networks and travel behaviour, ESRC Workshop „Mobile network seminar series - Seminar 2: New communication technologies and transportation systems“, Lucy Cavendish College, Cambridge, February 2002.
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A word of warning
An engineer talking about daily life and its underlying social structures puts himself at risk.
I am happy to take the risk and look forward to the critique and comments, as
• We need to underpin our travel behaviour models with a better understanding of the social structures of daily life
and, as
• We implicitly forecast/speculate about them when we predict travel behaviour over long time horizons, anyway
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A look back: Productivity growth since 1000 (W Europe)G
alor
und
Wei
l (20
00)
0.00
0.50
1.00
1.50
2.00
2.50
3.00
1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000
Year
Gro
wth
rat
e [%
/yea
r]
ProductivityPopulation
5
A look back: pkm/day since 1850 (France)
0
10
20
30
40
50
1840 1860 1880 1900 1920 1940 1960 1980
Year
km/P
erso
n an
d da
y
Motorised individual modesPublic transportSlow modes
Gru
ber
(199
8)
6
A look back: GDP, Car and telephone ownership (CH)
0
250
500
750
1890 1910 1930 1950 1970 1990
Year
Num
ber/
1000
res
iden
ts
0
200
400
600
GD
P (
1913
= 1
00)
Telephone Mobile phone
Cars Internet userGDP
7
A look back: Average consumption of housing (CH)
0
15
30
45
60
1950 1960 1970 1980 1990
Year
Gro
ss a
rea/
hea
d [m
2]
CentresAgglomerationRegional centresRural villagesMountain villagesSwitzerland
Rum
ley
(198
4); K
elle
r
8
A look back: Household size (CH)S
iege
ntha
ler
and
Ritz
man
n-B
licke
nsto
rfer
(19
96)
0
1
2
3
4
5
6
1850 1870 1890 1910 1930 1950 1970 1990
Year
Mea
n ho
useh
old
size
[]
Central SwitzerlandAlpine cantonsNE - SwitzerlandNW - SwitzerlandRomandieSwitzerland
9
Look back: Distribution of personal time (UK)
0%
20%
40%
60%
80%
100%
1860 1880 1900 1920 1940 1960 1980 2000
Year
Life
time
shar
e [%
]
RetirementLeisure and otherWorkHigher educationChildhood and schooling
Gru
ber
(199
8)
10
Summary for the look back
Extraordinary income streams have been created and are consumed (in part) as
• Travel (Speed)• More (and dispersed) housing • Long-distance communication• Longer lives with less work
• Independence/Isolation
11
Daily life: Trip purposes (Uppsala 1971/Karlsruhe 1999)S
chlic
h an
d S
chön
feld
er
0 10 20 30 40 50
Other
Work-related business
Pick up/drop off
Long-term shopping
Education
Private business
Daily shopping
Work
Leisure
Return home
Share of all trips [%]
Uppsala (weighted)Karlsruhe Mobidrive
12
Daily life: Leisure (Uppsala 1971/Karlsruhe 1999)S
chlic
h an
d S
chön
feld
er
0 10 20 30 40
Meeting relatives
Window Shopping
Excursion: Culture
Club meeting
Other
Going for a walk and hiking
Active sports
Going out in the evening
Meeting friends
Share of all leisure trips [%]
Uppsala (weighted)
Karlsruhe Mobidrive
15
Daily life: Local activity space of a car (Borlänge 2001)
Locations visited during a 3 month period by one carS
chön
feld
er
16
Daily life: Example activity spaces (Karlsruhe 1999)S
chön
feld
er
Ellipses cover the 95% confidence intervals of the locations visited
17
Summary: Daily life
Households are self-selected/trapped into the vector of
• Home location• Work/school locations• Mobility tools
Dominant shares of
• Leisure trips• Household maintenance trips
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Social networks: Draft categorisation
• Family• Friends• Hobby (Animal care)• Sport• Civic engagements• Church
• Neighbours
• School/education• Work (one or multiple networks ?)• (Military/Civilian service)
• Service providers
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Social networks: Possible transport questions
• Physical spatial-temporal coherence/overlap (constraints)
• Replacement of physical and telecommunication-based contact
• Interaction frequency and spatial reach
• Interaction and information/knowledge transfer
23
Social networks: Possible sociological questions
• Openness/replacement dynamics of the membership• Structure and definition of the network boundaries• Revival of contact/repair of links
• Shared skill/learning• Transfer/transmission of reputation• Transfer of resources/social capital
• Spatial and social reach (“6 degrees of separation” ?)
• (Time/money/social capital) Cost of maintenance
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Social networks: Hypotheses
1. Local spatial-temporal coherence is lower than 1950
Why ?• The unity of work, residence and „Sozialmileu“ has been
broken for most people (e.g. long-distance commuting)
• Educational/employment paths are less uniform (in space)
• Mass customisation in travel (car), consumption and leisure (channel flood in entertainment)
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Social networks: Hypotheses
2. The number of the current members is larger than in the past
Why ?• Money costs of contact have been dramatically reduced
(telephone, email, letter/xeroxing)• Easier projection of self (email, xeroxing) allows more social
grooming (Dunbar’s about 100) • Time/money costs of in-person contact with spatially distant
contacts have become – relatively – affordable (i.e. cheap long-distance travel)
2* Statements about the contact intensity distributions are difficult, as the increase in leisure time might balance the larger number of members
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Social networks: Hypotheses
3. Time costs of network maintenance are larger than in the past
Why ?• Less chance of chance encounters• Lower local spatial network densities • Less opportunity to use proxies for messaging• Higher search costs (locating the person) (but for email,
mobiles, answering machines)
• Higher time costs to get to most members of the net• Longer catching-up times
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Social networks: Externalities
• Stronger selectivity ?
• Less local inclusion ? (More commercial/institutional personal services ?)
• Less local generalised trust ? (feeling of safety and reliability)
• Car/paid travel dependence ?
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(Concurrent) Spatial developments
Economically
• Increased specialisation of locations (regionally, internationally)
• Increased firm size in services and production• Increased market sizes at all scales
Urban
• Increased scales• Lower local densities
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Spatial developments: Externalities
• Car/paid travel dependence ?
• Transport emissions (Noise, CO2, HC etc.)
• Loss of the common pedestrian environment• Arrival of the themed pedestrian environment
• Spatial segregation (locally, regionally)
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Required networking tools
• Car (budget for taxi)• Budget for long-distance travel• (Mobile) phone • Location-free contact point (answering service, email, web-
site)
• Time to manage the above
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Expenditure for those tools (CH)
0
10
20
30
40
50
1840 1860 1880 1900 1920 1940 1960 1980 2000
Year
Sh
are
of d
isp
osa
ble
inco
me
[%]
Food
Housing
Education & leisure
Transport andcommunications
Wid
mer
(20
01)
19
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What now ?
Transport:• Better management of resources (demand-responsive
operation)• Demand-responsive pricing • Pricing of externalities
Socially:• Better time organisation
• Common scheduling tools• Reorganisation of working time
• Demand-responsive service delivery
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What now ?
Spatially:
• Better pricing of externalities• Growth boundaries• Rescaling of the environments• Rebuilding the buildings/infrastructures of the post-war
period
• (Subsidised) local service points/local shopping facilities
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Literature
Axhausen, K.W. (2000) Geographies of somewhere: A review of urban literature, Urban Studies, 37 (10) 1849-1864
Congress for New Urbanism (2000) Charter of the New Urbanism: Region; Neighborhood, District and Corridor; Block, Street and Building, McGraw Hill, New York
Fishman, R. (1992) Urban Utopias in the Twentieth Century: Ebenezer Howard, Frank Lloyd Wright, Le Corbusier, MIT Press, Cambridge.
Galor, O. and D.N. Weil (2000) Population, technology, and growth: From Malthusian stagnation to the demographic transition and beyond, American Economic Review, 90 (4) 806-828.
Gruber, A. (1998) Technology and Global Change, Cambridge University Press, Cambridge.
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Literature
Jacobs, A.B. (1993) Great Streets, MIT Press, Cambridge.
Putnam, R.D. (1999) Bowling Alone: The collapse and revival of American community, Schuster and Schuster, New York.
Rumley, P.A. (1984) Amenagement du territoire et utlisation du sol, Dissertation, ORL, ETH Zürich, Zürich.
Siegenthaler, HJ. and H. Ritzmann-Blickenstorfer (eds.) (1996) Historische Statistik der Schweiz, Chronos, Zürich
Simma, A. and K.W. Axhausen (Im Druck) Structures of commitment and mode use: A comparison of Switzerland, Germany and Great Britain, Transport Policy.
Widmer, J.P. (2001) Ausgewählte Schweizer Zeitreihen zur Verkehrsentwicklung, Materialien zur Vorlesung Verkehrsplanung, 1.02, IVT, ETH Zürich