1

Preferred citation style

Axhausen, K.W. (2005) Activity spaces, biographies, social networks and their welfare gains and externalities: Some hypothesis and empirical results, PROCESSUS Colloquium, Toronto, June 2005.

Activity spaces, biographies, social networks and their welfare gains and externalities: Some hypothesis and empirical results

KW Axhausen

IVTETHZürich

March 2005

3

Time-scaled “road”-Switzerland (1950 and 2000)S

cher

er, 2

004

4

Markets: Price deflation for cars

0

200

400

600

800

1000

1200

1400

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Jahr

Qu

alitä

tsbe

rein

igte

r P

reis

ind

ex

(2

004

= 1

00)

[%]

Frei, 2004

Raff und Trajtenberg, 1990

Fre

i, 20

05

5

Markets: Price deflation for telecommunicationN

ach

FC

C (

2001

)

0

250

500

750

1000

1250

1500

1750

2000

1930 1940 1950 1960 1970 1980 1990 2000

Year

Inde

x [1

995

= 1

00]

US International and interstate averagerevenue per minute

6

Example of a local activity space

Female, 24

Full time

Single

216 trips / 6 weeks

12000761Sch

önfe

lder

7

Example of a social network geography

Female, 28,

4 moves,

Public

transport user

Ohn

mac

ht, 2

004

8

Example: Commuter sheds of the 10 largest Swiss townsN

ach

Bot

te, 2

003

9

Size of activity spaces: A hypothesis

Wages

Fleetcomfort

Housingconsumption

vtts et al.

Activities

Specialisation

Activity space

k

vkm

pkmTours ++

+

++

++

++

++

+

+

-

- -

+

-

Energy costs

+

+-

Elasticity > 0 Elasticity < 0

k: personal short term generalisedcosts of travel

+

-

Migration+

+

10

Impact of biographies: Hypotheses

Personalworld

Biography

Projects

Learning

Act

ivity

reper

toireM

ental m

ap

11

Definition of a social network

The topology of a social network describes

• Which person/firm (node) is linked to which other persons/firms

• By contacts (links) of a certain quality (impedance or cost)

Closeness ~ 1/Impedance

12

Travel and social networks

Maintenance of the network requires:

• Face to face contacts• Balanced by other forms of contacts

• Travel ~ Physical spread of the contacts

• Trade-off between loosing contacts and “social” capital and investing in new contacts closer to home

13

Contact costs: Distance and meeting frequency

Meeting frequency

Up to more than year

Once a month

More than monthly

Once a w eek

More than w eekly

Me

dia

n d

ista

nc

e b

etw

ee

n h

om

es

50

40

30

20

10

0

Relationsship

Friend

"Kollege"

Acquaintance

Children

Parents

Siblings

Other family

14

Contact frequencies: E-Mail messages to kwa

15

Hypotheses

Professionalactivity space

MigrationkMessagecosts

Numberof networks

Networkgeography

Networkoverlap

Left skew ofintensity distribution

Personal activity space

Local anomie

+-

Elasticity > 0 Elasticity < 0

+ ++

+

+

+

--

- - -

- - -

-

16

Expected impacts: Spare versus dense networks

17

Expected impacts: Spare versus dense networks

Scales could be different !

18

Expected impacts: Improved welfare

The social networks should be more homogeneous and therefore more productive for their members

But, the selectivity excludes the „less attractive“ persons who are disadvantaged through a reduced ability to travel or a reduced ability to participate in activities

But, the dependence on commercial or state-provided services for “care” increases

19

Research issues

• Measurement of the activity spaces (geographies, markets)• Estimate of historical activity spaces ...

• Taste differences in network form and geography• Social/cultural preferences for network form and geography

• Stability of the geographies under pressure• Elasticities to policy (or environmental) change• Time until trend change

20

Policy questions

• Is „happiness“ still growing ?

• How large are the social externalities ?

• How stable is the overall system under pressure ?

21

The hypotheses summarized

Wages

Fleetcomfort

Housingconsumption

vtts et al.

Activities

Specialisation

k

vkm

pkmTours ++

+

++

++

++

++

+

+

-

- -

+

-Energy costs

+

+-

Elasticity > 0 Elasticity < 0

+

-

Migration+

+

Professional andpersonal activity space

NetworkgeographyNumber

of networks

Networkoverlap

Local anomie

-

+

+-

- -

--

22

Literature and references

Axhausen, K.W. (2000) Geographies of somewhere: A review of urban literature, Urban Studies, 37 (10) 1849-1864.

Axhausen, K.W. (2003) Social networks and travel: Some hypotheses, Arbeitsberichte Verkehr- und Raumplanung, 197, Institut für Verkehrsplanung und Transportsysteme (IVT), ETH Zürich, Zürich.

Axhausen, K.W., S. Beige und M. Bernard (2004) Perspektiven des Schweizerischen Verkehrs bis 2030: Module M04 und M05 Besitz von Mobilitätswerkzeugen – Fahrleistungen/Betriebsleistungen und Verkehrsleistungen, Bericht an das ARE, IVT, ETH Zürich, Zürich.

Axhausen, K.W. und P. Fröhlich (2004) Public investment and accessibility change, in P. Marti und A. Müller (Hrsg.) Festschrift Schalcher, vdf, Zürich.

Botte, M. (2003) Strukturen des Pendelns in der Schweiz, Diplomarbeit, Fakultät für Bauingenieurwesen, TU Dresden, August 2003.

FCC (2001) Long distance telecommunication industry, FCC, Washington, D.C.Gätzi, M. (2004) Raumstruktur und Erreichbarkeit, Diplomarbeit, IVT, ETH Zürich,

Zürich.Galor, O. und D.N. Weil (2000) Population, technology, and growth: From

Malthusian stagnation to the demographic transition and beyond, American Economic Review, 90 (4) 806-828.

23

Literature and references

Gruber, A. (1998) Technology and Global Change, Cambridge University Press, Cambridge.

Putnam, R.D. (1999) Bowling Alone: The collapse and revival of American community, Schuster and Schuster, New York.

Rhode, P.W. und K.S. Strumpf (2003) Assessing the importance of Tiebout sorting: Local heterogeneity from 1850 to 1990, American Economic Review, 93 (5) 1648-1677.

Rumley, P.A. (1984) Amenagement du territoire et utlisation du sol, Dissertation, ORL, ETH Zürich, Zürich.

Siegenthaler, HJ. und H. Ritzmann-Blickenstorfer (eds.) (1996) Historische Statistik der Schweiz, Chronos, Zürich.

Srivastava G. und S. Schönfelder (2003) On the temporal variation of human activity spaces, Arbeitsberichte Verkehr- und Raumplanung, 196, Institut für Verkehrsplanung und Transportsysteme (IVT), ETH Zürich, Zürich.

Tschopp, M., R. Sieber, P. Keller und K.W. Axhausen (2003) Demographie und Raum in der Schweiz, DISP, 153, 25-32.

24

Social networks: Hypotheses

[1] The size of the social network geography is inversely proportional to the generalised costs of travel and communication

[2] The number of contacts individuals maintain is inversely proportional to the generalised costs of travel and communication

[3] The probability of being linked to a member of one’s network through multiple networks increases with the spatial density of one’s contacts

[4] The distribution of effort on non-household members will become more left skewed as the spatial social network tightness decreases

[5] The knowledge about the contacts of contacts in a social network is proportional to the generalised costs of travel and communication

25

Social networks: Hypotheses (2)

[6] The activity space of an individual is proportional to its social network geography

[7a] The size of the local activity space of an individual stabilises after an initial exploration.

[7b] The size of the total activity space will grow in line with the growth of social network geographies.

[8] The reliance on commercial or publicly funded personal services increases proportionally with the geography of social networks

[9] The welfare of the individuals should increase inversely proportional to the generalised costs of travel

26

Share of joint travel (2003 Thurgau)

Short vacation

Excursion: nature

Other

Excursion: culture

Meeting friends

Further education (leisure)

Garden/ cottage

Voluntary work

Disco, pub, restaurant, cinema

Meeting relatives/family

Window shopping

Pick up/drop off/attendance

Group/club meeting

Family duty

Cemetery

Active sports

Education

Long-term shopping

Walk or stroll

Daily shopping

Private business

Private business (doctor,...

Work

3.02.52.01.51.00.50.0

Mean

Dog travelling along

Other persons travelling along

Household members travelling along

27

Contact intensities: E-Mail messages to kwa