Juan Antonio Carrasco
Associate Professor
Transportation Section, Department of Civil
Engineering, Faculty of Engineering, Universidad de Concepción
Telephone (Office): +56 41 220-3603 Department of Civil Engineering, |
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Resume (adobe
acrobat document)
Research projects, grants, and contracts
Doctor of Philosophy, Transport Engineering and Planning
University of Toronto, Department of Civil Engineering, Transportation
Engineering and Planning, 2006
Thesis: Social Activity-Travel Behaviour: A Personal Networks Approach
[Eric Pas Dissertation Prize (Honourable
Mention), awarded by the International
Association for Travel Behaviour Research to the best doctoral
dissertations on travel behaviour research in the year 2006] (Supervisor: Eric J. Miller, Co-supervisor: Barry Wellman)
Master in Engineering Science,
Transport Engineering
Pontificia
Universidad Católica de Chile, Departamento de Ingeniería de Transporte, Facultad de Ingeniería, 2001
Thesis: ‘Discrete Choice with
Correlated Homoskedastic Alternatives: The Nested
Logit Model in Depth’ (Supervisor: Juan de Dios Ortúzar)
Pontificia
Universidad Católica de Chile, Departamento de Ingeniería de Transporte, Facultad de Ingeniería, 2001
Pontificia
Universidad Católica de Chile, Departamento de Ingeniería de Transporte, Facultad de Ingeniería, 1999
Social networks and activity-travel behaviour
Social exclusion and accessibility issues
Information and communication technologies
(ICTs) and travel behaviour
Integrated land use models
Use and estimation of discrete choice and
statistical models applied to travel demand analysis
Relationship between urban form and travel
decisions
RESEARCH PROJECTS, GRANTS AND CONTRACTS
“Understanding the
relationship between people's mobility and food patterns, and the role of
attitudes and social networks,” (2017-2020) Chilean National Fund of Science
and Technology, FONDECYT (project No 1171113). Total budget: US $260,000 (PI).
“Understanding
mobility strategies to perform daily activity-travel in two Chilean cities,”
(2014-2017) Chilean National Fund of Science and Technology, FONDECYT (project No
1140519). Total budget: US $80,000 (PI).
“Center for
Sustainable Urban Development (CEDEUS),” Fondo de Financiamiento de Centros de Excelencia en Investigación
(Fund for Advanced Research in Priority Areas, Centers of Excellence FONDAP),
Chilean National Commission for Science and Technology, CONICYT (project
15110020). Total budget: US$7,500,000 (PI). www.cedeus.cl More info (in Spanish)
“Plataforma Tecnológica para la Gestión Integral del Sistema de
Transporte en la Región del Bío Bío,”
(Technological Platform for Comprehensive Transport System Management in the Bio Bio
Region), Fondo de Innovación Tecnológica de la Region del Biobio (Fund for Technological
Innovation, Biobio Region), Innova Biobio (project ibb-11-PCS2-1116). Total budget: US
$250,000 (co-PI). More info (in Spanish)
“TranSENDaNC
Transport and Social Exclusion: New Directions and National Comparisons”
(2012-2014), Marie Curie Actions - International Research Staff Exchange Scheme
(IRSES), FP7-PEOPLE-2011, European Union, with Oxford University and Ghent
University (project 294963). Total budget: €88,200 (PI). More info.
“Understanding the
link between transport and social exclusion in the Chilean context: An
assessment through quantitative indicators” (2011-2013) Chilean National Fund
of Science and Technology, FONDECYT (project No 1110920). Total
budget: US $120,000 (PI). More
info.
“Instituto
de Sistemas Complejos de la
Ingeniería y Tecnología”
(Institute of Complex Systems of Engineering and Technology) (2009-2014), Chilean
Research, Science and Technology Council (CONCYT), Programa
de Financiamiento Basal para Centros
de Excelencia, FBO-16. Direct budget: US $52,000
(researcher member). More info.
“La
experiencia urbana cotidiana en Concepción: Una exploración por los usos,
imaginarios y redes sociales en el Eje Bicentenario” (The
daily urban experience in Concepción: An exploration about the use, images, and social networks in a main avenue in the city)
(2009-2011) Proyecto DIUC Ciencias Sociales, 209.173.038-1FI (Internal Social Sciences Research Fund, Universidad de
Concepción) (co-PI).
“Social networks,
mobility, and accessibility: Unravelling the social dimension of travel
behaviour in a middle size city” (2007-2010) Chilean National Fund of Science
and Technology, FONDECYT (project No 11070075). Total budget: US $60,000 (PI). More
info.
“Graduate Students'
Exchange Program (GSEP) Competition” (2008, 2011, 2017), Canadian Commonwealth Scholarship Program (CCSP) Government of Canada
Awards (GCA), and Emerging Leaders in
America Program (ELAP), Government of Canada. US $55,000. Exchange program
that has financed six graduate students to perform research in Canada for four
months as part of joint research with Professor Antonio Páez (McMaster
University).
CURRENT AND RECENT PROFFESIONAL ACTIVITIES
Journal Editorial
§
Associate
editor Transportation Research Part A:
Policy and Practice (current)
§
Associate
editor Ingeniería de Transporte, Chilean Society of Transportation Engineers,
SOCHITRAN (2007-2010
and current). Co-editor (2011-2013)
§
Editorial
Board, Transportation Letters: The
International Journal of Transportation Research (current)
§ Editorial Board, Revista Geográfica del Sur (current)
Scientific Committees
§
Member,
Traveler Behavior and Values Committee, ADB10, Transportation Research Board,
National Academy of Sciences, USA (from 2011).
§
Co-chair,
Time Use and Activity Patterns Subcommittee, ADB10(3),
Transportation Research Board, National Academy of Sciences, USA (from 2014).
§
Member,
Telecommunications and Travel Behaviour Committee, ADB20, Transportation
Research Board, National Academy of Sciences, USA (from 2009).
§
Member,
Social and Economic Factors of Transportation Committee, ADD20, Transportation
Research Board, National Academy of Sciences, USA (from 2015).
§
Member,
International Steering Committee for Travel Survey Conferences (from 2010)
Scientific and Organizing Conference Committees
§
Member,
organizing committee, Uneven mobilities: Access to activities, people
and places in contemporary cities, organized by the PanAmerican
Mobility Network, Santiago de Chile, October 2014.
§
Chair,
scientific committee, Workshop on Urban
Sustainable Transportation, Santiago de Chile, September 2-4, 2013.
§
Member,
scientific committee 16th Congreso Chileno de Ingeniería de Transporte, Santiago
de Chile, October 21-24, 2013.
§
Member,
convening committee of the workshop series Frontiers in Transportation: Social
Interactions, Amsterdam
(2007), Toronto (2009, 2011), Munich (2013)
§
Member,
international network of researchers Time
Use Observatory (TUO)
§
Member,
international network of researchers ICT:
Mobilizing persons, places and spaces: An International Network on Information
and Communication Technologies, Everyday Life and Urban Change.
http://www.geo.uu.nl/mobilizingICT/index.php
Advisory Committees and Consultancy
§
Consultant
Project “Recommendations for the urban transport system in a model city: Talca”
(financed by the World Bank, 2011).
§
Member,
advisory committee tram project for Concepción (2009).
§
Member,
advisory committee of the Chilean National Transportation Policy White Paper.
Ministry of Transport of Chile (2013)
See also: Google
Scholar
Calastri, C., S. Hess, A. Daly, and J.A. Carrasco (2017),
“Does the social context help with understanding and predicting the choice of
activity type and duration? An application of the Multiple Discrete-Continuous
Nested Extreme Value model to activity diary data,” Transportation Research Part A,
forthcoming.
Chávez,
O.*, J.A. Carrasco, and A. Tudela (2017), “Social
activity-travel dynamics with core contacts: Evidence from a two-wave personal
network data,” Transportation Letters:
The International Journal of Transportation Research, forthcoming.
López,
F., A. Páez, J.A. Carrasco and N. Ruminot* (2017),
“Vulnerability of Nodes under Controlled Network Topology and Flow
Autocorrelation Conditions,” Journal of
Transport Geography, 59, 77-87.
Rojas, C.,
A. Páez, O. Barbosa, and J.A. Carrasco (2016), “Accessibility to Urban Green
Spaces in Chilean Cities using Adaptive Thresholds,” Journal of Transport Geography, 57, 227-240.
Lucas, K.,
J. Bates, J. Moore*, and J.A. Carrasco (2016), “Modelling the relationship
between travel behaviour and social disadvantage,” Transportation Research Part A, 85,
157-173.
Schwanen,
T., K. Lucas, N. Akyelken, D. Solsona*,
J.A. Carrasco, and T. Neutens, (2015), “Rethinking
the links between social exclusion and transport disadvantage through the lens
of social capital,” Transportation
Research Part A, 74, 123-135.
Farber, S.,
T. Neutens, J.A. Carrasco, and C. Rojas (2014),
“Exploration of Social Interaction Potential (SIP) and the spatial distribution
of face-to-face social interactions,” Environment and
Planning B, doi:10.1068/b120034p.
García, C., J.A. Carrasco, and C. Rojas (2014), “El contexto
urbano y las interacciones sociales: Dualidad del espacio de actividades de
sectores de ingresos altos y bajos, localizados en Concepción, Chile,” Eure¸ 40
(121), 75-99. [The urban
context and social interactions: Duality of the activity spaces of high and low
income groups, located in Concepción, Chile]. http://www.eure.cl/index.php/eure/article/view/478
Kowald, M.,
P. van den Berg, A. Frei, J.A. Carrasco, T. Arentze,
K. Axhausen, D. Mok, H.
Timmermans, and B. Wellman (2013), “Distance patterns of personal networks in
four countries: A comparative study,” Journal
of Transport Geography, http://dx.doi.org/10.1016/j.jtrangeo.2013.06.006. Preprint
Whalen, K.,
A. Páez, and J.A. Carrasco (2013), “Mode choice of university students
commuting to school and the role of active travel,” Journal of Transport Geography, 31, 132-142,
http://dx.doi.org/10.1016/j.jtrangeo.2013.06.008.
Moore, J.,
J.A. Carrasco, and A. Tudela (2013), “Exploring the
links between personal networks, time use, and the spatial distribution of
social contacts,” Transportation, 40(4), 773-788. Preprint
Carrasco,
J.A. and B. Cid-Aguayo (2012), "Network capital, social networks, and
travel: An empirical illustration from Concepción, Chile," Environment
and Planning A, 44(5), 1066-1084. Preprint
Carrasco,
J.A. (2011), "Personal network maintenance, face to face interaction, and
distance: Studying the role of ICT availability and use," Transportation Research Record: Journal of
the Transportation Research Board, 2231, 120-128. Preprint
Galdames,
C., A. Tudela, and J.A. Carrasco (2011),
"Exploring the role of psychological factors on mode choice models using a
latent variables approach" Transportation
Research Record: Journal of the Transportation Research Board, 2230, 68-74.
Preprint
Habib,
K.N., and J.A. Carrasco (2011), "Investigating the role of social networks
in start time and duration of activities: A trivariate
simultaneous econometric model," Transportation
Research Record: Journal of the Transportation Research Board, 2230, 1-8. Preprint
Mok, D.,
B. Wellman and J.A. Carrasco (2010), "Does distance matter in the age of
the Internet?" Urban Studies, 47(13), 2747-2784.Preprint
Carrasco,
J.A. and E. J. Miller (2009), "The social dimension in action: A
multilevel, personal networks model of social activity frequency," Transportation Research Part A, 43(1), 90-104. Preprint
M. Roorda, M., J.A. Carrasco, and E.J. Miller (2009), “A joint
model of vehicle transactions, activity scheduling, and mode choice”, Transportation
Research Part B, 43(2),
217-229. Abstract
Carrasco,
J.A., E.J. Miller, and B. Wellman, “"How far and with whom do people
socialize? Empirical evidence about distance between social network
members," Transportation Research Record: Journal of the
Transportation Research Board, 2076, 114-122. Preprint
Habib.
K.N., J.A. Carrasco, and E.J. Miller, "Social
context of activity scheduling: Discrete-continuous model of relationship
between "with whom" and episode start time and duration," Transportation Research Record: Journal of the Transportation Research
Board, 2076, 81-87. Preprint
Carrasco,
J.A., B. Hogan, B. Wellman, and E. J. Miller (2008), "Agency in social
activity and ICT interactions: The role of social networks in time and
space," Tijdschrift voor Economische en Sociale Geografie (Journal of
Economic & Social Geography), 99(5), 562-583. Preprint
Carrasco,
J.A., B. Hogan, B. Wellman, and E. J. Miller (2008), "Collecting social
network data to study social activity-travel behaviour: An egocentric
approach," Environment and Planning B, 35(6), 961-980. Abstract Preprint
Hogan, B.,
J. A. Carrasco, and B. Wellman (2007), “Visualizing personal networks: Working
with participant-aided sociograms”, Field Methods,
19(2) 116-144. Abstract Preprint
Carrasco,
J.A. and E. J. Miller (2006), "Exploring the propensity to perform social
activities: Social networks approach," Transportation, 33: 463-480.
Abstract Preprint
Miller,
E.J., M. Roorda, and J.A. Carrasco, (2005), “A
Tour-Based Model of Travel Mode Choice”, Transportation, 32: 399-422. Abstract
Carrasco J.A. and J. de D. Ortúzar (2002), “A Review and Assessment of the Nested
Logit Model”, Transport Reviews 22(2): 197-218. Abstract
Carrasco, J.A. and K.
Lucas (2015), “Measuring attitudes: quantitative and qualitative methods,” Transportation Research Procedia, 11,
165-171.
Carrasco, J.A.
(2015), “Personal characteristics, social contacts and transport systems,”
Chapter 6 in Social Networks and Travel Behaviour, M. Kowald and K. Axhausen (eds.), UK: Ashgate.
Frei, A., M. Kowald, P. van den Berg, and J.A. Carrasco (2015), “Country
specific characteristics matter,” Chapter 5 in Social Networks and Travel Behaviour, M. Kowald and K. Axhausen (eds.),
UK: Ashgate.
Carrasco, J.A.
(2014), “Transportation Policy of South America,” Encyclopedia of Transportation: Social Science and Policy, M.
Garret (eds.), USA: SAGE.
Morency, C. and J.A. Carrasco (2013),
“Photo stories of hard-to-model and hard-to-understand travel behavior,” in
Chapter 1 in Travel Behaviour
Research: Current Foundations, Future Prospect, M. Roorda
and E.J. Miller (eds.), USA: Lulu
Publishers.
Carrasco, J.A., C.
Bustos, and B. Cid-Aguayo (2013), “Affective personal networks versus daily
contacts: Analyzing different name generators in a social activity-travel behaviour context,” Chapter 22, p. 407-424, in Transport Survey Methods: Best Practice for
Decision Making, J. Zmud, M. Lee-Gosselin, M. Munizaga, and J.A. Carrasco (eds.), London: Emerald Press.
Daly, A. and J.A.
Carrasco (2009), "The influence of trip length on marginal time and money
values: An alternative explanation," Proceedings IATBR 2006, R. Kitamura
Ed. Elsevier.
Wellman, B., B.
Hogan, K. Berg, J. Boase, J. A. Carrasco, R. Côté, J. Kayahara, T. Kennedy,
and P. Tran (2006), "Connected Lives: The Project," Chapter 8 in The Networked Neighbourhoods, P. Purcell, Ed. Berlin: Springer. Preprint
Zmud, J., M. Lee-Gosselin, M. Munizaga, and J.A. Carrasco, eds. (2013), Transport Survey Methods: Best
Practice for Decision Making. London: Emerald Press.
Carrasco, J.A., S. Jara-Díaz, and M. Munizaga, eds.
(2011), Time Use Observatory. Ed.
LOM: Santiago de Chile.
Carrasco, J.A. and S.
Farber (2014), “Selected papers on the study of the social context of travel
behavior,” special issue for Transportation
Research Part A, 68, 1-2.
Dugundji, E., D. Scott, J.A. Carrasco, and
A. Páez (2012), “Urban mobility and social-spatial interaction,” special issue
of Environment and Planning A, 44(5),
1011-1015.
Dugundji, E., A. Páez, T. Arentze and J. Walker, with contributions from J.A.
Carrasco, F. Marchal, and H. Nakanishi (2011),
“Transportation and social interactions,” Guest Editorial, Transportation Research Part A, 45(4), 239-247.
Tudela, A., R. Daziano, and J.A. Carrasco (2013), “El papel de los factores contextuales, socioeconómicos y sicológicos en la elección de modo: Un estudio de caso de Concepción,” Ingeniería de Transporte, 17(1), 29-35.
De la Fuente, H., C. Rojas, M.J. Salado, J.A. Carrasco, and T. Neutens (2013), “Socio-spatial inequality in education facilities in the Concepción Metropolitan Area (Chile),” Current Urban Studies, 1(4), 117-129, DOI: 10.4236/cus.2013.14013. Webpage.
Roa, H., C. Rojas, J.A. Carrasco, and A. Tudela (2013), “Movilidad
urbana e indicadores de exclusión social del sistema de transporte: evidencia
en una ciudad intermedia chilena,” Revista
Transporte y Territorio, Universidad de Buenos Aires, Nº 8, 72-91. http://www.rtt.filo.uba.ar/numero08.html.
Versión pdf
Bustos, C. J.A. Carrasco, C. Rojas, and A. Tudela (2012), “Indicadores del espacio de actividades sociales de individuos del Gran Concepción utilizando la perspectiva de las redes personales,” Ingeniería de Transporte, 16.
Jara, M. and J.A. Carrasco (2010), "Indicadores de inclusión social, accesibilidad y movilidad: Experiencias desde la perspectiva del sistema de transporte", Ingeniería de Transporte, 14(1), 19-26.
Carrasco, J.A. (2007), "Redes sociales y comportamiento de transporte: Marco teórico y resultados empíricos", Ingeniería de Transporte, 13(1), 11-17.
Calastri, C., S. Hess, A. Daly, A. Pinjari and J.A. Carrasco (2017) “Dealing with discrete
continuous activity decisions across multiple days in the presence of day specific
constraints and preferences,” 5th
International Choice Modelling Conference, Cape Town, April, 3-5, 2017.
Calastri, C., S. Hess, J.A. Carrasco, C.
Choudhury and A. Daly (2017) “Keeping social contacts over time: The role of
life-course events and latent tie strength,” 5th International Choice Modelling Conference, Cape Town, April, 3-5,
2017.
Tudela, A., C. Durán,
J.A. Carrasco and A. Tapia (2017) “Does the design of the environment affect
the willingness to transfer between modes?” 5th
International Choice Modelling Conference, Cape Town, April, 3-5, 2017.
Calastri, C., S. Hess and J.A. Carrasco
(2017), "Incorporating the social dimension in the choice of activity type
and duration: an application of the Multiple Discrete-Continuous Extreme Value
(MDCEV) model" 96th Annual
Transportation Research Board Meeting, Washington, D.C., January 8-12,
2017.
Jirón, P., and J.A. Carrasco (2106),
“Interdependence, gender and mobility: Understanding mobility strategies in
Concepción, Chile,” 14th T2M Annual
Conference, The International Association for the History of Transport, Traffic
and Mobility, Mexico City, October 27-29, 2016.
Tudela, A., and J.A.
Carrasco (2106), “Obtención de matrices Origen Destino a partir de diagramas de
carga,” XIX Congreso Panamericano de
Ingeniería de Tránsito, Mexico City, September 28-30, 2016.
Calastri, C., S. Hess and J.A. Carrasco
(2016), “Investigating the impact of sociability and social networks on the
demand for leisure travel: implications for Chilean transport policy,” ITEA Annual Conference and School on
Transportation Economics, Santiago, June 14-17, 2016.
Tapia, A., A. Tudela, and J.A. Carrasco (2016), “Can personality factors
in mode choice affect the outcome of the transport investments decision making
process? A case study in the Chilean context,” 95th Annual Transportation Research Board Meeting, Washington,
D.C., January 10-14, 2016.
Sharmeen, F., O. Chávez, J.A. Carrasco, T. Arentze, and A. Tudela (2016),
“Modeling population-wide personal network dynamics using a two wave data
collection method and an origin-destination survey,” 95th Annual Transportation Research Board Meeting, Washington,
D.C., January 10-14, 2016.
Rojas, C., A. Páez,
O. Barbosa, and J.A. Carrasco (2016), “Measuring walking access to urban green
spaces: The role of age, gender, and income in two Chilean case studies,” 95th Annual Transportation Research Board
Meeting, Washington, D.C., January 10-14, 2016.
Chávez, O., J.A. Carrasco,
and A. Tudela (2015), “Un estudio de las dinámicas de redes sociales personales
para el estudio de actividades y viajes sociales utilizando fusión de datos en
dos cortes temporales,” XVII Congreso
Chileno de Ingeniería de Transporte, Concepción, 13-16 October,
2015.
Urrutia, N., A. Tudela, and
J.A. Carrasco (2015), “Cobertura espacial, temporal y económica del transporte
público en el Gran Concepción: Un estudio basado en indicadores,” XVII Congreso Chileno de Ingeniería de
Transporte, Concepción, 13-16 October, 2015.
Tapia, A., A. Tudela, and
J.A. Carrasco (2015), “Impacto de los factores contextuales, socioeconómicos y
psicológicos sobre la cuantificación de beneficios de un proyecto de
transporte,” XVII Congreso Chileno de
Ingeniería de Transporte, Concepción, 13-16 October
2015.
Rojas, C., J.A. Carrasco, F. Pérez, G. Araneda, and C. García (2015), “Análisis espacial de redes sociales,” XV Conferencia Iberoamericana de Sistemas de Información Geográfica, Valparaíso, 10-11 de septiembre de 2015.
Bustamante, R., A.
Tapia, A. Tudela, and J.A. Carrasco, J.A. (2015)
“Does transport have any role on well-being? A Chilean case study” 14th International Conference on Travel Behaviour Research, Windsor, 19-23 July 2015.
Van den Berg, P., and
J.A. Carrasco (2015) “Intrapersonal changes in social activity-travel patterns:
Linking time use and social network dynamics,” 14th International Conference on Travel Behaviour
Research, Windsor, 19-23 July 2015.
Bustamante, R., A.
Tapia, A. Tudela, and J.A. Carrasco, J.A. (2015),
“Assessing transport disadvantage and transit use through people’s knowledge,
experience, and barriers to activities
and modes,” 14th International Conference
on Competition and Ownership in Land Passenger Transport (Thredbo
14), Santiago de Chile, 30 August - 3 September 2015.
Chávez, O., J.A.
Carrasco, and A. Tudela (2015) “Social
activity-travel dynamics with core contacts: Evidence from a two-wave personal
network data” 94th Annual Transportation
Research Board Meeting, Washington, D.C., January 11-15, 2015.
Carrasco, J.A, D. Sandoval, O.
Chávez, and B. Cid-Aguayo (2014) “Spatial and temporal dynamics on personal
networks: Some methodological and theoretical challenges to study their
embedded social travel behavior” 10th
International Conference on Transport Survey Methods¸ Leura,
Australia, November 16-21, 2014.
Bustamante, R., S. Baeza, A. Tudela, and J.A.
Carrasco (2014) “Measuring social exclusion using a non-normative approach” 10th International Conference on Transport
Survey Methods¸ Leura, Australia, November 16-21,
2014.
Carrasco, J.A., A. Tudela, C. Rojas (2014), “A mobility perspective on urban
segregation and social exclusión: Evidence from
personal networks from four Chilean neighbourhoods,” Uneven mobilities. Access to activities,
people and places in contemporary cities, PanAmerican
Mobilities Network, Santiago de Chile, October 13-16, 2014.
Tapia, A., A. Tudela, and J.A. Carrasco (2014), “El impacto de variables psicológicas en la estimación y predicción de la demanda. Un estudio de caso en Concepción,” XVIII Congreso Panamericano de Ingeniería de Tránsito, Transporte y Logística, Santander, España, June 11-13, 2014.
Linco, H., J.A. Carrasco, and A. Tudela (2014), “Actividades y viajes sociales en Concepción, Chile: Un estudio comparativo de las características temporales, espaciales y sociales de las redes personales de viajeros de cuatro barrios,” XVIII Congreso Panamericano de Ingeniería de Tránsito, Transporte y Logística, Santander, España, June 11-13, 2014.
Cerda, Z., A. Tudela, J.A. Carrasco, and S. Baeza (2014) “Exclusión social: El conocimiento y experiencia acerca de actividades y las barreras para el desarrollo de éstas,” XVIII Congreso Panamericano de Ingeniería de Tránsito, Transporte y Logística¸ Santander, España, June 11-13, 2014.
Rojas, C., A. Schäfer,
F. Aguilera, C. Peyrin, J.A. Carrasco, A. Tudela, T. Neutens (2014),
“Accessibility to educational and health facilities in the middle city of Los
Angeles, Chile, as an indicator of transport disadvantage,” NECTAR Cluster 6 meeting: Accessibility and
Policy Making, Sevilla, February 6-7, 2014.
Tapia, A., V. Sichel, A. Tudela, and J.A. Carrasco (2013), “El impacto de variables de personalidad en la estimación de la demanda: Un estudio de caso en Concepción,” in XVI Congreso Chileno de Ingeniería de Transporte, Santiago de Chile, October 22-25, 2013.
Moore, J., J.A. Carrasco, and A. Tudela (2013), “Exploring the links between personal
networks, time use, and the spatial distribution of social contacts,” in 92nd Annual Meeting of the Transportation Research Board,
Washington D.C., January 13-17, 2013.
Farber, S., T. Neutens,
J.A. Carrasco, and C. Rojas (2013), “Exploration of Social Interaction
Potential (SIP) and the Spatial Distribution of Face-to-face Social
Interactions,” in 92nd Annual Meeting of the Transportation
Research Board, Washington D.C., January 13-17, 2013. Also presented at the
13th International Conference on Travel Behaviour
Research, Toronto, 15-20 July 2012.
Lucas, K., J. Bates, J. Moore, and
J.A. Carrasco (2013) “Modeling the relationship between tranvel
behaviours and social disadvantage,” 45th Annual Universities’ Transport Studies
Group (UTSG) Conference, Oxford, UK, January 2-4, 2013.
Schwanen, T., K. Lucas, J.A. Carrasco, T. Neutens, N. Akyelken D. Solsona (2013) “Reconceptualising
the links between transport disadvantage and social exclusion,” 45th Annual Universities’ Transport Studies
Group (UTSG) Conference, Oxford, UK, January 2-4, 2013.
Martínez, M., C. Rojas, J.A. Carrasco, and A. Codeço (2012), “Indicadores de accesibilidad para la evaluación territorial de la red por carretera desde una perspectiva geográfica,” PANAM 2012: XVII Congreso Panamericano de Ingeniería de Tránsito y Transporte y Logística, Santiago de Chile, September 24-27, 2012.
Roa, H., M. Jara, J.A. Carrasco, C. Rojas, and A. Tudela (2012), “Contexto urbano e indicadores de exclusión social relacionada al sistema de transporte: Evidencia de dos ciudades chilenas,” PANAM 2012: XVII Congreso Panamericano de Ingeniería de Tránsito y Transporte y Logística, Santiago de Chile, September 24-27, 2012.
Tudela, A., R. Daziano, and J.A. Carrasco (2012), “El papel de los factores contextuales, socioeconómicos y psicológicos en la elección de modo: Un estudio de caso en Concepción,” PANAM 2012: XVII Congreso Panamericano de Ingeniería de Tránsito y Transporte y Logística, Santiago de Chile, September 24-27, 2012.
Cerda, Z., A. Tudela,
J.A. Carrasco (2012), “On the role of personality when assessing the role of
transport on social exclusion,” Fifth
International Conference on Traffic and Transport Psychology, Groningen,
The Netherlands, August 29-31, 2012.
Kowald, M., P. van den Berg, A. Frei, J.A.
Carrasco, T. Arentze, K. Axhausen,
D. Mok, H. Timmermans, and B. Wellman (2012),
“The Spatiality of Personal Networks in Four Countries: A Comparative Study,” 13th International Conference on Travel Behaviour Research, Toronto, 15-20 July 2012.
Tudela, A., J.A. Carrasco, and R. Daziano (2012), “Personal factors on mode
choice: Attitude, affect, social and habit. Measuring and studying their role,”
13th International Conference on Travel Behaviour Research, Toronto, 15-20 July 2012.
Jara, M., J.A. Carrasco, A. Tudela, and C. Rojas (2001), “Indicadores del rol del sistema de transportes en la exclusión social: Metodología y aplicación en el Gran Concepción,” XXXII Congreso Nacional y XVII Internacional de Geografía, Valparaíso, Chile, November 22-25, 2011.
Carrasco. J.A., C. Bustos, and B.
Cid-Aguayo (2011), “Affective personal networks versus daily contacts:
Analyzing different name generators in an activity-travel behaviour context,”
in 9th International Survey Methods
Conference, Termas de Puyehue,
Chile, November 14-18, 2011.
Bustos, C. J.A. Carrasco, and C. Rojas (2011), “Indicadores del espacio de actividades sociales de individuos del Gran Concepción utilizando la perspectiva de las redes personales,” in XV Congreso Chileno de Ingeniería de Transporte, Santiago de Chile, October 3-6, 2011.
Carrasco J.A. (2011), “Redes sociales, movilidad espacial y patrones de interaccion: Cuatro barrios de Concepcion, Chile,” in XXVIII Congreso Internacional de la Asociación Latinoamericana de Sociología (ALAS), Recife, September 6-11, 2011.
Tudela, A., K.N. Habib, A. Osman, and J.A.
Carrasco (2011), “Incorporating the explicit role of psychological factors on
mode choice: A hybrid mode choice model by using data from an innovative
psychometric survey,” in International
Choice Modelling Conference 2011, Leeds, U.K., July 4-6, 2011.
Carrasco, J.A. (2011),
"Personal network maintenance, face to face interaction, and distance:
Studying the role of ICT availability and use," in 90th Annual Meeting
of the Transportation Research Board, Washington D.C., January 23-27, 2011.
Habib, K.N., and J.A. Carrasco
(2011), "Investigating the role of social networks in start time and
duration of activities: A trivariate simultaneous econometric model, " in 90th
Annual Meeting of the Transportation Research Board, Washington D.C.,
January 23-27, 2011. A previous version was presented at 12th World
Conference on Transport Research, Lisbon, Portugal, July
11-15, 2010.
Galdames, C., A. Tudela,
and J.A. Carrasco (2011), "Exploring the role of psychological factors on
mode choice models using a latent variables approach" in 90th Annual
Meeting of the Transportation Research Board, Washington D.C., January
23-27, 2011.
Céspedes, N., A. Páez and J.A. Carrasco
(2010), “Tertiary streets and the strength of autocorrelation using Moran`s
Coefficient,” 57th Annual North American Meetings of the Regional
Science Association International, Denver, November 11-13, 2010.
Jara, M. and J.A. Carrasco (2010), “Indicadores
temporales y espaciales de exclusión social y transporte: Una ilustración
empírica,” PANAM 2010: XVI Congreso Panamericano de Ingeniería de Tránsito y
Transporte y Logística, Lisbon, Portugal, July 15-18, 2010.
Ruminot, N., A. Páez, and J.A. Carrasco
(2010), "Network Topology, Autocorrelation, and Node Vulnerability,"
in 89th Annual Meeting of the Transportation Research Board, Washington
D.C., January 10-14, 2010.
Carrasco, J.A (2009),
"Unravelling the social, urban, and time-space context of activity-travel
behaviour: Results from a social network data collection experience", 12th
International Conference on Travel Behaviour Research, Jaipur, December
13-18, 2009.
Carrasco, J.A and K.N. Habib (2009),
"Understanding the social embeddedness of activity-travel participation:
The case of frequency and duration of social activities", 12th
International Conference on Travel Behaviour Research, Jaipur, December
13-18, 2009.
Jara, M. and J.A. Carrasco (2009), “Indicadores de
inclusión, accesibilidad y movilidad espacial: Análisis desde la perspectiva
del comportamiento de transporte urbano,” XV Congreso Latinoamericano de
Transporte Público y Urbano – CLATPU, Buenos Aires, Argentina, March 31 – April 3, 2009.
Carrasco, J.A., J. Núñez, and K. Inostroza (2008), “Redes sociales y movilidad diaria en el
espacio urbano: Marco teórico, datos y métodos de análisis,” XXIX Congreso
Nacional y XIV Internacional de Geografía, Temuco, Chile, October 14-17, 2008.
Ruminot, N., A. Páez, and J.A. Carrasco
(2008) “Vulnerable nodes in networks: An autocorrelation approach,” 48th Congress of the European Regional
Science Association, Liverpool, August 27-31, 2008.
Mok, D.,
B. Wellman and J.A. Carrasco (2008), “Does distance matter in the age of the
Internet: Are cities losing their comparative advantage?,”
103rd Annual Meeting of the American Sociological Association,
Boston, August 1-4, 2008. Preprint
Carrasco,
J.A., E.J. Miller, and B. Wellman, (2008), "How far and with whom do people socialize? Empirical evidence about
distance between social network members," in 87th Annual Meeting of the Transportation
Research Board,
Washington D.C., January 13-17, 2008. A previous version of this paper was presented at the 53rd
Annual North American Meetings of the Regional Science Association
International, Toronto,
November 26-28, 2006.
Habib.
K.N., J.A. Carrasco, and E.J. Miller (2008), "Social context of activity scheduling: Discrete-continuous model of
relationship between "with whom" and episode start time and duration," in 87th Annual Meeting of the Transportation Research Board,
Washington D.C., January 13-17, 2008. A previous version of this paper was presented at the XIII Congreso Chileno
de Ingeniería de Transporte, Chile, Santiago, October 22-26,
2007.
Carrasco, J.A.
(2007), "Redes sociales y comportamiento de transporte: Marco teórico y
resultados empíricos", in XIII
Congreso Chileno de Ingeniería de Transporte, Chile, Santiago, October 22-26, 2007. (Full
text available upon request)
Carrasco,
J.A., D. Mok, and B. Wellman (2007), "Integrating distance, travel, and the mode of
contact: The Connected Lives Study", Communities and Technologies 2007, Michigan, June 28-30,
2007. (Full text available upon request)
Habib,
K.M.N, J.A. Carrasco, and E.J. Miller (2007), "The social dimension of individual’s activity scheduling: How “with
whom” influences activity participation", 11th
World Conference on Transport Research, Berkeley, June 24-28, 2007.
Hogan, B.,
J.A. Carrasco, and B. Wellman (2007), "
Maintaining ties near and far: Agency and social accessibility in personal
communities", 102nd
Annual Meeting of the American Sociological Association, New York, August
11-14, 2007. A previous
version of this paper was presented at the International Sunbelt Social Network
Conference XXVII, Corfu Island, Greece, May
1-6, 2007. (Full text available upon request)
Carrasco,
J.A. and E. J. Miller (2007), "The social dimension in action: A
multilevel, personal networks model of social activity frequency," in 86th
Annual Meeting of the Transportation Research Board, Washington D.C.,
January 21-25, 2007. Preprint
Carrasco,
J.A., E.J. Miller, and B. Wellman, (2006), “Spatial and social networks: The
case of travel for social activities”, 11th International Conference on Travel
Behaviour Research, Kyoto, August 16-20, 2006. Abstract (Full text available upon request)
M. Roorda, M., J.A. Carrasco, and E.J. Miller (2006), “A joint
model of vehicle transactions, activity scheduling, and mode choice”, 11th International Conference on Travel
Behaviour Research, Kyoto, August 16-20, 2006. Abstract
Daly, A.
and J.A. Carrasco (2006), “The influence of trip length on marginal time and
money values”, 11th International Conference on Travel
Behaviour Research, Kyoto, August 16-20, 2006. Abstract
Carrasco, J.A., B. Hogan, B. Wellman, and E. J. Miller (2006),
"Collecting social network data to study social activity-travel behavior:
An egocentered approach," in 85th Annual Meeting of the
Transportation Research Board, January 22-26, 2006, Washington D.C. [Also
presented at MCRI/GEOIDE Second International Colloquium on the Behavioural
Foundations of Integrated Land-use and Transportation Models: Frameworks,
Models and Applications, Toronto, June 13-14, 2005; and as an invited paper at
the workshop Frontiers in Transportation: Social and Spatial Interactions,
Amsterdam, Netherlands, July 2-6, 2005]
Carrasco,
J.A. and E. J. Miller (2006), "Exploring the propensity to perform social
activities: A social networks approach," in 85th Annual Meeting of the Transportation
Research Board, January 22-26, 2006, Washington D.C.
Carrasco,
J.A. and E. J. Miller (2005), "Socialising with people and not places:
Modelling social activities explicitly incorporating social networks," in 9th Computers in Urban Planning and
Urban Management Conference, London, June 29 - July 1, 2005. (Full
text available upon request)
Miller,
E.J., M. Roorda, and J.A. Carrasco, (2003), “A
Tour-Based Model of Travel Mode Choice”, 10th International Conference on
Travel Behaviour Research, Lucerne, 10-15 August,
2003. Abstract
Carrasco J.A., J de D. Ortúzar, and M. Munizaga (2001), “Una revisión y análisis del modelo Logit Jerárquico”, 8th Chilean Transport Engineering Conference, 8 -12 October 2001, Concepción (in Spanish). Abstract
Universidad de Concepción
Modelos de Demanda de Transporte
Redes de Transporte
Fundamentos de la Ingeniería de Transporte
Planificación de Transporte
Uso de Suelo y Transporte
Métodos de Optimización
Desafíos de la Ingeniería Civil
Seminario de Tesis de Magíster
University of Toronto
Probability and Statistics for Civil Engineers
ABSTRACTS
A Review and Assessment of the
Nested Logit Model
J.A. Carrasco and J. de D. Ortúzar
Abstract
The popular hierarchical or nested
logit model that has been the recent source of heated discussions in the
literature is reviewed and critically examined. The fundamental underpinnings
of the model are first presented in a concise and easy-to-understand fashion
and then used to assess each controversy in turn. Monte Carlo simulation is
also used to examine some problems that are not possible to address by just
resorting to the theory. The main conclusion is that all the model hypotheses
are both essential and unambiguous and should not be ignored for a correct use
of the model in practice.
A Tour-Based Model
of Travel Mode Choice
E.J. Miller, M. Roorda,
and J.A. Carrasco
Abstract
This paper presents a new tour-based
mode choice model. The model is agent-based: both households and
individuals are modelled within an object-oriented, microsimulation
framework. The model is household-based in that inter-personal household
constraints on vehicle usage are modelled, and the auto passenger mode is
modelled as a joint decision between the driver and the passenger(s) to
ride-share. Decisions are modelled using a random utility
framework. Utility signals are used to communicate preferences among the
agents and to make trade-offs among competing demands. Each person is
assumed to choose the “best” combination of modes available to execute each
tour, subject to auto availability constraints that are determined at the
household level. The household’s allocations of resources (i.e., cars to
drivers and drivers to ride-sharing passengers) are based on maximizing overall
household utility, subject to current household resource levels. The model
is activity-based: it is designed to be integrated within a household-based
activity scheduling microsimulator. The model
is both chain-based and trip-based. It is trip-based in that the ultimate
output of the model is a chosen, feasible travel mode for each trip in the
simulation. These trip modes are, however, determined through a chain-based
analysis. A key organizing principle in the model is that if a car is to
be used on a tour, then it must be used for the entire chain, since the car
must be returned home at the end of the tour. No such constraint, however,
exists with respect to other modes such as walk and transit. The paper presents
the full conceptual model and an initial empirical prototype.
A Review and
Assessment of the Nested Logit Model
J.A. Carrasco and
J. de D. Ortúzar
Abstract
The popular
hierarchical or nested logit model that has been the recent source of heated
discussions in the literature is reviewed and critically examined. The
fundamental underpinnings of the model are first presented in a concise and
easy-to-understand fashion and then used to assess each controversy in turn. Monte
Carlo simulation is also used to examine some problems that are not possible to
address by just resorting to the theory. The main conclusion is that all the
model hypotheses are both essential and unambiguous and should not be ignored
for a correct use of the model in practice.
Exploring the propensity to
perform social activities: A social networks approach
J.A. Carrasco, and E.
J. Miller
Abstract
A
conceptual model of social activity-travel behaviour is described,
incorporating an activity-scheduling framework which explicitly includes the
influence of the individual’s social context. More explicitly, the model
develops the concepts of social networks, activities, and social episodes, and
defines the individual’s social activity generation and spatial distribution in
a context of his/her social networks. Also, empirical findings regarding the
influence of social network characteristics on individual’s socialising
patterns are discussed. Results suggest that a social networks framework
provides interesting insights into the role of physical space, and
communication and information technology use. Overall, explicitly incorporating
social networks into the activity-travel behaviour modelling framework provides
a rich set of insights to understand social activities and the embedded
behavioural processes, potentially helping to better understand important
issues such as the generation and spatial distribution of activities and
travel.
Collecting social network data
to study activity-travel behaviour: An egocentred approach
J.A. Carrasco, B. Hogan, B. Wellman, and E. J.
Miller
Abstract
Within the
study of activity and travel demand, there has been an increasing interest in
the effect of social interactions in activity-travel behaviour, that is, how
social networks influence activity-travel decisions. Despite this interest, to
the authors’ knowledge, no data collection effort has linked explicitly travel
behaviour and social interaction, so far. Moreover, although data collection
and modelling techniques have gone very far understanding individual
activity-travel decision making processes in time and space, we know very
little about the linkages between social and spatial interactions. In a
companion paper, we showed a conceptual model of social activity-travel
behaviour, that links three elements: the characteristics of individuals, their
social networks, and the social activity-travel behaviour that arises in this
context.
This paper
presents the data collection effort designed to partly support that model,
including the main research questions and characteristics of the data, the
conceptual options taken, the main techniques used, the practical issues and
limitations of the method selected, and the expected results.
The data
was gathered in the East York area of Toronto between June 2004 and March 2005,
as part of the “Connected Lives Study”, a broader study composed by surveys,
interviews, and observations about people’s communication patters. The study
was conducted by the first author in conjunction with sociologists and social
workers of the NetLab, part of the Centre of Urban
and Community Studies at the University of Toronto, and lead by the sociologist
Barry Wellman. The multidisciplinary setting allowed for a rich
crossed-fertilisation in data collection techniques, and a broad set of
information gathered.
Having as a
motivation the study of social and spatial interactions, this paper discusses
the way social network data was collected, and the link made with
activity-travel behaviour pattern data. Social network data is traditionally
gathered in two ways: as whole and ego-centered networks. Whole
network studies consist in asking interviewee about her relationships with
closed (pre-defined) list of individuals; however, in an urban setting like the
one studied this was unpractical. Then, an ego-centered approach was
taken, which consists in asking each interviewee (ego) an open-list of
individuals related with her (alters). The way the alter names
are elicited heavily determines how many and who are the individuals in the
individual’s network; in this case, instead of specific prompting questions, we
preferred using a loosely definition of people “very close” and “somewhat
close” to the interviewee. Both the ego-centered and the
alter eliciting technique have conceptual consequences; the most
important is conceiving the personal network as a Ptolemaic universe, with the
ego in the centre and the alters around. That is, the data, although collecting
interaction among individuals, is still individual-based. Another consequence
of open lists is that the relationships between the alter
and the ego, and among the alters is left to the interviewee’s criterion.
The paper
then focuses in the way social activity-travel behaviour was linked after the
social network was built. The interviewee was asked about frequencies of
face-to-face and socialising meetings (the last one conceived as visiting,
hosting or going to restaurants and pubs) with a sample of alters, and also the
frequency of telephone and email interaction, some alter’s
characteristics (including the main places they interact with the ego). In
addition, we gathered explicit information about time and space characteristics
of the last six social events with some of the alters.
The main hypothesis behind this way of collecting social travel behaviour data
is that the main individual’s social activities arise from the social
network, that is, instead of directly start asking about their activities and
travel, the main focus is on with whom the individual usually performs
social activities. We believe in this way we are able to get a good sense of
the individual’s socialising patters, although sacrificing some level of
detail.
Finally, we
discuss some limitations and the way they were minimised. A first limitation of
ego-centered techniques is the risk of prompting a small network. We limited
this drawback doing this exercise in the interview stage rather than in the
survey, and using an analog instead of a computer approach. Regarding the
decision of performing interviews, we believe this helped to gather more data
than what we could have gathered in a survey format; controlling for the
quality of the network building process; and finally getting a rich set of
qualitative data, including comments, extra information, and the interviewee
behavioural context. The analog approach we adopted consisted in using paper
and pencil rather than a computer interface. This option diminished the burden in
the interviewees and – we believe – also increased their motivation, especially
because they built in step-by-step procedure their network in a paper, rather
than adding names in a computer interface, which usually is a black box for the
interviewees.
A second
important limitation is the set of sampling procedures from the network. In
fact, large networks were usually prompted and a sampling strategy was needed.
We developed a sampling strategy based in a combination of the
alter’s social
closeness attributes and the frequency of interaction. This strategy balanced,
on the one hand, capturing a relevant subset of the interviewee’s network (i.e.
a relevant sample in their social space), and on the other hand, capturing a
relevant set of her activity-travel events (i.e. a relevant sample in their
activities and physical space).
The paper
also discusses the main qualitative and quantitative information obtained, and
how both qualitative and quantitative approaches are complementary and useful
to build and inform the conceptual model that motivated this data
collection effort. Finally some potential future extensions and methods related
with this data collection are discussed.
Visualizing personal networks: Working with participant-aided sociograms
B. Hogan,
J.A. Carrasco, and B. Wellman
Abstract
We describe an interview-based data collection
procedure for social network analysis designed to (a) aid gathering information
about the people known by a respondent and reduce problems with (b) data integrity,
and (c) respondent burden. This procedure, a participant-aided network diagram
(sociogram), is an extension of traditional name
generators. While such a diagram can be produced through computer assisted
programs for interviewing (CAPIs) and low-technology (i.e., paper), we
demonstrate both practical and methodological reasons for keeping high
technology in the lab and low technology in the field. We provide some general
heuristics that can reduce the time needed to complete a name generator. We present
findings from our Connected Lives field study to illustrate this procedure.
Una revisión y análisis
del modelo Logit Jerárquico
J.A. Carrasco, J de D. Ortúzar, and M. Munizaga
Abstract
Sorprende que, tras 25 años de haber sido formulado, aún no se comprendan
cabalmente algunas propiedades del modelo logit jerárquico y se discuta su
especificación. De hecho, este popular modelo ha sido objeto de una serie de
acaloradas discusiones recientemente en la literatura. El objetivo de este
trabajo es revisar las principales características del modelo en profundidad y
examinarlas críticamente, a fin de aclarar todas las controversias. En primer
lugar, se presentan los fundamentos teóricos del modelo, de forma concisa y
fácil de entender, para luego examinar cuatro controversias en torno a su
especificación: la correcta resolución del problema de no identificabilidad
(común a todos los modelos de elección discreta), la aplicabilidad de la
popular forma funcional NNNL, utilizada en el paquete estadístico ALOGIT, las
reproducción de las particiones de mercado observadas y la pertinencia de una
nueva especificación alternativa que provoca confusiones en relación a ciertas
propiedades del modelo. Aparte del análisis teórico, se utiliza también
simulación de Montecarlo para dilucidar algunos de estos aspectos. En este
contexto, la principal conclusión del trabajo es que todas las hipótesis del
modelo son esenciales para su correcta especificación e interpretación, y no
deben ser ignoradas para un adecuado uso del modelo en la práctica
The Influence of
Trip Length on Marginal Time and Money Values
Andrew Daly and J. A. Carrasco
Abstract
The work described in this paper is motivated
by the strong empirical finding that the marginal trade-off between time and
money in travellers’ decision-making appears to vary with the length of the
trip. Specifically, travellers over longer distances appear to have a higher
‘value of time’ (VOT) and this effect appears to be caused by a declining
marginal disutility of expenditure, rather than an increasing marginal
disutility of spending time. There is no a priori reason to expect that VOT
should increase in this way, indeed there seems to be good theoretical reason
to expect an opposite trend, so that interest in this issue is natural. In
particular, the consequences for project appraisal can be significant: is it
correct to attribute a higher value to time savings for travellers making
longer journeys than those making shorter journeys?
In practice, analysts have dealt with the effect in different ways for
forecasting and appraisal, although the approaches that have been adopted can
be justified only on the basis that they are approximations to an unknown
‘true’ underlying model. For example, the use of a ‘log cost’ formulation can
improve the fit of models to data but is not reasonable with respect to
individuals’ money budgets – the marginal disutility of expenditure must
increase as the amount of expenditure increases.
To deal properly with these questions requires that an explanation is given for
the observed effect. A number of hypotheses have been suggested to explain the
effect and these are reviewed in the paper and their consequences assessed.
Several of these hypotheses suggest that the primary mechanism by which VOT
increases is through heterogeneity between individuals in taste relative to
expenditure. Thus if individuals differ in their sensitivity to price, there
will be a self-selection so that those making more expensive journeys will tend
to be those with lower sensitivity to price. The effect can be reduced by
segmenting the population, for example with respect to income, but an important
degree of heterogeneity can remain.
The analysis is set in the Random Utility modelling framework because of the requirement
for consistency with economic theory for project appraisal, because this was
the basis used for the initial modelling with the data sets concerned and
because this framework gives a good basis for modelling.
The work then set out to test the hypothesis of heterogeneity with respect to
cost on data sets collected in different ways in different countries: Revealed
Preference data from Sydney (1991/2 and 1997/8) and from Paris (1991/2) and
Stated Preference data from The Netherlands (1988 and 1997). Existing models
which incorporated distance-dependent cost sensitivity terms were reformulated
and extended to incorporate heterogeneity of the type described, using a ‘mixed
logit’ formulation to handle the heterogeneity. A number of problems had to be solved
to reduce the volume of calculation. The analysis was restricted to commuters
to keep its scope reasonable.
The results show variation between the data sets but that significant
heterogeneity exists in all the data sets analysed. This heterogeneity exists
for both time and cost, but more importantly for cost than for time. It appears
that, on the whole, the assumption of heterogeneity with a linear cost
disutility gives a better explanation of the effects observed – in terms of the
fit of the model to the data – than the alternative hypothesis that marginal
sensitivity to cost declines with increasing cost. An important further finding
is that average VOT and elasticity with respect to time and cost variables can
change significantly between different model formulations, and generally are
more reasonable when the cost formulation is linear, so that it is quite
important to find the right specifications for these models and advantageous to
use the formulations with heterogeneity.
The results thus support the hypothesis of self-selection, but also hypotheses
that higher prices are not well perceived or are valued proportionately could
also be advanced on the basis of the empirical findings. The consequences for
of the findings for appraisal would depend on which of these hypotheses were
found most plausible. For forecasting, the consequences will remain limited,
because it is not yet possible to use mixed logit formulations in large-scale
forecasting.
A Joint Model of Vehicle
Transactions, Activity Scheduling and Mode Choice
M. Roorda, J. A. Carrasco, and E. J. Miller
Abstract
A joint model of vehicle transactions, activity
scheduling and mode choice is estimated based on a retrospective survey of
vehicle transactions in the Greater Toronto Area. The vehicle transaction model
includes, as explanatory variables, measures of activity/travel stress that are
simulated using the Travel Activity Scheduler for Household Agents (TASHA).
TASHA is a sophisticated activity-based microsimulation model of activity
scheduling and mode choice that represents household interactions of vehicle
allocation, ridesharing to joint activities, and drop-off/pick-up of household
members. The empirical analysis and model results indicate that there exists an
asymmetry in vehicle transactions. Households increase their activity/travel
stress far more by disposing of a vehicle, than they alleviate stress by
purchasing of a vehicle. Two measures of stress are found to be moderately
significant influences on vehicle transactions: the mode choice utility gained
by purchasing a vehicle, and the number of conflicts experienced in the
household over a limited number of vehicles. This model makes a behavioural
contribution by addressing the lack of sophistication typically found in the
vehicle usage component of vehicle ownership / transaction models. The model
also breaks new ground in the linking of long and short run decisions within a
clear conceptual and modelling framework.
Spatial and Social Networks: The Case of Travel for Social Activities
J. A.
Carrasco, E. J. Miller, and Barry Wellman
Abstract
Hägerstrand’s argument that Regional Science is about people and not only locations
is still a compelling and challenging idea when studying the spatial
distribution of activities. In the context of social activity-travel behaviour,
this issue is particularly important since the main individuals’ driver to
perform a trip is mostly with whom they interact rather than where they go.
Using a personal networks approach to measure and study social activity-spaces,
which focuses in the relationships of specific individuals (egos) with others
(alters), this paper conceptualises social and physical space as a phenomenon
beyond the traditional individualistic perspective, showing the need of
studying interactions between individuals in a more explicit way. The paper
presents the relationships between social activity spaces and the
characteristics of egos and their personal networks. Overall, the results strongly
suggests that, although –by definition – the spatial distribution of social
interaction is an idiosyncratic phenomenon, there are several systematic
effects, related with the characteristics of egos and their personal networks,
which affect this spatial distribution, and which can serve to better
understand where people perform social interactions with others.