John L. Bowman, Ph. D.
Transportation Systems and Decision Sciences

Bowman Research and Consulting

28 Beals Street
Brookline, MA  02446
USA

Telephone:  617-232-8189
 John_L_Bowman@alum.mit.edu


Resume

Short version
Long version

Biography

Project summaries and references

Papers

Theses

Refereed publications

Other publications and working papers

Presentations

Project documents

Sacramento:  SACSIM Activity-Based Travel Forecasting Model for SACOG, Featuring DAYSIM—the Person Day Activity and Travel Simulator

Seattle:  Activity-Based Model Development for Puget Sound Regional Council (PSRC)

Planning studies for advanced model development

Software

Last updated on February 23, 2010
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Theses

Bowman, John L. (1998) The day activity schedule approach to travel demand analysis, Ph.D. Dissertation, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.  185 pages.

Further develops the activity schedule model (see 1995 Thesis), emphasizing (a) the influence of activity accessibility on activity participation, at-home vs on-tour decisions, trip chaining and inter-tour trade-offs, and (b) the influence of lifestyle on activity and activity pattern utility.  Includes an empirical implementation of the model system for Portland, Oregon.

Synopsis (PDF)       Thesis (658K PDF)


Bowman, John. L. (1995) Activity based travel demand model system with daily activity schedules, Master of Science Thesis in Transportation, Massachusetts Institute of Technology, 92 pages.

Presents an integrated activity based discrete choice model system of an individual's daily activity and travel schedule, intended for use in forecasting urban passenger travel demand.  The system is demonstrated using data from the Boston metropolitan area.

Thesis (220K PDF)


Refereed publications

Bradley, Mark, John L. Bowman and Bruce Griesenbeck (2010) SACSIM: An applied activity-based model system with fine-level spatial and temporal resolution, Journal of Choice Modeling (publication pending)

Presents the regional travel forecasting model system (SACSIM) being used by the Sacramento (California) Area  Council of Governments (SACOG).  The paper explains the model system structure and components, the integration with the traffic assignment model, calibration and validation, sensitivity tests, model application and Federal peer review results.

Pre-publication draft of paper (249K PDF)


Dong, Xiaojing, Moshe E. Ben-Akiva, John L. Bowman and Joan Walker (2006) Moving from Trip-Based to Activity-Based Measures of Accessibility, Transportation Research Part A, 40(2006), pages 163-180.

Studies the properties and performance of an accessibility measure derived from the Day Activity Schedule (DAS) model system, comparing it with traditional trip-based measures, including isochrones, gravity-based measures and simpler utility-based measures.

Pre-publication draft of paper (143K PDF)


Bowman, J. L. and M. E. Ben-Akiva (2001) Activity-based disaggregate travel demand model system with activity schedules, Transportation Research Part A, 35(2001), pages 1-28.

A refined and shortened version of Bowman's Master's thesis (see above).

Pre-publication draft of paper (119K PDF)


Bowman, John L., Mark A. Bradley, Yoram Shiftan, T. Keith Lawton and Moshe E. Ben-Akiva (1998) Demonstration of an activity based model system for Portland, 8th World Conference on Transport Research, July 12-17, 1998, Antwerp, Belgium.

Reports the first operational implementation, in Portland, Oregon, of the activity-based travel demand model system proposed in 1994 by Ben-Akiva, Bowman and Gopinath.

Pre-publication draft of paper (80K PDF)


Ben-Akiva, Moshe E., and John L. Bowman (1998) Activity based travel demand model systems, in Equilibrium and Advanced Transportation Modeling, P Marcotte and S Nguyen, ed., Kluwer Academic Publishers, 20 pages.

Traces the evolution of disaggregate discrete choice travel demand models toward an activity basis.

See book on Amazon.com


Ben-Akiva, Moshe E. and John L. Bowman (1998) Integration of an activity-based model system and a residential location model, Urban Studies, 35(7), pp. 1231-1253.

Presents an integrated discrete choice model system of a household’s residential location choice and its members’ activity and travel schedules.

Pre-publication draft of paper (562K PDF)


Ben-Akiva, Moshe., John L. Bowman and Dinesh Gopinath. (1996) Travel demand model system for the information era, Transportation(23), pp. 241-266.

Proposes a comprehensive travel demand modeling framework to identify and model the urban development decisions of firms and developers and the mobility, activity and travel decisions of individuals and households.

Abstract (PDF)      Pre-publication draft of paper (not currently available)



Other publications and working papers

Castiglione, Joe, Brian Grady, John L. Bowman, Mark Bradley and Stephen Lawe (2010)  Building an Integrated Activity-Based and Dynamic Network Assignment Model, Submitted for presentation at the 3rd Transportation Research Board Conference on Innovations in Travel Modeling, May 9-12, 2010, Tempe, Arizona, USA.

Draft of paper (301K PDF)


Bowman, John L. (2009)  Historical Development of Activity Based Model Theory and Practice, Traffic Engineering and Control, Vol. 50 No. 2: 59-62 (part 1), Vol. 50 No. 7: 314-318 (part 2).

Pre-publication draft of paper (96K PDF)


Bradley, Mark, John L. Bowman and Bruce Griesenbeck (2009) Activity-Based model for a medium sized city:  Sacramento, Traffic Engineering and Control, Vol. 50 No. 2: 73-79.

Pre-publication draft of paper (56K PDF)


Bowman, John L. (2009)  Population Synthesizers, Traffic Engineering and Control, Vol. 49 No. 9: 342.

A brief note explaining population synthesizers.

Pre-publication draft of paper (11K PDF)


Bowman, John L. and Mark A. Bradley (2008) Activity-Based Models:  Approaches used to achieve integration among trips and tours throughout the day, presented at the 2008 European Transport Conference, Leeuwenhorst, The Netherlands, October, 2008.

Compares various integration techniques used by four activity-based models that have been used for travel forecasting in the US, providing conceptual understanding and reasoned discussion of their strengths and weaknesses..

Paper (PDF)      Presentation slides (PDF)      Presentation script (PDF)


Bradley, Mark.A., John L. Bowman and Bruce Griesenbeck (2007) Development and application of the SACSIM activity-based model system, presented at the 11th World Conference on Transport Research, Berkeley, California, USA, June, 2007.

A condensed version of the 2005 and 2006 ETC papers, with an additional section on application issues.

Paper (78K PDF)


Bowman, John L., Mark A. Bradley and John Gibb (2006) The Sacramento Activity-Based Travel Demand Model:  Estimation And Validation Results, presented at the European Transport Conference, September 18-20, 2006, Strasbourg, France.

A sequel to the 2005 ETC SACOG paper, this paper focuses on several aspects of the model system, including the time-of-day models, equilibration of demand and assignment, base year calibration, and sensitivity tests.

Paper (233K PDF)


Bowman, John L. and Mark A. Bradley (2006) Upward Integration of Hierarchical Activity-based Models, working paper.

Discusses the importance and difficulty of achieving upward vertical integration in activity based models, and a few techniques used by Bowman and Bradley to achieve it.

Paper (25K PDF)


Bowman, J.L. and G. Rousseau (2006) Validation of the Atlanta (ARC) Population Synthesizer (PopSyn), white paper presented at the TRB Conference on Innovations in Travel Modeling, May 21-23, 2006, Austin, Texas.

Presents the results of initial base year and backcast validation of the ARC Population Synthesizer (PopSyn). 

Paper (58K PDF)


Bradley, Mark A. and John L. Bowman (2006) A Summary of Design Features of Activity-Based Microsimulation Models for U.S. MPOs, white paper presented at the TRB Conference on Innovations in Travel Demand Modeling, May 21-23, 2006, Austin, Texas.

This short paper provides a concise summary of important design features of various activity-based model systems that had been implemented or  recently designed as of May, 2006, for planning agencies in the U.S. The models described are those for Portland, San Francisco, New York, Columbus, Atlanta, Sacramento, Bay Area, and Denver.

Paper (43K PDF)


Bowman, John L. and Mark A. Bradley (2005) Disaggregate treatment of purpose, time of day and location in an activity-based regional travel forecasting model, European Transport Conference, October 2005, Strasbourg, France.

Presents model system design, data, and partial estimation results of the activity based regional travel forecasting model system for the Sacramento (California) Area Council of Governments (SACOG), as it stood while under development in September, 2005.  Emphasis is placed on the techniques employed for effectively disaggregating the treatment of purpose, time and space.

Paper (90K PDF)


Bowman, John L. (2004) A comparison of population synthesizers used in microsimulation models of activity and travel demand, working paper.

Microsimulation models that forecast the activities and travel of urban populations create synthetic populations and then use them to simulate the behavior of the households and persons in that synthetic population.  The features of eight population synthesizers are compared, and suggestions are made for incorporating the best features into future population synthesizers.

Paper (200K PDF)


Vovsha, Peter, Mark A. Bradley and John L. Bowman (2004) Activity-based travel forecasting models in the United States:  Progress since 1995 and Prospects for the Future , presentation at the EIRASS Conference on Progress in Activity-Based Analysis, May 28-31, 2004, Vaeshartelt Castle, Maastricht, The Netherlands.

Describes activity-based travel forecasting model systems implemented or under development in Portland, San Francisco, New York, Columbus and Atlanta, explaining attempts to incorporate behavioral realism, discussing issues that interfere with their acceptance in practice, and suggesting a research agenda relevant to implementation of practical activity-based models.

Paper (100K PDF)


Bowman, John L. (2003) Logit kernel (or mixed logit) models for large multidimensional choice problems:  identification and estimation, presented at the European Transport Conference, October 3-5, 2005, Strasbourg, France, 2005, and at Transportation Research Board Annual Meeting, Washington, D.C., January, 2004.

Presents an identification rule and insights for estimation of the class of error component logit kernel models.  These are logit kernel (or mixed logit) models involving heteroscedasticity and subsets of alternatives with shared unobserved attributes.  A case study demonstrates the specification, identification and estimation of the type of model for which EC is useful—one with large choice set and a choice outcome consisting of two or more variables considered simultaneously.

Paper (884K PDF)


Bowman, John L., Dinesh Gopinath and Moshe Ben-Akiva (2002) Estimating the probability distribution of a travel demand forecast, working paper.

Presents a practical method for estimating the probability distribution of a travel demand forecast.  Given a forecast of any variable of interest, such as revenue or ridership, the approach identifies independent sources of uncertainty, estimates a probability distribution of each source, estimates the sensitivity of the variable to each source, and then combines the effects.  A case study is presented in which the probability distribution of a revenue forecast is developed for a new transit system.

Paper (161K PDF)


Bradley, Mark A. , John L. Bowman and T. Keith Lawton (1999) A Comparison of Sample Enumeration and Stochastic Microsimulation for Application of Tour-Based and Activity-Based Travel Demand Models, European Transport Conference, September 1999, Cambridge, UK.

Paper (57K PDF)


Bowman, John L., and Moshe E. Ben-Akiva (1999) Incorporating Activity Utility, At-home Activities and Lifestyle in an Activity-based Travel Demand Model, working paper.

A shortened version of Bowman's Ph.D. dissertation (see above).

Paper (100K PDF)


Bowman, John L., and Moshe E. Ben-Akiva (1997) Activity based travel forecasting, in Activity-Based Travel Forecasting Conference, June 2-5, 1996:  Summary, Recommendations and Compendium of Papers, New Orleans, Louisiana. USDOT report #DOT-T-97-17, 32 pages.

An examination of the theory underlying activity based travel forecasting models, and the classification of the differences among modeling approaches, provide a framework that is used to compare six important examples.

Paper (118K PDF)


Presentations

Bowman, John L. (2009)  Activity Model Development Experiences, TMIP Webinar, June 18, 2009.

This presentation is for those who are considering a move to activity-based models.  It describes an activity-based model, starting from the familiar trip-based model framework.  Then it explains the basic development approaches, tasks and roles; mentions keys to success; and offers suggestions for proceeding.

Presentation slides (1466K PDF)    Presentation script (48K PDF)


Bowman, John L. (2009)  Activity-Based Models:  1994-2009, presented at the MIT ITS Lab, Cambridge, Massachusetts, March 10, 2009.

Presentation slides (1318K PDF)    Presentation script (29K PDF)


Bowman, John L. (2008)  How is an Activity-Based Model Set Developed? presented at the Chicago Metropolitan Agency for Planning Symposium on Developing and Implementing an Activity-Based Travel Demand Model, August 27, 2008.

A pre-cursor of the TMIP webinar on activity model development (see above).

Presentation slides (1458K PDF)    Presentation script (56K PDF)


Bowman, John L. (2008)  The Day Activity Schedule Approach of Bowman, Ben-Akiva and Bradley:  1994-2008, presented at the Transportation Research Board Innovations in Travel Modeling Conference, June 22-24, 2008.

Traces the development of the day activity schedule approach from its birth at MIT in 1994 through its real-world implementations as of 2008.  Includes slides from early presentations.  Emphasizes the original concepts and findings, as well as enhancements that have occurred since then.

Presentation slides (940K PDF)    Presentation script (26K PDF)


Bowman, John L. (2008)  From Theory To Practice:  What can we learn from our U.S. experience? presented at the Transportation Research Board Annual Meeting Task Force on Moving Activity-based Approaches into Practice, January 13, 2008.

A retrospective examination of the activity-based model development projects sponsored by regional planning agencies in the United States.  The presentation takes a project by project look at the innovations that occurred, then considers why some projects were more successful than others.

Presentation slides (331K PDF)    Presentation script (14K PDF)


Project Documents


Sacramento

SACSIM is a regional travel forecasting model system, developed in 2005 and implemented in 2006 for the Sacramento (California) Area Council of Governments (SACOG).  The system features an integrated econometric microsimulation of personal activities and travel (DAYSIM) with a highly disaggregate treatment of the purpose, time of day and location dimensions of the modeled outcomes.  Here are various technical documents produced during the development and implementation of SacSim and DaySim.  They provide a very detailed description of the model system.  However, they are historical documents and may differ in some cases from the model’s initial or current implementation.

Package of all the following documents (3000K Zip file)

Design and planning documents (pdf files)
Preliminary design report (2002)
Addendum (2003)
Technical memo 1—Model System Design (early 2005) The best design overview of DaySim
Phase 2 Working Paper 2.1 (June 2005)

Models (pdf files)
Technical memo 2—Population Synthesizer
Technical memo 4—Mode Choice
Technical memo 5—Intermediate Stop Location
Technical memo 6—Day Pattern Activity Generation
Technical memo 7—Time of Day/Activity Scheduling
Technical memo 8—Usual and Tour Destination
Technical memo 9—Household Auto Availability
Technical memo 11—Impedance and Accessibility Effects

DaySim program (pdf files)
Technical memo 3—Design of Model System Application Software
Technical memo 10—DaySim05 Documentation

SacSim (pdf files)
Application of an Activity-Based Travel Model of the Sacramento Region (SacSim) September 21, 2006 draft
Sacramento Activity-Based Travel Simulation Model (SACSIM07): Model Reference Report November 2008 review draft
Report of the SacSim Improvement Program Peer Review Panel November 2008

Papers (pdf files)
Bowman, John L. and Mark A. Bradley (2005) Disaggregate treatment of purpose, time of day and location in an activity-based regional travel forecasting model, European Transport Conference, October 2005, Strasbourg, France.
Bowman, John L., Mark A. Bradley and John Gibb (2006) The Sacramento activity-based travel demand model:  estimation and validation results, European Transport Conference, September 2006, Strasbourg, France.
Bradley, Mark, John L. Bowman and Bruce Griesenbeck (2010) SACSIM: An applied activity-based model system with fine-level spatial and temporal resolution, Journal of Choice Modeling (publication pending)


Seattle

Puget Sound Regional Council (PSRC) is implementing an activity-based travel demand model system, using an enhanced version of DAYSIM.  When completed, it will be integrated with the PSRC UrbanSim land use model within the OPUS software environment.  While the new model system was being designed, a preliminary version consisting of an activity generator was integrated with the existing four-step model.  This hybrid model system is being used while the full AB model system is under development.  Here are technical documents that have been produced during this project
.
Activity generator estimation, calibration and user guide (2008)
Activity Model Work Plan & Activity Generation Model:  Work Plan Report (2008)
Development and Implementation of an Activity-Based Transport Model System: Report 1: Design Issues and Their Resolution (2009)


Planning studies for advanced model development

Planning and design studies have been conducted for the Southern California Association of Governments (SCAG) and for the Tampa Bay region of Florida.  Here are the reports from those studies.

Tampa Bay region (2008)
SCAG (2009)


Software
The discrete response models in the above papers and projects were all estimated with ALOGIT software.  ALOGIT can be used to estimate very large MNL and nested logit models required in practical transportation and other choice model applications.  The latest version, ALOGIT 4, can use simulation methods to estimate logit models with random parameters (ie, mixed logit, error-components logit, logit kernel).  For information about ALOGIT see http://www.alogit.com.  For information about potential discounts, email John_L_Bowman@alum.mit.edu.