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ActivitySim

The mission of the ActivitySim project is to create and maintain advanced, open-source, activity-based travel behavior modeling software based on best software development practices for distribution at no charge to the public. Additional information about the software, as well as how to get started with the example is on our website. You may also be interested in our conference Presentations as well.

If you are interested in contributing to ActivitySim, please review the Contribution Review Criteria. Affiliated Packages are another avenue for contribution.

Project Progress and Road Map

ActivitySim work is done in Phases. Phases are twelve months in length and start in the summer. The project phases are below. In addition, the Future Features page keeps track of potential future features.

Phase V

Phase V starting in Fall 2019 is focused on:

• project management
• strategic development and contribution plan
• support for two zone systems
• input and output improvements
• support for modeling TNCs and for-hire vehicles
• model developer tutorial
• performance tuning
• PopulationSim integration
• model estimation mode
• support for three zone systems and transit virtual path building

See the Phase 5 Scope of Work for more information.

Phase IV

Phase IV in the second half of 2018 and early 2019 focused on:

• multi-processing (parallelization)
• shadow pricing
• verification and implementation of remaining features

See the Phase 4 Scope of Work for more information.

Phase III Amendment

The Phase III Amendment of ActivitySim development began in early 2018 and implemented:

• joint tour models
• stop level models
• sub-model pre- and post-processors for better data management

See the Phase 3 Amendment Scope of Work for more information.

Phase III

Phase III of ActivitySim development started in early 2017 and focused on:

• improving the data pipelining procedures
• stable random number generation
• inclusion of logsums
• implementation of person time window management
• at-work subtours

Some additional refactoring of the framework was also completed. See the Phase 3 Scope of Work for more information.

Multiple Zone Systems

Under a separate work program, SANDAG sponsored prototyping revisions to support multiple zone systems. See the Scope of Work and Test Results for more information.

Phase II

Phase II of platform development began in February 2016. The Phase II development focused on:

• Architecture Review and Testing, including development of a Getting Started tutorial
• Skim Handling Suitable for Large Set of Skims
• Accessibility Calculation Procedure
• Nested Logit Choice Model Engine
• Tracing Choice Results of Households and Persons
• A complete vectorized implementation of the Coordinated Daily Activity Pattern Model (CDAP)
• Additional Revisions to Phase 1 Implementation

See the Phase 2 Scope of Work for more information.

Phase I

Phase I of platform development was completed in the summer of 2015. An evaluation of the work completed in Phase 1 can be found in the Phase 1 Evaluation. The core capabilities established in Phase I of ActivitySim development include:

• Data Handling
• System Orchestration
• Model Specification and Expression Evaluation
• Implementation of an Multinomial logit model
• Partial implementation of 10 out of 29 MTC CT-RAMP sub-models