Over the past few months, we have made substantial progress on our standards, the network preparation, and the Fast-Trips software itself. Paperwork has delayed some of our progress in the Travel Behavior task, but that is now behind us and we can push on. Here is a brief summary of a few of the things we have been working on.

Evolution of Standards

We have iterated some on our standards, and updated all of our tools to use them.

Network Standard

• Biggest pain is still the fares, which have changed slightly as we have worked through the various fare types in each region and realized that there were too many exceptions to our simplifications.
• The biggest changes to the standard are to decrease ambiguity.

Demand Standard

• Has remained more constant.

Network Creation

We have substantively completed the code to do the network creation process for Fast-Trips on the fly from within SoundCast and SF-CHAMP.

• Includes schedule creation from headways [ using GTFS if it is available ].
• Fares have been the most difficult component to “get right.” There are a multitude of fare rules by operator of multiple types [ zone, flat, station-to-station ], and multiple transfer policies. These were all roughly approximated in our current system and so transferring them to the new data standard requires a lot of care and thought.
• The PSRC Version has undergone small-scale testing and will be scaling to entire network this week. It utilizes the EMME API, so may be of limited use outside of EMME users.
• The SFCTA version is within their stand-alone NetworkWrangler and is slightly behind PSRC in maturity.

Demand Validation

Our initial investigation into validating the demand has been met with the [ not unexpected ] issue that the OD data we have [ on-board surveys and CHTS ] is significantly higher [ when weighted ] than the ridership data we have at screenlines. We are looking into this issue and hope to not get lost down this rabbit-hole if it isn’t going to benefit us too much in the long term since SF-CHAMP hits the screenline data fairly well.

Fast-Trips Travel Model Integration

Joe developed a white paper summarizing the various issues and potential strategies for feeding LOS information coming out of Fast-Trips back up to the travel demand models.

Joe, Elizabeth, and Lisa have been working to develop an approach that addresses these issues. The process is challenging, because SF-CHAMP and SoundCast have very different approaches to mode choice.

Software Released!

You can download and use Fast-Trips yourself! We had Bhargava [ somebody who wasn’t involved in the coding ] work through the small test scenario and make sure he could download, compile, and use it.

Instructions and code are on GitHub and will be summarized in a forthcoming blog post.