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SF Transit Accessibility Map

Latest beta release: 3.21 (May 26, 2015) This update temporarily disabled the 'best case' and 'worst case' features pending the results of a recalculation of those factors. In all versions prior to this one, the best and worst case travel times were calculated by combining the 85th (or 15th) percentile headway with the 85th (or 15th) percentile travel time for each segment of a route. Combining these times only yields a statistically correct result if they are independent (not related to each other). This was an assumption inherent in the model, and is true in some circumstances but not in others. Because of this, the previous versions of the map do not represent the 85th (or 15th) percentile trip, but instead showed something akin to the upper and lower bounds of trip travel time. I'm currently building an engine that will calculate all possible trips between each O-D pair and will yield the true 85th percentile travel time. These results will be posted in an update once completed.

Please note that average calculations will remain unchanged.

To help you through the wait, here is a visualization of the AVL bus position data that powers this map: Click here to launch the AVL data visualization

My transit accessibility map is out of alpha. The map utilizes Muni data from Q1 2014 and my intent is for it to be a reliable representation of current travel times using Muni. There are four modes available: Average, Best Case, Worst Case and a mode that compares the best case and worst case (a visual estimate of reliability). Please send feedback to me - hit the "C" above to see how to contact me!

Click here to launch the transit service coverage map

Click here to launch the accessibility map (alpha testing)

Previous betas:

3.1 (Feb 20, 2015) 3.1 was a simple set of icon changes.

3.0 (Nov 21, 2014) Version 3.0 presents a recalculation of the baseline data to address an issue with how dwell times are handled on infrequently-run routes. Best case is now represented by the 15th percentile times and worst case represented by the 85th percentile times. These changes make Muni Forward projections invalid and therefore the Forward and Improvement modes are disabled. UI is improving and data updates are still ongoing.

2.1 (Sep 20, 2014) Complete datasets available assuming user is willing to walk infinitely. Includes accessiblity to jobs calculati on! Select the button at left with the buildings on it to show how many jobs are accessible from any origin you choose via transit! Next update will includ e options to allow user to indicate whether they are willing to walk a maximum of 5 min or 10 min (available from settings menu) UI is improving and data u pdates are still ongoing.

2.0 (Sep 10, 2014) Version 2.0 is a complete overhaul. It now uses compression to save server space for more options and speed up load times. New UI: Rotating circle brings up time of day, options are available along the right side and across the top. The "Settings" button provides functionality for varying the assumptions made about walking. These modes are not available yet since they have not been calculated. UI is improving and data updates are still ongoing.

1.45 (Aug 25, 2014) UI is improving and data updates are still ongoing. New mode! "Improvements" compares pre- and post- Muni Forward scenarios.

1.4 (Aug 20, 2014) UI Improvements - New zoom function - click the red circles that show zoom level

1.3 (Aug 18, 2014) Errors in Muni Forward dataset corrected

1.2 (Aug 1, 2014) UI Improvements - Support for mousewheel and click and drag panning. Data update - Muni Forward projections calculated and inclued in new mode Click "Baseline" once to activate

1.1 (Jun 12, 2014) Added "target" mode letting you compare average and worst case for an visualization of reliability

1.0 (May 13, 2014) Presentation Version - beta

0.9 (May 12, 2014) Bug fixes: 1) Display error where sometimes when switching between datasets the old dataset still shows. 2) Removed the transit map from the mountain icon

0.82 (May 3, 2014) First functioning version (1st alpha)

Media

SFist "This Scenario-Based Transit Map Will Change Your Commute"

The Atlantic CityLab "Every City Should Have Something Like San Francisco's Mass Transit Access Map"

2014 World Symposium on Transportation and Land Use

Symposium Website

I presented my paper, "Economic Effects of the T-Third on Bayview" at the World Symposium on Transportation and Land Use in Delft, Netherlands this past June. I really enjoyed the conference and I hope to collaborate with some fellow attendees in future projects!

San Francisco Shuttle Study

http://www.facebook.com/SFshuttlestudy

The SFMTA Board recently passed legislation allowing the shuttles to use San Francisco transit stops in exchange for a nominal fee. The study I am co-authoring with colleague Mark Dreger seeks to find the true cost of providing private shuttles access to public infrastructure and hopefully start a conversation about pricing road usage in all its forms, from parking, to stopping, to driving. The first component of this cost we plan to look at is the cost of delays to Muni caused by the shuttles.

Media

Streetsblog SF "Transit Researchers Want Your Videos of Tech Shuttles at Muni Stops"

SFGate "How much time do tech buses spend blocking Muni stops? Study hopes to find out"

Tweets by @transitbear

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