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Frequently Asked Questions

Data questions

Where does the data come from?

The data comes from the Illinois Department of Transportation (IDOT), Division of Traffic Safety. The reports for Chicago come from the Chicago Police Department (CPD).

Does the bike crash data include doorings?

No. This will change in 2011. 2012 will be the first full year of data where doorings are included. The CPD collects this data but prior to Governor Pat Quinn's rule change on April 25, 2011, IDOT refused to track it. The rule affects all police departments in the state.

What else does the data exclude?

The data excludes crashes when a bicyclist hit another bicyclist, a bicyclist crashed against a non-automobile object (like the ground, a bridge, a post), and when a bicyclist hit a pedestrian.

Why doesn't the Chicago bike crash data include street addresses?

Street address information is not provided in the crash data from IDOT. This is because they're not relevant. When the report comes in to IDOT, a worker there pinpoints the crash on a map based on all of the information provided in the report. Many reports come in with street addresses and these are found on the map. Many reports come without street addresses, but instead have descriptions like "100 feet west of intersection of Damen and Elston."

Does IDOT offer any indication of who was at fault in their data?

No. Additionally, the IDOT data doesn't consider the bicycle as a vehicle in its report. You will see that VEH1 is a car, and VEH2 doesn't exist. The full dataset (not the "extract" that powers these applications) includes causes, like distractions or lack of driving knowledge.

I cannot find my crash in the map. Why is this?

Did you report the bike crash to the Chicago police? All of this data originates with the Chicago Police Department (CPD).

If you did report it to CPD and you still can't find your crash report, this could be related to the way the police office recorded the data, or losing data as it gets converted from CPD to IDOT storage formats. I was able to find my own crash in 2007 by filtering the dates. I found that the IDOT case number had changed from what it said on my Illinois Traffic Crash Report (SR-1050) to something different in the dataset.

I am keeping a list of crash locations and times that are not found in the map or data. Send me your information.

How can I work on the data myself?

You can download the data as a CSV file from the Google Fusion Table where it was originally hosted or you can ask me for the IDOT contact information (I don't want to bombard them with the information and you need to get the data from them).

Map questions

What inspired you to create the map?

The Bay Citizen Bike Accident Tracker. But there were others: after seeing the B-SMART website for self-reporting bike crashes in Portland, Oregon, I wanted to create a similar website. I talked to several people, including Ben Sheldon who helped make the Boston Cyclists Union map from EMT data, and concluded that building an application where people could report their own bike crashes had too many caveats. I then saw the map for San Francisco bike crashes and how easily they created it with Google Fusion Tables. Less than 24 hours, my original map was born.

How many people have viewed the map?

From February 10, 2011, to May 3, 2011, there have been 4,610 unique page views (using Google Analytics). Derek's searchable map has received 220 unique page views since launch until May 3, 2011 (frankly it should have more because it's much better than my original map).

Other questions

Is there a support group for people involved in crashes?

Active Transportation Alliance operates a crash support hotline and support group for people involved in bicycle or pedestrian crashes. Read this Chicago Tribune story or get more information from ActiveTrans.

What should I do if I'm involved in a bike crash?

Always file a police report so that it's occurrence is noted in the public record and decision makers and advocacy groups will have good information on which to base their policy and planning. The Active Transportation Alliance has more tips.