Crimes occuring ON the 606 trail

In a previous post, I gave an overview of a project to investigate the occurrence of crimes near the 606 (Bloomingdale) trail in Chicago. Data for the investigation came from the City of Chicago Open Data Portal, and investigation into the data made me wonder whether I could list a subset of this data, namely the crimes that actually occurred ON the trail (versus just in the vicinity).

Identifying the crimes occurring on the trail itself came with it’s own set of challenges; I’m not sure it can be done perfectly due to a number of factors. That said, I think we can probably do a reasonable job.

 

The Challenges:

The location of crimes on the data portal have been adjusted for privacy. That is, the latitude and/or longitude are not exact so that individual homes can not be explicitly identified from the data. I’m not sure the algorithm used to due this (hopefully that’s the point of doing it), but merely knowing a crime occurred exactly on the trail does not mean the latitude and longitude reported will indicate so.

Another challenge we may face is that it may not be clear when a crime is “on the trail”.
Consider this citizen’s report here.  This sure sounds like a crime I would say occurred on the trail, but in fact sort of occurred at the foot of the ramp, so maybe is not and is actually not reported as such.

 

An Approximate Solution

There is a column on each crime row which indicates the location type of the crime. Crimes occurring on the trail are being reported with a value of ‘PARK PROPERTY’ in this column. Thus we can use a combination of latitude/longitude (proximity to the trail) and this indicator to narrow down our possibilities. But there are still issues , as there are a number of parks that abut the trail. Crimes in these parks may likely be caught in this sieve.

 

The Results
Let’s use our methods above and see what the results are. These are the crimes identified as occurring on the trail, from it’s opening on 6/6/15 through the 1/31/17.

Crime ON 606 trail thru 013117