Change for the better

CHANGE FOR THE BETTER? An Analysis of Crime Surrounding Demolished CHA Buildings

By: Christopher Quy-Hac Tran

UPP 461.WED 6PM

Introduction Prior to the WWII era, Chicago faced a housing crisis, where many lower-income residents were living in slum tenements throughout the city’s many neighborhoods. Between the mid-1950s until the late 1960s, the Chicago Housing Authority introduced a new housing policy sought to combat such housing form, as there was an emergence of high-rise apartment complexes, which moved lower income, predominantly black residents living in the slum tenements to these towers.

Cabrini Green, and the Robert Taylor homes in Chicago, two of the more iconic public housing buildings in Chicago, in its early stages, offered safer, higher quality housing for poor Chicagoans.

Throughout the 30-40 years of this type of housing, disinvestment and lack of CHA support & management, and the increase in crime, gang violence, and drug trafficking plagued public housing, which eventually led to its demise.

During the late 1990s, early 2000s, the CHA embraced a new policy, “The Plan for Transformation” which focused on more mixed-income housing as opposed to high-rise structures. As a result, many of the former buildings were demolished as crime and vice were seen as key provokers in the shift of policy. Thus, one of the key rationales for the shift from high-rise to low-rise, mixed income was due to density of crime.

As we approach over ten years from the Plan for Transformation, and as CHA embraces a new housing policy, it is important to review and analyze particular policy decisions of the past and see if in fact they were effective.

Project Description For this project, I would like to use Geographic Information Systems (GIS) as a tool to analyze crime from 2001, 2006, and 2011; the time frame of demolition of many of the CHA buildings to see whether or not there is a correlation between decrease in crime and demolition of CHA buildings. As previously stated, one of the main reasons for shift in housing policy was crime.

I hypothesize that the demolition of former CHA Public Housing Buildings have not significantly decreased crime rates that defined the public policy decision of shifting from high-rise to mixed-income.

I hope to prove this through data collected through various sources, and using ArcMap 10.1 to map crimes around demolished CHA buildings.

Data The first step of the project was compiling data for analysis. For the crime data, I went to the City of Chicago Data Portal website (https://data.cityofchicago.org/) and searched for crime data from 2001, 2006, and 2011. I then exported these tables as excel files.

As for the CHA buildings, I looked at Wikipedia (Yes, sometimes not a great source for data) to find a list of CHA buildings that were demolished. Furthermore, there is an existing Google Maps document

online, which lists the coordinates (longitude, latitude) for current existing, and demolished high-rise buildings throughout the City of Chicago. I compared the list I compiled from Wikipedia to this list to see which ones were still missing coordinates. For the buildings that were missing, I searched on Wikimapia, which provided the coordinates the buildings I needed for this project. (See Bibliography for details) Difficulties There were several road blocks that I encountered throughout the process of this project. Prior to searching for data, I assumed that finding the exact addresses of the demolished CHA buildings would be no challenge. Throughout researching online, I was unable to find exact addresses for these buildings, so I had to find a different route in being able to plot these as a shape file. Through the online tutorial provided by the course instructor for plotting XY (Longitude, Latitude) coordinates, I figured that I should find the X, Y coordinates of these buildings. This was not much of a challenge as I was able to obtain them through the Chicago Housing Authority Project Map (Google Map document), and through Wikimapia.

Some other minor difficulties I faced were through the projection of these coordinates, which were documented as an excel file. Throughout our course, we used the NAD_1983 Geographic Coordinate System (GCS) as the default, but there were problems projecting the points in this GCS. I had to find an alternative, which I did, through the WGS 1984 GCS. I was interested in finding alternatives to visualize change in density of crime surrounding the demolished CHA buildings beyond just dots on a map, so I had to learn a new tool. I was able to quickly learn a Spatial Analyst Tool, called Point Density to be able to create various density maps that allowed for better visualization of the data, which can be seen in the appendix of this report. Though this process was not truly a difficulty, learning a new tool within ArcGIS can be considered a challenge.

General Tools Used The following are a list of ArcGIS tools used for the analysis of this project. They are as follows: Adding XY Data, Projection, Buffer, Select by Location, Summarize, Select by Attribute, Point Density Spatial Analyst Tool, Symbology, and Classify. Furthermore, I also used Calculate by Geometry to figure out the total square feet of Chicago, as well as the buffer created for this analysis.

Process and Spatial Analysis I first started the project by collecting crime data from the City of Chicago Data Portal, and exported it as an excel file for the years 2001, 2006, and 2011. Within these excel files, there was an abundance of unneeded information, so I copied and pasted just the types of crime, as well as the longitude and latitude points in all three excel files. As previously mentioned, I documented the longitude and latitude points for the demolished CHA buildings and also created an excel file.

Before adding the excel files to my data, I wanted to have a reference of Chicago, so I added the chicagoblod.shp file to my workspace on ArcGIS 10.1. Following this, I added the excel files through tools, Add Data, Add XY Data. I projected all of these files (Crime 2001, 2006, 2011 and the CHA demolished buildings) in WGS1984 GCS. For all of these, I had to go into project, and use NAD1983 as the GCS to get the correct project of all the crimes and demolished CHA buildings.

Visually, I was able to see how the crimes changed every five years between 2001 and 2011, but what I wanted to analyze was crime around the former CHA buildings (14 buildings to be exact) that have thus been demolished. From 2001 to 2011, through analysis of the attribute tables, I was able to see that crimes continued to decrease throughout the entire city every 5 years. Appendix 3 shows the table of the crimes from these three years.

What I was interested in though was crime around a half-mile radius of these buildings. In order to do so, I had to create a buffer around these points, which I used through the Geoprocessing tools. By building a half mile buffer around these buildings, I was able to see which types of crimes intersected this buffer on the map. Appendix 1 shows two images, one of the demolished CHA buildings, and one with the buildings with a half-mile buffer.

Zooming in, and counting every single dot that represented a crime from 2001, 2006, and 2011 would be too much of a strain, so I decided to use Select by Location in order to see which crimes intersected the half-mile buffer. (See Appendix 2 for SBL Intersection Maps) Through this process, I was able to analyze exactly how many total crimes throughout the city in 2001, 2006, and 2011 intersected the half-mile buffer. I opened the attribute tables for each year to document the numbers.

(See Appendix 3) Through this analysis, I was able to see the actual numbers decreased in crime throughout the entire city of Chicago, as well as numbers of crimes decreased within the half-mile buffer. As crime has consistently decreased throughout the entire city, I wanted to see if the percentage of decreased crime was higher or lower within the buffer areas. For crimes throughout the entire city, there was a decrease of 253 crimes from 2001 to 2006, which is a 1% change. From 2006 to 2011, there was a decrease in 448 crimes, which equates to a 30% change. Comparing these numbers to the crimes from all three years, we see a decrease of 299 or 25% from 2001 to 2006. From 2006 to 2011, we see a decrease of 251 or 40% in crime. In comparison, it seems like throughout the beginning stages of demolition of CHA buildings, the crime rate fell at a higher rate than throughout the entire city as a whole.

I wanted to take it a step further and analyze the top three crimes throughout Chicago. In order to do this, I summarized the shape files for crime from 2001, 2006, and 2011 to see which crimes were most frequent. Through summarizing the 2001 data, it appeared that the top three most frequent crimes were Battery, Narcotics and Theft. I used this as a baseline for the other years for comparison.

To visualize only these three crimes on the map, I used the Select by Attribute tool and used the following function: “Type” IN (‘THEFT’, ‘NARCOTICS’, ‘BATTERY’) to select these specific crimes for 2001, 2006, and 2011. I then created a shape file out of these selected attributes to cut down the

data. I then analyzed the data from the attribute table to figure out the total crimes within these three types for years 2001, 2006, and 2011. These numbers are shown in Appendix 3.The relevant data though were the crimes that were within the half-mile buffer of demolished CHA buildings. For this data, like all crimes data from all three years, I then used the Select by Location tool to see which of these crimes intersected the buffer. The maps from all three years which show only the crimes within the buffer can be seen in Appendix 4.

Through the attribute tables, I summarized the data for the 3 types of crime for all of Chicago in all three years, as well as 3 types of crime within the buffer for all 3 years as well. This table can be seen in Appendix 3. From 2001 to 2006, there was a decrease in 223 crimes or a change of 3%. From 2006 to 2011, there was a decrease in 88 crimes, or a 1% change. Compared to these number, I looked at the changed in crime density within the buffer. From 2001 to 2006, there was a decrease in the 3 types of crime of 236 or 35% decrease. From 2006 to 2011, there was a decrease of 102 crimes in the 3 categories, or a 24% change. Through this analysis, we can see that the decrease in the top 3 highest crime categories are much higher within the half-mile buffer of CHA buildings than throughout the entire city of Chicago.

The final visual analysis I attempted for this project was the point density analysis through the Spatial Analyst toolbox. I wanted to visualize the density changes from 2001, 2006, to 2011 of both All Crimes and 3 Types of Crimes. I inputted the shape files into the point density tool box that popped up, and changed various settings (see Project Log for Details), changed the symbology as well as the classification settings to create 2 sets of maps for all three years. Appendix 5 shows these maps.

Upon further suggestion of the instructor, I sought out to document the crimes per square mile within Chicago for all crimes from 2001 to 2006 to 2011, as well as 3 types of crime from the same time period to analyze density through a different method. From my findings, I was able to compare the crimes per square mile of all crimes throughout Chicago with the crimes per square mile within the halfmile buffer. Furthermore, I was also able to analyze crimes (3 types) per square mile for all throughout the entire city with those committed within the buffer. Through both of these analyses, the crimes committed per square (for both All Crimes and 3 types of Crimes) were much more dense within the half-mile buffer as opposed to all throughout the entire city. For further information, please refer to Appendix 6 for detailed tables showing exact numbers.

Conclusion Through all these different levels of analysis, my original hypothesis of crime not decreasing around demolished CHA buildings throughout the years has been proven false. Through all of these types of mapping and spatial analyses, through documenting percentage changes in crime surrounding the buffer vis-Ă -vis the entire city, as well as crimes per square mile, there has been consistent documentation that crime has decreased within a half-mile buffer of demolished CHA buildings.

Through this analysis, one could say that the rationale for CHA high-rise demolition and a shift from this housing policy to that of mixed-income was a legitimate policy shift.

Using GIS was vital to this analysis because it allowed me to map and analyze data that otherwise couldn’t have been done. Building a buffer, and calculating number of crimes per square miles, and being able to visualize it through the tools of maps cannot be done through only excel. What can possibly be done to expand and create a more in-depth analysis would be to analyze former CHA buildings that may have not been demolished but renovated and compare the statistics. Ultimately, this project is just a start to a further, more developed analysis.

Appendix 1

Appendix 2

Appendix 2 Continued

Appendix 3

Change in All Crimes in Chicago Surrounding Demolished CHA High-Rise Buildings, 2001, 2006, and 2011 2001

2006

2011

Total Crimes in Chicago

13,821

13,568

13,120

Total Crimes w/in half-mile Buffer of CHA High-Rise Buildings

1,174

875

624

Appendix 4

Appendix 4

Continued

Appendix 5

Appendix 6

All Crimes per Square Mile in Chicago and 1/2 Mile Buffer of Demolished CHA Buildings (2001, 2006, and 2011) 2001

2006

2011

Chicago

59.85

58.75

56.81

1/2 Mile Buffer

134.04

99.90

71.24

Crimes (3 Types) per Square Mile in Chicago and 1/2 Mile Buffer of Demolished CHA Buildings (2001, 2006, and 2011) 2001

2006

2011

Chicago

29.34

28.37

27.99

1/2 Mile Buffer

75.47

48.52

36.88

Bibliography City of Chicago Data Portal. https://data.cityofchicago.org/. Download Date 2013 November 15.

Downloaded Crime Data from 2001, 2006, and 2011.

Wikipedia, Chicago Housing Authority. http://en.wikipedia.org/wiki/Chicago_Housing_Authority.

Download Date 2013 November 15. Documented Demolished CHA Buildings Chicago Housing Authority Project Map. https://maps.google.com/maps/ms?msa=0&msid=204367138976189903546.0004da8f88 79fb298e8bb. Download Date 2013 November 15. Documented Longitude, Latitude Data of CHA Buildings.

Wikimapia. www.wikimapia.org Download Date 2013 November 15. Downloaded Longitude, Latitude of CHA Buildings.