RESULTS
Part I: Environmental Justice and Socio-Economic Variables
Figure 2: Black population ratio
Figure 3: Hispanic or Latino population ratio
Figure 1: Distribution of White population
Figure 4: Asian population ratio
Figure 5: Other race population ratio
Race and Ethnicity
Choropleth maps show the distribution of White population and the ratios of Black, Hispanic or Latino, Asian, and other race to the White population in Chicago in 2015. We used population ratios to map the degree of balance between White population and other races because the ratio is normalized to refer to a standard unit of people. The community area with black color is a community with all Black population. Further, darker colors indicate there are less White people in that community area compared to other races (Figure 2-5). Triangle features are the locations of reported toxics release facilities in Chicago; moreover, the colors show the total amount of toxins released at each facility. Red color means there are high pollution emissions; whereas, blue color reveals low emissions.
The purpose of these maps is to examine the spatial distribution of visible minorities and determine if they are clustered around polluted facilities. Firstly, the White population is concentrated in far north and far southwest sides (Figure 1). Black people and other races are aggregated in the southeast side, where there are fewer facilities (Figure 2; Figure 5). The Hispanic or Latino population is clustered in Humboldt Park, South Lawndale, and the southwest side, where there are high concentrations of facilities, especially there are three facilities with high emissions (Figure 3). Lastly, Asian people mostly live in the middle part of Chicago, where there is also high clustering of facilities (Figure 4).
Income
Figure 6: Median Household Income
Figure 6 displays the distribution of median household income and its relation to the locations of toxics release facilities. Areas with darker green colors reveal higher household income where the lighter color is the opposite. The map shows that the north and southwest sides have higher income compared to other regions; moreover, the White population is concentrated in these areas (Figure 1 & Figure 6). Higher median income areas have fewer toxins release facilities, except New City. New City is a diverse community area where ethnicity groups are evenly distributed. Conversely, toxins release facilities are located and clustered in areas with lower median income.
Exploratory Regression
The exploratory regression tool helps to analyze the relationship between crime incidents and a set of socio-economic variables. The result shows that age is not a significant factor in explaining criminal activities. For instance, age only explains around 5 percent of each type of criminal activity. On the other hand, race and income could be critical factors in influencing crime incidents. For example, the percentage of Black people and unemployment rates are significant explanatory variables for each type of crimes. The Black population and unemployment rates respectively explain 24 percent and 22 percent of assault incidents, 28 percent and 25 percent of battery incidents, 18 percent and 11 percent of burglary and robbery, and 23 percent and 22 percent of offenses in Chicago.
Part II: Environmental Justice and Crime
Figure 7: Kernel Density
Kernel Density
Figure 7 shows the density of total amount of toxic released by facilities in Chicago. Facilities with high amounts of pollutant emission are concentrated in Central, West Side, and South Side. In particular, community areas like Near West Side Lower West Side, South Lawndale, New City, Garfield Ridge, and South Deering has the highest concentration. Ford Motor Co. Chicago Assembly located in South Deering community area is an outlier that its annual emission is way greater than all other facilities.
Comparing Indoor and Outdoor Assault
Figure 8: Comparing indoor and outdoor assault
Indoor assault is clustered in West Englewood, Englewood and Auburn Gresham in Southwest Side of Chicago (Figure 8). These community areas tend to have low toxic releases. West Garfield Park, East Garfield Park, and North Lawndale have moderate assault rate and moderate toxic emissions. In the case of outdoor assault, the frequency of assault crime is significantly decreased in Englewood area but increased in Garfield area. However, both of maps do not show a positive relationship between assault frequency and toxic releasing density because the highest frequency of assault is not found in highly degraded neighborhoods. On the contrary, the assault frequency is quite low in these areas. We also fail to observe an increase in crime frequency when the location of assault incidents is changed from indoor to outdoor.
Figure 9: Comparing indoor and outdoor battery
Comparing Indoor and Outdoor Battery
Indoor battery activities are clustered in Southern Chicago region (Figure 9). In particular, community areas like West Englewood, Englewood, Roseland, West Pullman, and South Chicago, have the highest frequency of indoor battery. North Lawndale has a moderate frequency of battery. High frequency of battery incidents is located in relatively low toxic releasing communities.
Comparing outdoor battery frequency with indoor battery frequency, we can see a significant increase of crime in West Garfield Park, East Garfield Park, and North Lawndale region as well as Loop and Near South in Central Chicago. However, the frequency of battery is decreased in Southern Chicago. Garfield-Lawndale region and Central Chicago are communities with relatively high toxic releases. Both indoor and outdoor battery frequencies for Near West Side, New City, and South Deering, where the highest pollution is found, are very low.
Comparing Indoor and Outdoor Burglary & Robbery
Figure 10: Comparing indoor and outdoor burglary & robbery
The frequency of indoor burglary & robbery is relatively low compared to other types of crime (Figure 10). It is mainly concentrated in Englewood, South Chicago, and Roseland, where the amount of toxic released is low. On the other hand, outdoor burglary & robbery is clustered in Astin, Garfield Park, North Lawndale, Near North, Loop, Near South, and South Shore. The overall frequency of burglary and robbery in Southern Chicago is decreased when the location is shifted from indoor to outdoor.
Figure 11: Comparing indoor and outdoor offense
Comparing Indoor and Outdoor Offense
Both indoor and outdoor offense tend to cluster in Austin, Garfield, Englewood, and South Shore. These communities are areas with relatively low toxic releases. The frequency of offense significantly decreased when the location is shifted from indoor to outdoor. Moreover, the crime frequency is not increased in high toxic release neighborhoods when the location is changed to outdoor. High polluting neighborhoods like Near West Side, Lower West Side, South Lawndale, New City, and South Deering have low crime frequency for both indoor and outdoor offense.