Crime in Chicago
Density of crime in Chicago for 2017 and 2018.
I used the City of Chicago's "Crimes - 2001 to Present" dataset, which has location data for reported crimes. My idea was to show crime in the city, year over year.
Here's a sketch of my initial graphic spec:
DATA: Chicago Public Data "Crimes - 2001 to Present" COORD: rectangular on dimensions 1 and 2, facet by year ELEMENT: binned hexagons at (Longitude, Latitude), hue by density of data GUIDE: Legend for interpreting binned hexagon hue GUIDE: Title "Crimes in Chicago (Year over Year) 2001 to Present" GUIDE: Label each facet by year
I learned that ggplot doesn't handle a ton of data that well.
The crime is very concentrated near the Loop, so I zoomed in by restricting the graphic
g to see if there were better details (see zoomed figure).
g + xlim(-87.65, -87.6) + ylim(41.87, 41.9)
The amount of crime in the Loop overwhelms the rest of the map. My instinct is that this makes the graphic bad because it means we can't really get a sense of crime elsewhere in the city, but I also think that it does a great job illustrating how much crime takes place in the Loop.
Another thing I noticed with the graphic is that there are holes in the coverage. But those are distracting, so how should I deal with that? Thoughts:
- I could impute the values from surrounding cells.
- The default background color could be made to be the same as the fill scale bottom color?
I also wonder if there is a good way to get "year minus year" values in a hexagon grid.
Code used to create "Crime in Chicago"
- code.r - A fragment of the code used to produce the graphic (lost the original code).