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Applications in GIS Module 1

 


Grid Overlay


Kernel Density:


Local Moran's I:




This weeks module focused on crime analysis using the grid overlay, kernel density and local Moran's methods. The grid overlay method (image one) involved layering a grid of half mile cells over the city of Chicago, isolating the cells in the top 20% of total homicides in 2017 and using that to compare it to locations of all the homicides in 2018 to determine where homicides where recurring. The kernel density method (image two) creates a density map by searching for clusters of points in an area and assigning points closer to the center of the search area higher weight values. All area total homicides numbering more than three times the average were isolated. Local Moran's I (picture three) determines whether points inside a cell are either clustered or dispersed and then determines whether or not they are statistically significant by comparing each cells value to the cells around it. All cells with high clustering and high statistical significance were isolated for analysis.

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