Applications for GIS Week 1: Crime Analysis

     This week I learned about how GIS is used for crime analysis to help law enforcement. The module was focused on three different methods used to identify crime hotspots. These methods are grid overlay, kernel density, and local Moran's I. The maps below display hotspots for homicides committed in Chicago in 2017 and show the difference of the results of each method. The grid-based overlay uses aggregated data to determine the hotspots. The kernel density map uses point data and weighs points closer to a search areas center more heavily than those on the edge, creating a smoother data result. This was achieved in ArcGIS Pro by using the kernel density tool. The local Moran's I method uses aggregated data to group clusters of high occurring and low occurring instances, as well as outliers such as a high occurrence surrounded by low occurrences, or vice-versa. These maps were achieved by using a spatial join to combine the homicide statistics with census data and find the density of the crimes by dividing by the number of households in the area.

    The Local Moran’s I map covered the most area and is useful for identifying clusters as well as statistically significant outliers within the data. The grid overlay method provided very precise results showing only the areas with the highest concentration of homicides. I believe the kernel density method is the most useful as it shows more precise clusters due to the kernel smoothing and weighted data to identify patterns of crime.

Comments

Post a Comment

Popular posts from this blog

GIS Programming Week 3

Image
       This week I learned the basics of fixing errors within your Python script, a process called debugging. I was provided with a few scripts that contained several errors, and it was up to me to address the issues and make the script functional.  To find the problems in the code to debug them, I first ran the script to see what errors occurred. The error messages in the Python Shell were quite helpful as they told me what type of error it was, as well as the specific line it came from. Most of the troubles were simple spelling or syntax errors, which were easy to fix and help further familiarize me with the proper grammar of Python. I found the entire process quite enjoyable and rewarding. Below is the final output of the first two scripts I fixed, which retrieved shapefile information from a project in ArcGIS pro.      For the final script, I was told to not fix any errors found, but to instead employ a "try/except block", a tool used to work ...
Read more

Cartography Week 5: Choropleth and Proportional Symbol Mapping

Image
  This week I created a choropleth map based on the principles I've learned. A choropleth map is a thematic map that uses color mapping symbology to represent data. You have likely seen one of these in the form of an election map. The choropleth map above uses proportional symbolling, symbols that scale with the data, to depict wine consumption in Europe in 2012 compared to the population density in each country.
Read more

GIS Programming Week 5

Image
This week I learned about manipulating spatial data within Python. I used what I learned to create a script that creates a new geodatabase, copies shapefile data to that new database, and creates a Search Cursor and dictionary to isolate and print County Seat cities in New Mexico and their respective population circa 2000. I found the first few steps of the lab straightforward, but first ran into trouble when creating the Search Cursor. At first, the output printed on the same line and looked very messy. To fix this, I ended each line by inserting an escape character <\n> to the script, which fixed that issue. I had the most trouble populating the empty dictionary. The output initially only gave me the last key in the dictionary, but I realized this was because the line of code creating the empty dictionary was blocking the for loop, so I moved it up a few lines and was able retrieve the whole dictionary successfully. I also ran into trouble while trying to place all of my print ...
Read more