ILGA District Crashes Analysis

Analysis of traffic crashes in Illinois General Assembly districts within Chicago, including specific analyses of high-crash corridors.

Data Sources

• Traffic Crashes Data: City of Chicago Data Portal
• Traffic Fatalities Data: Vision Zero Chicago Traffic Fatalities
• Illinois House Districts Shapefiles
• Illinois Senate Districts Shapefiles
• Chicago Ward Boundaries

Repository Structure

ilga_district_crashes/
├── data/
│   ├── raw/              # Original data files
│   │   ├── shapefiles/   # Geographic boundary files
│   │   │   ├── house/    # House district shapefiles
│   │   │   ├── senate/   # Senate district shapefiles
│   │   │   └── wards/    # Ward boundary files
│   │   └── crashes/      # Original crash data
│   └── processed/        # Processed data files
├── R/                    # Analysis scripts
├── output/              # Generated files
│   ├── maps/            # Generated maps
│   └── summaries/       # Summary CSV files
└── README.md

Analysis Scripts

• utils.R: Shared functions and constants
• city_crashes.R: Citywide crash analysis
• lakeshore_crashes.R: Lake Shore Drive corridor analysis
• archer_crashes.R: Archer Avenue corridor analysis
• pulaski_crashes.R: Pulaski Road corridor analysis
• lasalle_crashes.R: LaSalle ramp analysis

Setup

1. Download the traffic crashes dataset from the City of Chicago Data Portal
2. Download the fatality data from the Vision Zero Chicago Traffic Fatalities dataset
   • Required fields for fatality data:
     • person_id
     • crash_date
     • crash_location
     • victim
     • crash_circumstances
     • longitude
     • latitude
   • Export as CSV using the "Export" button in the top right
3. Place both downloaded CSVs in data/raw/crashes/
4. Place district shapefiles in appropriate directories:
   • House district files in data/raw/shapefiles/house/
   • Senate district files in data/raw/shapefiles/senate/
   • Ward files in data/raw/shapefiles/wards/
5. Install required R packages:

   install.packages(c(
     "dplyr", "readr", "purrr", "geosphere", "ggplot2",
     "ggmap", "magrittr", "leaflet", "sf", "osmdata",
     "leaflet.extras", "lubridate", "tidyr", "knitr"
   ))

Running the Analysis

Each script can be run independently to analyze different aspects of the crash data:

1. Run utils.R first to load shared functions
2. Run any of the analysis scripts:
   • city_crashes.R for citywide analysis
   • lakeshore_crashes.R for Lake Shore Drive analysis
   • archer_crashes.R for Archer Avenue analysis
   • pulaski_crashes.R for Pulaski Road analysis
   • lasalle_crashes.R for LaSalle ramp analysis

Outputs

• Summary CSVs in output/summaries/
  • District-level summaries
  • Corridor-specific analyses
  • Crash statistics and economic impact estimates
• Interactive maps in output/maps/
  • Fatality visualizations
  • Crash density heatmaps
  • District-level analysis maps

Data Processing Notes

• Date range: 2019-01-01 to 2023-12-31
• Economic damage estimates based on NSC injury cost estimates
• Spatial analysis uses 750ft buffers for corridor analysis
• All spatial data is transformed to EPSG:4326 for consistency

Required Data Fields

The traffic crashes CSV should contain the following key fields:

• CRASH_RECORD_ID
• CRASH_DATE
• LONGITUDE
• LATITUDE
• INJURIES_TOTAL
• INJURIES_INCAPACITATING
• FIRST_CRASH_TYPE
• HIT_AND_RUN_I

License

This project is open source and available under the MIT License.