This project uses Caltrans PeMS data to evaluate traffic conditions on I-15 in San Diego County, with a focus on comparing managed/express lane performance with nearby general purpose lanes.
The analysis:
- Reads and cleans District 11 PeMS station-hour data.
- Identifies healthy stations based on data completeness.
- Matches managed lane stations with nearby general purpose lane stations.
- Compares speeds and traffic volumes by direction and time of day.
- Produces tables and maps for reporting.
Creates the master PeMS dataset used for the analysis.
The script:
- Reads monthly PeMS station-hour files.
- Reads PeMS station metadata.
- Filters to I-15 northbound and southbound stations.
- Adds station location information.
- Creates data-quality flags.
- Saves the cleaned master dataset.
Performs the main analysis.
The script:
- Evaluates station health.
- Selects usable managed lane and general purpose stations.
- Matches managed lane stations to nearby general purpose stations.
- Calculates speed and volume measures.
- Produces comparison tables and maps.
Working documentation describing the methodology, assumptions, and results.
Raw PeMS data are not stored in this repository because of file size.
The project expects source data to be stored locally in:
1_Source Data/PeMS Station Data/
PeMS station metadata should be stored under:
1_Source Data/
The analysis uses packages including:
- tidyverse
- janitor
- lubridate
- writexl
- sf
- ggplot2
- ggrepel
Work in progress.